ALBERT

Description: Dieser Band enthält Artikel zu 41 Themengebieten der Geophysik, veröffentlicht durch die Deutsche Geophysikalische Gesellschaft in dem Jahr 1981.

Description: Inhaltsverzeichnis: Journal of Geophysics 49 〈html〉 〈body〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0011.pdf"〉Palaeomagnetism of a Jurassic Ophiolite Series in East Elba (Italy) 〈/a〉〈br〉 (Soffel, H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0013.pdf"〉Paleomagnetic Evidence from Mesozoic Carbonate Rocks for the Rotation of Sardinia〈/a〉〈br〉 (Horner, F., Lowrie, W.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0015.pdf"〉A Geotectonic Paradox: Has the Earth Expanded? 〈/a〉〈br〉 (Schmidt, P. W., Embleton, B. J. J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0016.pdf"〉Application of Magnetotelluric and DC Electrical Resistivity Methods in the Neapolitan Geothermal Area〈/a〉〈br〉 (Hunsche, U., Rapolla, A., Musmann, G., Alfano, L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0018.pdf"〉Velocity Variations in Systems of Anisotropic Symmetry〈/a〉〈br〉 (Crampin, S., Kirkwood, S. C.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0019.pdf"〉Shear-Wave Singularities of Wave Propagation in Anisotropic Media〈/a〉〈br〉 (Crampin, S., Yedlin, M.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0020.pdf"〉Temperature Derivatives of Compressional and Shear Wave Velocities in Crustal and Mantle Rocks at 6 kbar Confining Pressure〈/a〉〈br〉 (Kern, H., Richter, A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0021.pdf"〉A Crustal Gravity Model of the Mare Serenitatis - Mare Crisium Area of the Moon〈/a〉〈br〉 (Janle, P.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0022.pdf"〉On the Origin of the Annual Wave in Hemispheric Geomagnetic Activity〈/a〉〈br〉 (Meyer, J., Damaske, D.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0023.pdf"〉On the Relation Between Magnetic Field-Aligned Electrostatic Electron Acceleration and the Resulting Auroral Energy Flux〈/a〉〈br〉 (Wilhelm, K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0024.pdf"〉Application of Different Methods for the Determination of Ionospheric Conductivities from Sounding Rocket Observations〈/a〉〈br〉 (Brüning, K., Baumjohann, W., Wilhelm, K., Stüdemann, W., Urban, A., Ott, W., Spenner, K., Schmidtke, G. L., Fischer, H. M.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0025.pdf"〉Numerical Experiments on Convection in a Chemically Layered Mantle〈/a〉〈br〉 (Christensen, U.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0026.pdf"〉〈i〉Book Reviews〈/i〉〈/a〉〈br〉 (Raikes, S. A., Engelhard, L., Pape, H., Theile, B.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0028.pdf"〉Steady State Creep of Fine Grain Granite at Partial Melting〈/a〉〈br〉 (Auer, F., Berckhemer, H., Oehlschlegel, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0029.pdf"〉Laboratory Synthesis of Aluminium-Substituted Titanomaghemites and Their Characteristic Properties〈/a〉〈br〉 (Özdemir, Ö, O’Reilly, W.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0030.pdf"〉Densities and Magnetic Susceptibilities of Precambrian Rocks of Different Metamorphic Grade〈/a〉〈br〉 (Southern Indian Shield) (Subrahmanyam, C., Verma, R. K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0031.pdf"〉Lithospheric Structure and Teleseismic 〈i〉P〈/i〉-Wave Reflection Delays Under Fennoscandia and Siberia〈/a〉〈br〉 (Stewart, Ian C. F.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0033.pdf"〉Propagation of Surface Waves in Marine Sediments〈/a〉〈br〉 (Essen, H.-H., Janle, H., Schirmer, F., Siebert, J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0035.pdf"〉Simultaneous Observation of an Intense 65 keV Field-Aligned Proton Beam and ULF-waves During a Break-up Event〈/a〉〈br〉 (Stüdemann, W., Goertz, C. K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0036.pdf"〉Observations of Field-Aligned Current Sheets Above Discrete Auroral Arcs〈/a〉〈br〉 (Wilhelm, K., Klöcker, N., Theile, B., Ott, W., Spenner, K., Grabowski, R., Wolf, H., Stüdemann, W., Dehmel, G., Fischer, H. M., Schmidtke, G. L., Baumjohann, W., Riedler, W., Urban, A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0038.pdf"〉Multi-Method Observations and Modelling of the Three-Dimensional Currents Associated with a Very Strong Ps6 Event〈/a〉〈br〉 (Gustafsson, G., Baumjohann, W., Iversen, I.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0040.pdf"〉Variability of Solar EUV Fluxes and Exospheric Temperatures〈/a〉〈br〉 (Schmidtke, G., Börsken, N., Sünder, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0041.pdf"〉Paleomagnetism of Quaternary and Miocene Lavas from North-East and Central Morocco〈/a〉〈br〉 (Najid, D., Westphal, M., Hernandez, J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0042.pdf"〉In Memoriam Wilhelm Hiller〈/a〉〈br〉 (Schneider, Götz)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0043.pdf"〉〈i〉Book Reviews〈/i〉〈/a〉〈br〉 (Wilhelm, H., Neubauer, F. M., Schopper, J. R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0044.pdf"〉Joint Two-Dimensional Observations of Ground Magnetic and Ionospheric Electric Fields Associated with Auroral Zone Currents〈/a〉〈br〉 (Inhester, B., Baumjohann, W., Greenwald, R. A., Nielsen, E.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0045.pdf"〉Current Flow in Auroral Forms Responsible for Ps 6 Magnetic Disturbances〈/a〉〈br〉 (Rostoker, G., Apps, K. S.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0046.pdf"〉Correlation of Geomagnetic Activity Indices ap with the Solar Wind Speed and the Southward Interplanetary Magnetic Field〈/a〉〈br〉 (Schreiber, H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0047.pdf"〉High Time-Resolution Correlation Between the Magnetic Field Behaviour at 37 〈i〉R〈/i〉〈sub〉E〈/sub〉 Distance in the Magnetotail Plasma Sheet and Ground Phenomena During Substrom Expansive Phase〈/a〉〈br〉 (Sergeev, V. A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0048.pdf"〉Simultaneous Observations of Energetic Protons Close to the Bow Shock and Far Upstream〈/a〉〈br〉 (Scholer, M., Ipavich, F. M., Gloeckler, G., Hovestadt, D.)〈/a〉〈/li〉 〈li〉〈a href=" https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0049.pdf"〉Non-Adiabatic Expansion of Low-Temperature Solar Wind Radial Temperature Gradients〈/a〉〈br〉 (Geranios, A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0050.pdf"〉Correlation Between Seismic Microactivity, Temperature and Subsidence of Water Level at Reservoirs〈/a〉〈br〉 (Merkler, G., Bock, G., Fuchs, K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0052.pdf"〉〈sup〉40〈/sup〉Ar/〈sup〉39〈/sup〉Ar Dating of Himalayan Rocks from the Mount Everest Region〈/a〉〈br〉 (Kaneoka, Ichiro, Kono, Masaru)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0053.pdf"〉A Comparison of the Thermal and Mechanical Structure of the Lithosphere Beneath the Bohemian Massif and the Pannonian Basin〈/a〉〈br〉 (Onuoha, K. M.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0054.pdf"〉Extremal Models for Electromagnetic Induction in Two-Dimensional Perfect Conductors〈/a〉〈br〉 (Weidelt, P.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0055.pdf"〉On a Type Classification of Lower Crustal Layers Under Precambrian Regions〈/a〉〈br〉 (Jones, A. G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0056.pdf"〉Spherical-Earth Gravity and Magnetic Anomaly Modeling by Gauss-Legendre Quadrature Integration〈/a〉〈br〉 (Frese, R. R. B., Hinze, W. J., Braile, L. W., Luca, A. J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0057.pdf"〉Detection Probabilities for Earthquakes in Sweden〈/a〉〈br〉 (Shapira, A., Kulhánek, O., Wahlström, R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0058.pdf"〉The Geocyclotron Revisited: Potentialities of Modulated Wave Injection〈/a〉〈br〉 (Brinca, A. L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0059.pdf"〉Eine kleine Historie zur Namengebung der Fachdisziplin Geophysik〈/a〉〈br〉 (Buntebarth, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0049/LOG_0060.pdf"〉〈i〉Correction〈/i〉: High Precision Measurement of the Frequency of Mode 〈sub〉0〈/sub〉S〈sub〉0〈/sub〉〈/a〉〈br〉 (Zürn, W., Knopoff, L., Rydelek, P. A.)〈/a〉〈/li〉 〈/body〉 〈/html〉

Description: research

Description: DFG, SUB Göttingen

Description: Dieser Band enthält 78 Artikel zu Themengebieten der Geophysik, veröffentlicht durch die Deutsche Geophysikalische Gesellschaft in dem Jahr 1977.

Description: Inhaltsverzeichnis: Journal of Geophysics 43 〈html〉 〈body〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0012.pdf"〉Editors' Preface〈/a〉〈br〉 (Fuchs, K., Müller, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0013.pdf"〉Full Wave Theory Applied to a Discontinuous Velocity Increase: The Inner Core Boundary〈/a〉〈br〉 (Cormier, V. F., Richards, P. G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0016.pdf"〉Propagation of Elastic Waves in Vertically Inhomogeneous Media〈/a〉〈br〉 (Ungar, A., Ilan, A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0017.pdf"〉Finite-Difference Modelling for P-Pulse Propagation in Elastic Media with Arbitrary Polygonal Surface〈/a〉〈br〉 (Ilan, A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0020.pdf"〉Extension of Matrix Methods to Structures with Slightly Irregular Stratification〈/a〉〈br〉 (Cisternas, A., Jobert, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0021.pdf"〉Modal Approach to Wave Propagation in Layered Media with Lateral Inhomogeneities〈/a〉〈br〉 (Saastamoinen, P. R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0022.pdf"〉On the Propagation of Seismic Pulses in a Porous Elastic Solid〈/a〉〈br〉 (Mainardi, F., Servizi, G., Turchetti, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0023.pdf"〉Three-Dimensional Seismic Ray Tracing〈/a〉〈br〉 (Julian, B. R., Gubbins, D.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0025.pdf"〉On Geophysical Inverse Problems and Constraints〈/a〉〈br〉 (Sabatier, P. C.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0027.pdf"〉On Impulse Response Data and the Uniqueness of the Inverse Problem〈/a〉〈br〉 (Barcilon, V.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0028.pdf"〉Least-Squares Collocation and the Gravitational Inverse Problem〈/a〉〈br〉 (Moritz, H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0029.pdf"〉The Statistical Description and Interpretation of Geophysical Potential Fields Using Covariance Functions〈/a〉〈br〉 (Kautzleben, H., Harnisch, M., Schwahn, W.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0030.pdf"〉A Finite Element Program Package for Electromagnetic Modeling〈/a〉〈br〉 (Kaikkonen, P.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0032.pdf"〉Linear Inverse Problem in Gravity Profile Interpretation〈/a〉〈br〉 (Vigneresse, J. L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0034.pdf"〉Data Seizing and Information Processing〈/a〉〈br〉 (Picard, C. F., Sallantin, J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0035.pdf"〉Formal Morphostructural Zoning of Mountain Territories〈/a〉〈br〉 (Alekseevskaya, M., Gabrielov, A., Gel’fand, I., Gvishiani, A., Rantsman, E.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0036.pdf"〉Three Dimensional Seismic Velocity Anomalies in the Lithosphere〈/a〉〈br〉 (Aki, Keiiti)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0038.pdf"〉The Inversion of Long Range Seismic Profiles〈/a〉〈br〉 (Kennett, B. L. N.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0040.pdf"〉An Oceanic Long Range Explosion Experiment〈/a〉〈br〉 (Orcutt, J. A., Dorman, L. M.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0041.pdf"〉The Upper Mantle Under Western Europe Inferred from the Dispersion of Rayleigh Modes〈/a〉〈br〉 (Nolet, Guust)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0044.pdf"〉Global and Regional Phase Velocities of Long-Period Fundamental Mode Rayleigh Waves〈/a〉〈br〉 (Mitronovas, W.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0045.pdf"〉The Inversion of Surface Wave Dispersion Data with Random Errors〈/a〉〈br〉 (Knopoff, L., Chang, F.-S.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0048.pdf"〉Finite Difference Calculation of Stress Relaxation Earthquake Models〈/a〉〈br〉 (Stöckl, H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0050.pdf"〉On Equivalent Models of Seismic Sources〈/a〉〈br〉 (Jobert, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0051.pdf"〉A Method for Synthesis of the Seismic Coda of Local Earthquakes〈/a〉〈br〉 (Herrmann, R. B.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0055.pdf"〉Application of Two-Timing Methods in Statistical Geophysics〈/a〉〈br〉 (Hasselmann, K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0056.pdf"〉Scattered Waves in the Coda of P〈/a〉〈br〉 (Hudson, J. A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0057.pdf"〉Elastic Wave Propagation in a Highly Scattering Medium – A Diffusion Approach〈/a〉〈br〉 (Dainty, A. M., Toksöz, M. N.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0058.pdf"〉Seismic Energy Transmission in an Intensively Scattering Environment〈/a〉〈br〉 (Nakamura, Yosio)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0060.pdf"〉Scattering of Rayleigh Waves by a Ridge〈/a〉〈br〉 (Sabina, F. J., Willis, J. R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0061.pdf"〉Mean-Field Electrodynamics and Dynamo Theory of the Earth's Magnetic Field〈/a〉〈br〉 (Krause, F.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0064.pdf"〉An Example of Nonlinear Dynamo Action〈/a〉〈br〉 (Busse, F. H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0065.pdf"〉Energetics of the Earth's Core〈/a〉〈br〉 (Gubbins, D.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0066.pdf"〉Equation of State of Liquid Iron at the Earth's Core Conditions〈/a〉〈br〉 (Boschi, E., Mulargia, F.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0067.pdf"〉Lithospheric Slab Penetration into the Lower Mantle beneath the Sea of Okhotsk〈/a〉〈br〉 (Jordan, T. H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0069.pdf"〉〈i〉Abstracts and Short Communications〈/i〉〈/a〉〈br〉〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0068.pdf"〉Phenomenological Representation of Seismic Sources〈/a〉〈br〉 (Backus, G., Mulcahy, M.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0070.pdf"〉The Influence of the Core and the Oceans on the Chandler Wobble〈/a〉〈br〉 (Dahlen, F. A., Smith, M. L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0071.pdf"〉The Earth's Core-Mantle Interface Revisited〈/a〉〈br〉 (Hide, R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0072.pdf"〉Seismic Observations of Structure and Physical Properties of the Subcrustal Lithosphere as Evidence for Dynamical Processes in the Upper Mantle〈/a〉〈br〉 (Fuchs, K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0073.pdf"〉Seismic Anisotropy – a Summary〈/a〉〈br〉 (Crampin, Stuart)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0074.pdf"〉Precise Continuous Monitoring of Seismic Velocity Variations〈/a〉〈br〉 (Bungum, H., Risbo, T., Hjortenberg, E.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0075.pdf"〉On the Computation of Theoretical Seismograms for Multimode Surface Waves〈/a〉〈br〉 (Calcagnile, G., Panza, G. F., Schwab, F., Kausel, E.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0076.pdf"〉On the Excitation of the Earth's Seismic Normal Modes〈/a〉〈br〉 (Vlaar, N. J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0077.pdf"〉Seismic Velocities and Density of an Attenuating Earth〈/a〉〈br〉 (Hart, R. S., Anderson, D. L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0078.pdf"〉A First-Motion Alternative to Geometrical Ray Theory〈/a〉〈br〉 (Chapman, C. H., Dey Sarkar, S. K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0079.pdf"〉Heterogeneous Velocity Structure at the Base of the Mantle〈/a〉〈br〉 (Snoke, J. A., Sacks, I. S.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0080.pdf"〉Heterogeneous velocity structure at the base of the mantle〈/a〉〈br〉 (Sacks, I. S., Snoke, J. A.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0081.pdf"〉Theoretical Seismograms of Core Phases Calculated by a Frequency-Dependent Full Wave Theory, and Their Interpretation〈/a〉〈br〉 (Choy, G. L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0082.pdf"〉Amplitudes of Long-Period PcP, SKS and SKKS and the Structure at the Base of the Mantle and in the Outer Core〈/a〉〈br〉 (Müller, G., Kind, R., Mula, A., Gregersen, S.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0083.pdf"〉Relative Errors in Group Velocity Measurements〈/a〉〈br〉 (Knopoff, L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0084.pdf"〉The Propagation of Plasma Waves in the Jovian Magnetosphere〈/a〉〈br〉 (Denskat, K. U., Neubauer, F. M.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0085.pdf"〉Statistical Theory of Electromagnetic Induction in Thin Sheets〈/a〉〈br〉 (Treumann, R., Schäfer, K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0086.pdf"〉Precursors to P' P' and Upper Mantle Discontinuities〈/a〉〈br〉 (Husebye, E. S., Haddon, R. A. W., King, D. W.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0090.pdf"〉Mantle Heterogeneity and Mislocation Patterns for Seismic Networks〈/a〉〈br〉 (Vermeulen, J. M., Doornbos, D. J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0093.pdf"〉Correlation Between Micro-Activity and Variation of Water Level at the Schlegeis-Reservoir〈/a〉〈br〉 (Blum, R., Bock, G., Fuchs, K., Merkler, G., Widmann, R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0095.pdf"〉Attenuation Coefficients of Acoustic Normal Modes in Shallow Water〈/a〉〈br〉 (Essen, H.-H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0096.pdf"〉Relation of Gravity to Elevation in Zambia〈/a〉〈br〉 (Töpfer, K. D.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0098.pdf"〉Albert Defant (1884 - 1974) 〈/a〉〈br〉 (Krauß, W.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0099.pdf"〉Study of the Structure of the Lower Lithosphere by Explosion Seismology in the USSR〈/a〉〈br〉 (Ryaboy, V. Z.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0102.pdf"〉P-Wave Amplitudes and Sources of Scattering in 〈i〉m〈/i〉〈sub〉b〈/sub〉-Observations〈/a〉〈br〉 (Ringdal, F.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0104.pdf"〉Analyse von Mikroseismikmessungen auf Sylt〈/a〉〈br〉 (Szelwis, R., Janle, P.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0107.pdf"〉Improved Technique for Rapid Interpretation of Gravity Anomalies Caused by Two-Dimensional Sedimentary Basins〈/a〉〈br〉 (Töpfer, K. D.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0109.pdf"〉Investigation of Isostasy by Computing the Correlation Coefficients between Elevations and Bouguer Anomalies〈/a〉〈br〉 (Janle, P.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0110.pdf"〉Geoelectrical Deep Soundings in Southern Africa Using the Cabora Bassa Power Line〈/a〉〈br〉 (Blohm, E. K., Worzyk, P., Scriba, H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0112.pdf"〉Spectral Characteristics of Cross-Field and Two Stream Instability as Revealed by Rocket Borne Studies〈/a〉〈br〉 (Gupta, S. P.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0113.pdf"〉〈i〉Short Communication〈/i〉 Observation of PS Reflections from the Moho〈/a〉〈br〉 (Jacob, A. W. B., Booth, D. C.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0115.pdf"〉〈i〉Book Reviews〈/i〉〈/a〉〈br〉 (Makris, J., Weigel, W.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0116.pdf"〉Planetarische Dynamos〈/a〉〈br〉 (Stix, M.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0117.pdf"〉〈i〉Original Investigations〈/i〉 A Note on the Post-Rosenbluth Quasilinear Diffusion Coefficient in the Ring Current Region〈/a〉〈br〉 (Treumann, R., Grafe, A., Lehmann, H.-R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0118.pdf"〉Remote Sensing Experiment for Magnetospheric Electric Fields Parallel to the Magnetic Field〈/a〉〈br〉 (Wilhelm, K.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0119.pdf"〉A Study of the Echzell/Wetterau Earthquake of November 4, 1975〈/a〉〈br〉 (Neugebauer, H. J., Tobias, E.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0121.pdf"〉Thermoelastic Deformations of a Half-Space – A Green's Function Approach〈/a〉〈br〉 (Müller, G.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0123.pdf"〉Gravity Variations with Time in Northern Iceland 1965–1975〈/a〉〈br〉 (Torge, W., Drewes, H.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0125.pdf"〉High Resolution Near Surface Reflection Measurements Using a Vertical Array Technique〈/a〉〈br〉 (Schepers, R.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0127.pdf"〉Ausbreitung von Rayleigh-Kanalwellen in Steinkohleflözen – Modellseismische Untersuchungen〈/a〉〈br〉 (Freystätter, S., Dresen, L.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0129.pdf"〉Comment on: Hydromagnetic Waves in a Non-Uniform Plasma〈/a〉〈br〉 (Kupfer, E.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0130.pdf"〉〈i〉Book Reviews〈/i〉〈/a〉〈br〉 (Kisslinger, C., Klußmann, J.)〈/a〉〈/li〉 〈li〉〈a href="https://gdz.sub.uni-goettingen.de/download/pdf/PPN1015067948_0043/LOG_0131.pdf"〉〈i〉Erratum〈/i〉 Full Wave Theory Applied to a Discontinuous Velocity Increase: The Inner Core Boundary〈/a〉〈br〉 (Cormier, V. F., Richards, P. G.)〈/a〉〈/li〉 〈/body〉 〈/html〉

Description: Dynamo Theory

Description: research

Description: DFG, SUB Göttingen

Description: High-resolution seismic reflection, magnetic and gravity data, acquired offshore of Etna volcano, provide a new insight to understanding the relationship between tectonics and spatial-temporal evolution of volcanism. The Timpe Plateau, a structural high pertaining to the Hyblean foreland domain, located offshore of southeastern Mt. Etna, is speckled by volcanics and strongly affected by strike-slip tectonics. Transpressive deformation produced a push-up and a remarkable shortening along WNW-ESE to NW-SE trending lineaments. Fault segments, bounding basinal areas, show evidence of positive tectonic inversion, suggesting a former transtensive phase. Transtensive tectonics favoured the emplacement of deep magmatic intrusive bodies and Plio-Quaternary scattered volcanics through releasing zones. The continuing of wrench tectonics along different shear zones led to the migration of transtensive regions in the Etna area and the positive inversion of the former ones, where new magma ascent was hampered. This process caused the shifting of volcanism firstly along the main WNW-ESE trending "Southern Etna Shear Zone", then towards the Valle del Bove and finally up to the present-day stratovolcano.

Description: Published

Description: 12125

Description: 1T. Struttura della Terra

Description: 1V. Storia eruttiva

Description: 2V. Struttura e sistema di alimentazione dei vulcani

Description: 1A. Geomagnetismo e Paleomagnetismo

Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare

Description: 2TR. Ricostruzione e modellazione della struttura crostale

Description: JCR Journal

Description: Global cloud-resolving models (GCRMs) are a new category of atmospheric global models designed to solve different flavors of the nonhydrostatic equations through the use of kilometer-scale global meshes. GCRMs make it possible to explicitly simulate deep convection, thereby avoiding the need for cumulus parameterization and allowing for clouds to be resolved by microphysical models responding to grid-scale forcing. GCRMs require high-resolution discretization over the globe, for which a variety of mesh structures have been proposed and employed. The first GCRM was constructed 15 years ago, and in recent years, other groups have also begun adopting this approach, enabling the first intercomparison studies of such models. Because conventional general circulation models (GCMs) suffer from large biases associated with cumulus parameterization, GCRMs are attractive tools for researchers studying global weather and climate. In this review, GCRMs are described, with some emphasis on their historical development and the associated literature documenting their use. The advantages of GCRMs are presented, and currently existing GCRMs are listed and described. Future prospects for GCRMs are also presented in the final section.

Description: The InSight spacecraft was proposed to be a build-to-print copy of the Phoenix vehicle due to the knowledge that the lander payload would be similar and the trajectory would be similar. However, the InSight aerothermal analysts, based on tests performed in CO2 during the Mars Science Laboratory mission (MSL) and completion of Russian databases, considered radiative heat flux to the aftbody from the wake for the first time for a US Mars mission. The combined convective and radiative heat flux was used to determine if the as-flown Phoenix thermal protection system (TPS) design would be sufficient for InSight. All analyses showed that the design would be adequate. Once the InSight lander was successfully delivered to Mars on November 26, 2018, work began to reconstruct the atmosphere and trajectory in order to evaluate the aerothermal environments that were actually encountered by the spacecraft and to compare them to the design environments.The best estimated trajectory (BET) reconstructed for the InSight atmospheric entry fell between the two trajectories considered for the design, when looking at the velocity versus altitude values. The maximum heat rate design trajectory (MHR) flew at a higher velocity and the maximum heat load design trajectory (MHL) flew at a lower velocity than the BET. For TPS sizing, the MHL trajectory drove the design. Reconstruction has shown that the BET flew for a shorter time than either of the design environments, hence total heat load on the vehicle should have been less than used in design. Utilizing the BET, both DPLR and LAURA were first run to analyze the convective heating on the vehicle with no angle of attack. Both codes were run with axisymmetric, laminar flow in radiative equilibrium and vibrational non-equilibrium with a surface emissivity of 0.8. Eight species Mitcheltree chemistry was assumed with CO2, CO, N2, O2, NO, C, N, and O. Both codes agreed within 1% on the forebody and had the expected differences on the aftbody. The NEQAIR and HARA codes were used to analyze the radiative heating on the vehicle using full spherical ray-tracing. The codes agreed within 5% on most aftbody points of interest.The LAURA code was then used to evaluate the conditions at angle of attack at the peak heating and peak pressure times. Boundary layer properties were investigated to confirm that the flow over the forebody was laminar for the flight.Comparisons of the aerothermal heating determined for the reconstructed trajectory to the design trajectories showed that the as-flown conditions were less severe than design

Description: A series of eight olivine specimens were fabricated by hot-pressing at 1200 degrees Celsius and 300 megapascals (MPa). Each hot-pressed specimen was then wrapped in Pt, Ni or NiFe foil to vary oxygen fugacity (fO2), and interrogated via forced torsional oscillation. Mechanical testing was conducted at 10 oscillation periods between 1 and 1000 seconds, at a confining pressure of 200 MPa, during a slow staged-cooling from a maximum temperature of 1200 degrees Celsius to room temperature. After mechanical testing, each specimen was axially sectioned and EBSD (Electron BackScatter Diffraction) was used for the determination of the representative grain size, and grain size distribution of each sample. In addition, each longitudinal section was mapped via FTIR (Fourier Transform InfraRed spectroscopy) to determine the spatial distribution and concentrations of chemically bound and molecular water. Amongst these specimens, chemically bound water contents were observed to vary between 0 and 1150 atom ppm (parts per million) H/Si, and molecular water concentrations varied between 0 and 245 atom ppm H/Si. Our forced-oscillation results demonstrate that the measured magnitude of anelastic relaxation within the experimental window of oscillation periods is unrelated to the water content. Rather, a relationship was observed between the magnitude of anelastic relaxation and the prevailing redox conditions, which is influenced by the choice of metal sleeving used during the mechanical test. Further, regardless of water content or metal sleeving, each specimen exhibits coupled variations in shear modulus and dissipation within the observational window, indicative of high-temperature background behavior, that can be described by a Burgers-type model. During initial fitting of the Burgers models, the unrelaxed shear modulus at a reference temperature of 900 degrees Celsius (G (sub UR)) and the temperature derivative of the unrelaxed shear modulus (dG (sub U)/dT), were treated as adjustable parameters. For all Fe-bearing olivine samples (but not a hydrous and oxidized Fe-free sample) we observe deficits of G (sub UR), and increased values of dG (sub U)/dT, relative to the expected elastic (anharmonic) behavior of Fo90 olivine. This behavior is indicative of anelastic relaxation occurring at shorter periods than observable within the window of oscillation periods used in the mechanical test. Moving towards a comprehensive seismologically applicable Burgers model, which includes this newly observed effect of redox conditions on anelastic relaxation, we will present our progress in reconciling truly anharmonic and elastic behavior of Fo (sub 90) olivine with our observed forced-oscillation data.

Description: Improvements and results of a new method are presented that computes a pre-test estimate of the precision error of the drag coefficient of a wind tunnel model. The error estimate is defined as the part of the drag coefficient's precision error that is primarily associated with the precision error of the angle of attack measurement and physical characteristics of the chosen strain-gage balance. The method indirectly describes the precision error of the angle of attack measurement by using an assumed balance gage output variation of one microV/V. The physical characteristics of the balance, on the other hand, are described by partial derivatives of the axial and normal forces with respect to the strain-gage outputs. These derivatives can directly be obtained from the data reduction matrix of the balance. The precision error estimate itself is calculated by applying a simple explicit equation that uses the model reference area, the dynamic pressure, the angle of attack, the coefficients of the linear terms of the data reduction matrix, and the electrical output variation of one microvolt per volt as input. Precision errors at constant angle of attack may be visualized as contour plots by plotting them, for example, versus the Mach number and the total pressure. Characteristics of NASA's MC60E balance are used in combination with the reference area of a generic wind tunnel model in order to demonstrate that error estimates are independent of both the balance load format and the units chosen for the description of balance loads, model reference area, and the dynamic pressure. Finally, experimental data from a wind tunnel test of the Ames Check Standard Model in the NASA Ames 11-foot Transonic Wind Tunnel illustrates the application of the method to real-world test data.

Description: Wake vortex spacing standards constrict the terminal area throughput and impose severe constraints on the overall capacity and efficiency of the National Airspace System. For more than two decades starting in the early 1990s, the National Aeronautics and Space Administration conducted extensive research on characterizing the formation and evolution of aircraft wakes. This multidisciplinary work included comprehensive field experiments (Pruis et al. 2016), flight tests (Vicroy et al. 1998), and wind tunnel tests (Rossow 1994; Chow et al. 1997). Parametric studies using large eddy simulations (Proctor 1998; Proctor et al. 2006) were conducted in order to develop fast-time models for the prediction of wake transport and decay (Ahmad et al. 2016). Substantial effort was spent on the formulation of acceptable vortex hazard metrics (Tatnall 1995; Hinton and Tatnall 1997). Several wake encounter severity metrics have been suggested in the past, which include the wake circulation strength, vortex-induced rolling moment coefficient (Clv), bank angle, and the roll control ratio (Tatnall 1995; Hinton and Tatnall 1997; Van der Geest 2012). The vortex-induced rolling moment coefficient introduced by Bowles and Tatnall (Tatnall 1995; Gloudemans et al. 2016) has been used extensively for risk and safety analysis of newly proposed air traffic management concepts and procedures. The original method of Bowles and Tatnall assumed a constant wing loading (the wing lift-curve slope, CL is constant), which resulted in an overestimation of the vortexinduced rolling moment coefficient. Bowles (2014) suggested a correction to the original method that provides more accurate values of Clv and which is also consistent with the underlying physics of the problem. The overestimation of Clv in the original method can be corrected by assuming an elliptical lift distribution. Figure 1.1 illustrates the correction in Clv achieved by the modified method.

Description: Since its development by Wark and Watson (2006), the Ti-in-quartz geothermometer (TitaniQ) has been continuously refined and applied to a variety of lithologies from different crustal settings. Assuming quartz crystallized and incorporated Ti under equilibrium conditions and providing TiO2 activity (alpha (sub TiO2)) is reasonably constrained, crystallization temperatures at typical crustal pressures can be calculated. In turn, when crystallization temperatures are independently constrained, Ti-in-quartz can be used as a geobarometer. Here we explore the application of this technique to impact lithologies. Quartz is ubiquitous in terrestrial impact structures in upper crustal settings and can also form as a post-impact hydrothermal mineral. Together with other geothermometers, such as Ti-in-zircon, Ti-in-quartz can potentially help constrain the temperature-pressure conditions during the formation of the pre-impact target rock at terrestrial impact structures, as well as impact-produced and hydrothermally-altered lithologies. This work presents the first systematic Ti-in-quartz study of impactites and granitoid target rocks from the approximately180-kilometer-diameter, end-Cretaceous Chicxulub crater on the Yucatan Peninsula, Mexico, thereby placing new constraints on the emplacement of felsic plutons within the Maya Block in the Paleozoic, impact melt crystallization at approximately 66 Ma (million years ago), and post-impact hydrothermal overprint inside the Chicxulub crater.

Description: National airspace, the management for access and operation of these vehicles is required. This management is being developed under the unmanned aircraft system traffic management system (UTM) program. To determine the aerodynamic characteristics of drones, wind tunnel experiments and computation fluid dynamic (CFD) analysis have been conducted. These experiments and analyses are undertaken to understand the flight capabilities of these vehicles in variable head and cross wind conditions. The results of these investigations will provide metrics for the safe operation of these vehicles in and around civil populations and in urban settings. The focus of this paper is to model a drone installed in a wind tunnel for varying pitch attitudes and rotor rpm settings. Specifically, the IRIS drone is modeled in the NASA-Ames 7x10 ft. W/T. The tunnel mounting hardware and the tunnel enclosure are modeled with the IRIS drone geometry. The rotors of the drone are modeled using two methodologies: a rotor disk model and individual blade representations. The results of the analysis are compared with available experimental data to validate the computational approach.

Description: The Mid-Lift-to-Drag ratio Rigid Vehicle (MRV) is a candidate in the NASA multi-center effort to determine the most cost effective vehicle to deliver a large-mass payload to the surface of Mars for a human mission. Products of this effort include six-degree-of-freedom (6DoF) entry-to-descent trajectory performance studies for each candidate vehicle. These high fidelity analyses help determine the best guidance and control (G&C) strategies for a feasible, robust trajectory. This paper presents an analysis of the MRV's G&C design by applying common entry and descent associated uncertainties using a Fully Numerical Predictor-corrector Entry Guidance (FNPEG) and tunable Apollo powered descent guidance.

Description: Artificial ice shapes of various geometric fidelity were tested on a wing model based on the Common Research Model. Low Reynolds number test were conducted at Wichita State University's Walter H. Beech Memorial Wind utilizing an 8.9% scale model, and high Reynolds number tests were conducted at ONERA's F1 wind tunnel utilizing a 13.3% scale model. Several identical geometrically-scaled ice shapes were tested at both facilities, and the results were compared at overlapping Reynolds and Mach numbers. This was to ensure that the results and trends observed at low Reynolds number could be applied and continued to high, near-flight Reynolds number. The data from Wichita State University and ONERA F1 agreed well at matched Reynolds and Mach numbers. The lift and pitching moment curves agreed very well for most configurations. This confirmed results from previous tests with other ice shapes that indicated the data from the low Reynolds number tests could be used to understand ice-swept-wing aerodynamics at high Reynolds number. This allows ice aerodynamics testing to be performed at low Reynolds number facilities with much lower operating costs and generate results that are applicable to flight Reynolds number.

Description: The history of the Greenland Ice Sheet has been influenced by the geodynamic response to ice sheet fluctuations, and this interaction may help explain past deglaciations under modest climate forcing. We hypothesize that when the Iceland hot spot passed beneath northcentral Greenland, it thinned the lithosphere and left anomalous heat likely with partially melted rock; however, it did not break through the crust to supply voluminous flood basalts. Subsequent PlioPleistocene glacialinterglacial cycles caused large and rapidly migrating stresses, driving dike formation and other processes that shifted melted rock toward the surface. The resulting increase in surface geothermal flux favored a thinner, fasterresponding ice sheet that was more prone to deglaciation. If this hypothesis of control through changes in geothermal flux is correct, then the longterm (10 (sup 5) to 10 (sup 6) years) trend now is toward lower geothermal flux, but with higherfrequency (less than or equal to 10( sup 4) to 10 (sup 5) years) oscillations linked to glacialinterglacial cycles. Whether the geothermal flux is increasing or decreasing now is not known but is of societal relevance due to its possible impact on ice flow. We infer that projections of the future of the ice sheet and its effect on sea level must integrate geologic and geophysical data as well as glaciological, atmospheric, oceanic, and paleoclimatic information.

Description: The intermediate wakes of thin flat plates with circular trailing edges (TEs) are investigated here with direct numerical simulations (DNSs). The separating boundary layers are turbulent in all cases. The near wake in two thin-plate cases (IN & NS), with a focus on the vortex shedding process, was explored in a recent article. Intermittent shedding was observed in Case IN. Case NS, with half the TE diameter of Case IN, was an essentially non-shedding case. A third case (ST) with a sharp trailing edge was also investigated and found to exhibit an intermittent wake instability. The objectives of the present study are twofold. The first is to determine if the wake instability found in Case ST exists in Cases IN and NS as well. The second is to provide the distributions of the turbulent normal intensities and shear stress in the wake and to understand these distributions via the budget terms in the corresponding transport equations. The results show that both Cases IN & NS exhibit a wake instability in the intermediate wake region, that is similar to that found earlier in Case ST. We note that in Case IN, the presence of an intermediate-wake instability results in the co-existence of two different types of instability within a single wake. The distributions of the turbulent normal intensities and shear stress, and the budget terms for the streamwise intensity are included and discussed here. All the budget terms contribute appreciably to the overall budget in the transport equation for streamwise normal intensity.

Description: US Army MC-4/5 ram-air parachutes were tested in the 80- by 120-Ft test section of the National Full-Scale Aerodynamics Complex. Arrays of targets on the upper and lower surfaces of the central cell of the canopies were measured by stereo photogrammetry, and the target positions were used to estimate both the shape of the cell and angle of attack of the canopy. Forces and moments were measured by a six-axis load cell. Based on the photogrammetry and load-cell measurements, the relationships between lift, drag, and angle of attack were determined over a range of trailing-edge flap deflections, front riser lengths, and free-stream airspeeds. This paper describes the test, with an emphasis on the photogrammetry measurements, and presents a summary of results.

Description: The Advanced Supersonic Parachute Inflation Research Experiments (ASPIRE) project waslaunched to develop the capability for testing supersonic parachutes at Mars-relevant conditions.Three initial parachute tests, targeted as a risk-reduction activity for NASA's upcomingMars2020 mission, successfully tested two candidate parachute designs and provided valuabledata on parachute inflation, forces, and aerodynamic behavior. Design of the flight tests dependedon flight mechanics simulations which in turn required aerodynamic models for the payload, andthe parachute. Computational Fluid Dynamics (CFD) was used to generate these models preflightand are compared against the flight data after the tests. For the payload, the reconstructedaerodynamic behavior is close to the pre-flight predictions, but the uncertainties in thereconstructed data are high due to the low dynamic pressures and accelerations during the flightperiod of comparison. For the parachute, the predicted time to inflation agrees well with the preflightmodel; the peak aerodynamic force and the steady state drag on the parachute are withinthe bounds of the pre-flight models, even as the models over-predict the parachute drag atsupersonic Mach numbers. Notably, the flight data does not show the transonic drag decreasepredicted by the pre-flight model. The ASPIRE flight tests provide previously unavailablevaluable data on the performance of a large full-scale parachute behind a slender leading bodyat Mars-relevant Mach number, dynamic pressure and parachute loads. This data is used topropose a new model for the parachute drag behind slender bodies to aid future experiments.

Description: Objectives: Reliable evaluation of mass flow rates through permeable boundaries - Estimate and control discretization error- Consider both computational domain outflow and inflow- Applicable to simulating propulsion-system effects, as well as secondary flow paths - Explore feasibility of handling more general outputs at domain boundaries. Design optimization subject to mass-flow-rate constraints - Improve aerodynamic performance and reduce noise due to sonic boom - Control discretization error in design space to improve confidence in final designs.

Description: Studies of many objects in petrographic thin section, such as melt inclusions in igneous rocks, chondrules and Ca-Al rich inclusions in chondritic meteorites, or clasts in lunar and other breccias, require or can benefit from knowledge of their bulk compositions. Given the scarcity of these materials, the reluctance of curators to provide more abundant material, and the extreme difficulty of cleanly separating such objects from their rock matrices, geochemical and cosmochemical studies need the ability to determine their bulk compositions from in situ methods, such as defocused beam analysis, or quantitative chemical mapping by electron beam methods.

Description: A group called as Martian meteorites is composed of shergottites, nakhlites, chassignites, and orthopyroxenite, and they are thought to be derived from Mars. Among the Martian meteorites nakhlites and chassignites show similar cosmic-ray exposure (CRE) ages of 11-12 million years, although petrologic characteristics are very different between them. Both nakhlites and chassignites indicate similar cooling rates, and would have cooled in identical scale of igneous bodies. However, the relationship between nakhlites and chassignites is still unclear, although they might have ejected at the same time, i.e., by accidentally coincidental impact events which occurred at different places on Mars or by a single impact which excavated both nakhlites and chassignites residing in a relatively small area. Here we propose that the chassignites show a genetically close relationship with nakhlites, i.e., both groups could be located within a relatively narrow area from where a single impact could have launched those meteorites, based on noble gas data obtained in our laboratory. If chassignites were really ejected with nakhlites by a single impact, both types of meteorites will provide us with geological/petrological profile in the area where both pyroxene-rich lava (nakhlites) and dunite-rich rocks (chassignites) are located close to the Martian surface. [i.e. discusses NWA 2737, etc. (Martian meteorites that fell in Northwest Africa)]

Description: Eight olivine specimens were fabricated by use of a solgel method and hot-pressing at 1200 degrees Centigrade and 300 megapascals (MPa) inside of welded Pt capsules. Each hot-pressed specimen was then recovered, precision ground, and wrapped in Pt, Ni or NiFe foil to vary oxygen fugacity (fO2) during the subsequent forced torsional oscillation measurements. Mechanical testing was conducted at 10 oscillation periods between 1 and 1000 seconds, at a confining pressure of 200 MPa, during a slow staged-cooling from a maximum temperature of 1200 degrees Centigrade down to room temperature. After mechanical testing, each specimen was axially sectioned and EBSD (Electron BackScatter Diffraction) was used for the determination of the representative grain size, and grain size distribution of each sample. In addition, each longitudinal section was mapped via FTIR (Fourier Transform Infrared Spectroscopy) to determine the spatial distribution and concentrations of chemically bound and molecular water. Amongst these eight specimens, chemically bound water contents were observed to vary between 0 and 1150 atom parts per million (ppm) H/Si, and molecular water concentrations varied between 0 and 245 atom ppm H/Si. Our forced-oscillation results demonstrate that the measured magnitude of anelastic relaxation within the experimental window of oscillation periods is unrelated to the water content. Rather, a relationship was observed between the magnitude of anelastic relaxation and the prevailing redox conditions, which is influenced by the choice of metal sleeving used during the mechanical test. Further, regardless of water content or metal sleeving, each specimen exhibits coupled variations in shear modulus and dissipation within the observational window, indicative of high-temperature background behavior, that can be described by a Burgers-type model. During initial fitting of the Burgers models, the unrelaxed shear modulus at a reference temperature of 900C (elastic unloading/reloading shear modulus G (sub UR)) and the temperature derivative of the unrelaxed shear modulus (dGU/dT), were treated as adjustable parameters. For all Fe-bearing olivine samples we observe deficits of G (sub UR) and increased values of dGU/dT, relative to the expected elastic (anharmonic) behavior for Fo (Forsterite content percentage) (sub 90) olivine. This behavior is indicative of anelastic relaxation occurring at shorter periods than observable within the window of oscillation periods used in the mechanical test. Moving towards a comprehensive and seismologically applicable Burgers model, which includes this newly observed effect of redox conditions on anelastic relaxation, we will present our progress on reconciling truly anharmonic and elastic behavior of Fo (sub 90) olivine with our observed forced-oscillation data.

Description: The observed Earth's polar motion on decadal time scales has long been conjectured to be excited by the exchange of equatorial angular momentum between the solid mantle and the fluid outer core, via the mechanism of electromagnetic (EM) core-mantle coupling. However, past estimations of the EM coupling torque from surface geomagnetic observations is too weak to account for the observed decadal polar motion. Our recent estimations from numerical geodynamo simulations have shown the opposite. In this paper, we re-examine in detail the EM coupling mechanism and the properties of the magnetic field in the electrically conducting lower mantle (characterized by a thin D-layer at the base of the mantle). Our simulations find that the toroidal field in the D-layer from the induction and convection of the toroidal field in the outer core could be potentially much stronger than that from the advection of the poloidal field in the outer core. The former, however, cannot be inferred from geomagnetic observations at the Earth's surface, and is missing in previous EM torque estimated from geomagnetic observations. Our deduction suggests further that this field could make the actual EM coupling torque sufficiently strong, at approximately 5 10(exp 19) Nm, to excite, and hence explain, the decadal polar motion to magnitude of approximately 10 mas.

Description: The observation that arc magmas are the most oxidized on Earth have led petrologists to question whether the subduction process might cause oxidation of the sub-arc mantle source. A strong correlation between the input of slab-derived aqueous fluid and Fe3(+)/Fe in arc magmas has led to the hypothesis that slab fluids may facilitiate the transfer of redox potential from oxidized slab material to mantle wedge and subsequently to primary arc melts. Despite this intuitive link, identifying an efficient and ubiquitous chemical process to transfer oxidation state in slab fluids has been challenging. Pure H2O alone is an inefficient oxidizer in the mantle, necessitating another oxidant within the fluid. Commonly invoked components include S or C, which are likely heterogeneously distributed within subducting slabs, and direct transfer of Fe3(+), which is only possible in very solute-rich fluids. Here we present a new mechanism to explain the oxidation of the sub-arc mantle by slab-derived aqueous fluid, wherein dissolved H(+)(aq) is reduced to H2(aq). Redox equilibrium is satisfied by electron transfer from Fe2(+)(s), which is oxidized in the rock to Fe3(+)(s) in the reaction: 2Fe2(+)(s) + 2H(+)(aq) = 2Fe3(+)(s) + H2(aq). This simple reaction was previously overlooked due to the assumption that all H must be bound by H2O molecules (i.e., no dissolved H), applicable to a pure H2O fluid, but not one with a solute load as addressed here. The application of thermodynamic modeling tools from aqueous geochemistry (DEW, EQ3/6) to mantle petrology predicts this reaction between mantle rock and slab fluid with our own experimentally constrained chemistry and fO2 (QFM+2). Mass transfer model results show an increase in Fe3(+)/Fe in mantle rock from MORB- like (0.15) to arc-like (0.20.3) values at reasonable fluid fluxes, co-incident with increasing H2 activity in the fluid. This can explain the stark correlation between slab fluid input into the mantle wedge and the observed fO2 of arc magmas. Moreover, it does not require diffusion of hydrogen out of the system. Instead, H2 remains dissolved in fluid in equilibrium with oxidized mantle rock.

Description: The experimental, fully electric X-57 Maxwell is designed to enable lower energy con-sumption at cruise compare to a fuel burning baseline. This is to be achieved using a sumof subsystem benefits incorporated in the electric, airframe, and propulsion systems. AMission Planning Tool captures the three stages of X-57 development in order to assess thedesign of each subsystem in the context of the whole aircraft. The Mission Planning Toolfor the fully electric X-57 Maxwell captures the aerodynamics, propulsion, heat transfer,and power system of the aircraft with trajectory optimization capabilities. It is able tomodel these subsystems through all phases of flight, from taxi to landing. Through thismultidisciplinary approach, we are able to predict the benefit of each subsystem and theeffect of key design assumptions and how the aircraft will react if they are not met or ex-ceeded. As the aircraft progresses and systems are tested, we can use the Mission PlanningTool to continue to predict performance. This paper details the continued development ofthe X-57 Mission Planning Tool and demonstrates its capabilities.

Description: Compound extremes such as cooccurring soil drought (low soil moisture) and atmospheric aridity (high vapor pressure deficit) can be disastrous for natural and societal systems. Soil drought and atmospheric aridity are 2 main physiological stressors driving widespread vegetation mortality and reduced terrestrial carbon uptake. Here, we empirically demonstrate that strong negative coupling between soil moisture and vapor pressure deficit occurs globally, indicating high probability of cooccurring soil drought and atmospheric aridity. Using the Global Land Atmosphere Coupling Experiment (GLACE)-CMIP5 experiment, we further show that concurrent soil drought and atmospheric aridity are greatly exacerbated by land atmosphere feedbacks. The feedback of soil drought on the atmosphere is largely responsible for enabling atmospheric aridity extremes. In addition, the soil moistureprecipitation feedback acts to amplify precipitation and soil moisture deficits in most regions. CMIP5 models further show that the frequency of concurrent soil drought and atmospheric aridity enhanced by landatmosphere feedbacks is projected to increase in the 21st century. Importantly, land atmosphere feedbacks will greatly increase the intensity of both soil drought and atmospheric aridity beyond that expected from changes in mean climate alone.

Description: Atmospheric motion vectors (AMVs), derived by tracking patterns, represent the winds in a layer characteristic of the pattern. AMV height (or pressure), important for applications in atmospheric research and operational meteorology, is usually assigned using observed IR brightness temperatures with a modeled atmosphere and can be inaccurate. Stereoscopic tracking provides a direct geometric height measurement of the pattern that an AMV represents. We extend our previous work with multi-angle imaging spectroradiometer (MISR) and GOES to moderate resolution imaging spectroradiometer (MODIS) and the GOES-R series advanced baseline imager (ABI). MISR is a unique satellite instrument for stereoscopy with nine angular views along track, but its images have a narrow (380 km) swath and no thermal IR channels. MODIS provides a much wider (2330 km) swath and eight thermal IR channels that pair well with all but two ABI channels, o e ring a rich set of potential applications. Given the similarities between MODIS and VIIRS, our methods should also yield similar performance with VIIRS. Our methods, as enabled by advanced sensors like MODIS and ABI, require high-accuracy geographic registration in both systems but no synchronization of observations. AMVs are retrieved jointly with their heights from the disparities between triplets of ABI scenes and the paired MODIS granule. We validate our retrievals against MISR-GOES retrievals, operational GOES wind products, and by tracking clear-sky terrain. We demonstrate that the 3D-wind algorithm can produce high-quality AMV and height measurements for applications from the planetary boundary layer (PBL) to the upper troposphere, including cold-air outbreaks, wildfire smoke plumes, and hurricanes.

Description: NASAs Advanced Air Transport Technology (AATT) project is investigating boundary layer ingesting (BLI) propulsors for advanced subsonic commercial vehicle concepts to enable the reduction of fuel burn. A multidisciplinary team of researchers from NASA, United Technologies Research Center (UTRC), Virginia Polytechnic University, and the Air Force Arnold Engineering Development Complex developed and tested an embedded BLI inlet and distortion-tolerant fan (BLI2DTF) system in the NASA Glenn Research Center (GRC) 8- foot by 6-foot (8x6) transonic wind tunnel. The test demonstrated the component performance goals necessary for an overall fuel burn reduction of 3 to 5 percent on a large hybrid wing body (HWB) aircraft. Special test equipment, including a raised floor with flow effectors and a bleed system, was developed for use in the 8x6 to produce the appropriate incoming boundary layer representative of an HWB application. Detailed measurements were made to determine the inlet total pressure loss and distortion, fan stage efficiency, and aeromechanic performance including blade vibration stress and displacement response. Results from this test were used as input to a vehicle-level system study performed by the AATT project to assess the impact of BLI on an alternative advanced concept aircraft referred to as the NASA D8 (ND8), which is somewhat similar to the HWB in its integration of the propulsor. This paper will provide an overview of the project timeline, special test equipment needed in the wind tunnel to develop the appropriate incoming boundary layer, and the difficulties in designing a propulsor for the test. The paper will conclude with some representative aerodynamic and aeromechanic data from the test itself and conclude with how this data was used in the ND8 system study.

Description: This manual describes the installation and execution of FUN3D version 13.6, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

Description: _NASA's Advanced Air Transport Technology (AATT) project is investigating boundary layer ingesting (BLI) propulsors for advanced subsonic commercial vehicle concepts to enable the reduction of fuel burn. A multidisciplinary team of researchers from NASA, United Technologies Research Center (UTRC), Virginia Polytechnic University, and the Air Force Arnold Engineering Development Complex developed and tested an embedded BLI inlet and distortion-tolerant fan (BLI2DTF) system in the NASA Glenn Research Center (GRC) 8-foot by 6-foot (8x6) transonic wind tunnel. The test demonstrated the component performance goals necessary for an overall fuel burn reduction of 3 to 5 percent on a large hybrid wing body (HWB) aircraft. Special test equipment, including a raised floor with flow effectors and a bleed system, was developed for use in the 8x6 to produce the appropriate incoming boundary layer representative of an HWB application. Detailed measurements were made to determine the inlet total pressure loss and distortion, fan stage efficiency, and aeromechanic performance including blade vibration stress and displacement response. Results from this test were used as input to a vehicle-level system study performed by the AATT project to assess the impact of BLI on an alternative advanced concept aircraft referred to as the NASA D8 (ND8), which is somewhat similar to the HWB in its integration of the propulsor. This paper will provide an overview of the project timeline, special test equipment needed in the wind tunnel to develop the appropriate incoming boundary layer, and the difficulties in designing a propulsor for the test. The paper will conclude with some representative aerodynamic and aeromechanic data from the test itself and conclude with how this data was used in the ND8 system study.

Description: Thermal Protection System (TPS) modeling requires accurate representation and prediction of the thermomechanical behavior of ablative materials. State-of-the-art TPS materials such as Phenolic Impregnated Carbon Ablator (PICA) have a proven flight record and demonstrate exceptional capabilities for handling extreme aerothermal heating conditions. The constant push for lightweight materials that are flexible in their design and performance, and hence allow for a wide range of mission profiles, has led NASA over the past years to develop its Heatshield for Extreme Entry Environment Technology (HEEET). HEEET is based primarily on a dual layer woven carbon fiber architecture and the technology has successfully been tested in arc-jet facilities. These recent developments have sparked interest in the accurate micro-scale modeling of composite weave architectures, to predict the structural response of macro-scale heatshields upon atmospheric entry. This effort can be extended to incorporate in-depth failure mechanics analyses as a result of local thermal gradients or high-velocity particle impact.

Description: We present the first quantitative calculations of thermospheric heating and cooling times for geomagnetic storms of different intensity, including extreme events. We utilize the neutral mass density database of the CHAllenging Minisatellite Payload and Gravity Recovery And Climate Experiment missions to produce thermospheric global system response to geomagnetic storms caused by coronal mass ejections via superposed epoch analysis during May 2001 to December 2015. Storm events are grouped in five different categories based on the minimum value of the SYMH index. We calculate the time from storm onset for the thermosphere to reach maximum intensification (heating time) and the time from onset for the thermosphere to recover (cooling time). We find that heating and cooling times decrease as storm intensity increases and the effect is more pronounced for the cooling times. For extreme storms, the thermospheric heating time is 9.5 hr, while the cooling time is 22 hr.

Description: NASA successfully demonstrated next generation SLR, VLBI, and GNSS using the GGAO prototypes.Tier 1 deployment of next generation stations is underway: KPGO (Kokee Park, Hawaii); VGOS station operational; VGOS station at McDonald Observatory, Texas nearly operational; build of long-lead items for first 3 SLR stations underway. Planning and discussions with international partners for Tier 2 deployment underway. Plan for Decadal Survey responsive deployment acceleration under review by NASA.

Description: Prediction and control of the onset of transition and the associated variation in aerothermodynamic parameters in high-speed flows is key to optimize the performance and design of Thermal Protection Systems (TPS) of next-generation aerospace vehicles [1]. Boundary Layer Transition (BLT) characteristics can influence the surface heating budget determining the TPS thickness and consequently its weight penalty. Ablative heatshields are designed to alleviate the high heat flux at the surface through pyrolysis of their polymeric matrix and subsequent fiber ablation [2]. Pyrolysis leads to out-gassing and non-uniform ablation lead to surface roughness, both of which are known to influence the transition process. An ablator impacts BLT through three main routes: gas injecting into the boundary layer from the wall, changing the surface heat transfer due to wall-flow chemical reactions, and modifying surface roughness [3]. In preparation to Mars 2020 mission post-flight analysis, the predictive transition capability has been initiated toward hard-coupling porous material response analysis and aerothermal environment calculation.

Description: The Mars Science Laboratory (MSL) Entry, Descent and Landing Instrumentation (MEDLI) collected in-flight data largely used by the ablation community to verify and validate physics-based models for the response of the Phenolic Impregnated Carbon Ablator (PICA) material [1-4]. MEDLI data were recently used to guide the development of NASAs high-fidelity material response models for PICA, implemented in the Porous material Analysis Toolbox based on OpenFOAM (PATO) software [5-6]. A follow-up instrumentation suite, MEDLI2, is planned for the upcoming Mars 2020 mission [7] after the large scientific impact of MEDLI. Recent analyses performed as part of MEDLI2 development draw the attention to significant effects of a protective coating to the aerothermal response of PICA. NuSil, a silicone-based overcoat sprayed onto the MSL heatshield as contamination control, is currently neglected in PICA ablation models. To mitigate the spread of phenolic dust from PICA, NuSil was applied to the entire MSL heatshield, including the MEDLI plugs. NuSil is a space grade designation of the siloxane copolymer, primarily used to protect against atomic oxygen erosion in the Low Earth Orbit environment. Ground testing of PICA-NuSil (PICA-N) models all exhibited surface temperature jumps of the order of 200 K due to oxide scale formation and subsequent NuSil burn-off. It is therefore critical to include a model for the aerothermal response of the coating in ongoing code development and validation efforts.

Description: Methane is a potent greenhouse gas, but a complete accounting of global methane sources and sinks is still ongoing. Sediments beneath glaciers and ice sheets harbour carbon reserves that, under certain conditions, can be converted to methane. However, the formation and release of such methane is an unquantified component of the arctic methane budget. Lamarche-Gagnon et al. present direct measurements of dissolved methane in proglacial discharge from a land-terminating glacier of the Greenland Ice Sheet. This proglacial discharge was supersaturated with methane and had diffusive methane fluxes similar to other terrestrial rivers for the duration of the summer measurement period. Their results suggest that variability in proglacial discharge is associated with methane release from subglacial environments, implicating both the form and evolution of the subglacial hydrologic system as a newly discovered control in the arctic methane cycle.The study by Lamarche-Gagnon et al. is an important example of how the cryosphere can interact with the surrounding Earth system in unexpected and potentially significant ways. Characterizing the ability of subglacial sediments to convert and store methane and the ability of the subglacial hydrologic system to export this methane to the atmosphere, through both modeling and observational studies, are critical steps in improving our knowledge of the sources and sinks of arctic methane and better constraining their future changes.

Description: Magnetic reconnection in a quasiparallel bow shock is investigated with twodimensional local particleincell simulations. In the shock transition and downstream regions, large amplitude magnetic fluctuations exist, and abundant current sheets form. In some current sheets, reconnection occurs, and ionscale and electronscale magnetic islands are generated. In electronscale island regions, only electron outflow jets are observed, producing a quadrupolar outofplane magnetic field pattern, while in ionscale islands, both ions and electrons are involved and energized in reconnection. Normalized reconnection rates are obtained to be between around 0.1 to 0.2, and particle acceleration signatures are seen in distribution functions.

Description: No abstract available

Description: Kinetic structures of electron diffusion regions (EDRs) under finite guide fields in magnetotail reconnection are reported. The EDRs with guide fields 0.140.5 (in unit of the reconnecting component) are detected by the Magnetospheric Multiscale spacecraft. The key new features include the following: (1) cold inflowing electrons accelerated along the guide field and demagnetized at the magnetic field minimum while remaining a coherent population with a low perpendicular temperature, (2) wave fluctuations generating strong perpendicular electron flows followed by alternating parallel flows inside the reconnecting current sheet under an intermediate guide field, and (3) gyrophase bunched electrons with high parallel speeds leaving the Xline region. The normalized reconnection rates for the three EDRs range from 0.05 to 0.3. The measurements reveal that finite guide fields introduce new mechanisms to break the electron frozenin condition.

Description: NASA is investigating the potential of integrating acoustic liners into fan cases to reduce fan noise, while maintaining the fans aerodynamic performance. An experiment was conducted to quantify the aerodynamic impact of circumferentially grooved fan cases with integrated acoustic liners on a 1.5 pressure ratio turbofan rotor. In order to improve the ability to measure small performance changes, fan performance calculations were updated to include real gas effects including the effect of humidity. For all fan cases tested, the measured difference in fan isentropic efficiency was found to be less than the measurement repeatability for a torque-based efficiency calculation (approx. = 0.2%), however, an unintended tip clearance difference between configurations makes it difficult to determine if circumferentially grooved fan cases degraded fan performance. Fan exit turbulence measurements showed a 1.5% reduction in total turbulence intensity between hardwall and circumferentially grooved fan cases in the tip vortex region, which is attributed to a disruption in the formation of the tip leakage vortex. This decrease in fan exit turbulence could potentially lead to a 1-2dB reduction in broadband rotor-stator interaction noise. Reduced aerodynamic performance losses associated with over-the-rotor liners could enable further fan noise reduction.

Description: Nearly all proglacial water discharge from the present-day Greenland Ice Sheet is routed englacially via moulins. Identification of these moulins in high-resolution imagery is a frequent topic of study, but the processes controlling how and where moulins form, including on past ice sheets for which remote-sensing data are not available, remain poorly understood. Because moulins may reasonably compose approximately 10-15% of the englacial-subglacial hydrologic system, the evolution and shape of moulins can alter the timing of meltwater inputs to the bed. This evolution can impact both the form of the subglacial hydrologic system and the structure of associated geomorphological structures. Here, we develop a physical model of moulin formation and evolution to constrain the role of englacial processes in controlling the form and structure of the subglacial hydrologic system. Ice deformation within and around a moulin is both viscous and elastic, with the rate of turbulent and heat dissipation from water circulation in the moulin controlling both moulin wall melting and warming of the surrounding ice. We find moulin geometry is responsive to changes in these parameters over hours to days, indicating that diurnal and multi-day variations in surface melt can substantially alter the geometry of a moulin and the pressure-discharge relationship at the bed of the ice sheet. These results should be considered carefully when determining surface water inputs for subglacial hydrologic models. In the future, a parameter space study of these results will be combined with an analytic model to create a predictive, stochastic model of moulin and crevasse locations. This future model will be applicable to constraining the potential for surface-to-bed connections in regions where the exact ice-sheet surface morphology is not known, including ice sheets under future warming atmospheric conditions, and paleo ice sheets, where moulins created modern landforms.

Description: A full-scale isolated proprotor test is currently being conducted in the USAF National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-Foot Wind Tunnel at NASA Ames. The test article is a 3-bladed research rotor derived from the right-hand rotor of the AW609; this rotor was manufactured by Bell Helicopter under contract to NASA. In this paper, this research rotor is referred to as "699". The test, nearly completed, is an integral part of the initial checkout test of the newly developed Tiltrotor Test Rig (TTR), whose purpose is to test advanced, full-scale proprotors in the NFAC. Figure 1 shows the TTR/699 installed in the 40- by 80-Foot test section. The TTR rotor axis is horizontal and the rig rotates in yaw on the wind tunnel turntable for conversion (transition) and helicopter mode testing. To date, a substantial amount of wind tunnel test data has already been acquired. The completed operational conditions include hover, airplane mode (cruise, wind tunnel airspeed V=61 to 267 knots), and the helicopter and conversion conditions (with a comprehensive sweep of the TTR yaw angle ranging, to date, from 90-deg yaw helicopter mode to 30-deg yaw conversion mode, at varying airspeeds). This 699 proprotor performance and loads correlation study uses these newly acquired wind tunnel test data. This paper represents the third analytical study, coming after two earlier analytical studies on the TTR/699; that is, a 2018 paper on pre-test predictions of 699 performance and loads, Ref. 1, and an upcoming January 2019 paper on aeroelastic stability analysis of the TTR/699 installed in the 40- by 80-Foot Wind Tunnel, Ref. 2. Reference 8 will present an overview of the entire TTR/699 test program. For completeness, Ref. 3 addresses the development and initial testing of the TTR. Background information on the TTR effort at NASA Ames can be found at the Aeromechanics website: https://rotorcraft.arc.nasa.gov/Research/Facilities/ttr.html. To the authors' knowledge, the full-scale results presented in this paper are the first of their kind. A literature survey brought up several existing correlation studies, but these were either based on small-scale test data (for example, the studies performed by the University of Maryland) or full-scale aircraft flight test data (for example, flight tests conducted by Bell Helicopter). Separately, the 2009 NASA study involving the JVX rotor is relevant (see Ref.4). The JVX is closely similar to the 699 in size and aerodynamics, and is accordingly a good reference for performance calculations. In Ref. 1 (as mentioned above), pre-test reality checks of the current analytical model were made by comparing JVX and 699 predictions in hover and forward flight (airplane mode).

Description: Two full seven-equation turbulence models have been implemented into the FUN3D code to evaluate their ability to improve the computation of challenging flows encountered in aerospace propulsion, including mixing flows. These models are the SSG/LRR and Wilcox full second-moment Reynolds stress models. They solve equations for the six components of the Reynolds stress and a seventh equation for the mixing length. Two standard eddy viscosity models are also evaluated for comparison, the Spalart-Allmaras (SA) one-equation model and the Menter Shear Stress Transport (SST-V) two-equation turbulence model. Flow through an axisymmetric reference nozzle is examined at three flow conditions: subsonic unheated, subsonic heated, and near sonic unheated. Centerline profiles of velocity and turbulent kinetic energy and radial profiles of velocity, turbulent kinetic energy and turbulent stresses are examined. characteristics, no significant changes in the downstream flow behavior compared to the baseline case are observed. Furthermore, the total power consumed by the fans for different incoming flow conditions also remain marginally the same. It is hoped that the results, albeit obtained at very low speeds. would serve as a database for this technologically interesting flow field that has not been explored adequately before.

Description: We consider the formation of a potential drop over the Earth's polar cap during geomagnetically quiet daytime. The observed potential drop is primarily defined by the hydrogen, photoelectron, and polar rain fluxes ratios and depends strongly on the energy distribution of the photoelectron flux. Polar rain is an essential component of the model required for plasma quasineutrality. The potential distribution along the magnetic field line has two regions, with a small, gradual, potential drop of 3 to 4 volts and a potential jump. The value of the potential jump depends on the hydrogen ion to photoelectron flux ratio and is also controlled by polar rain electrons. With quasineutrality required at its upper boundary, the jump only occurs in the presence of polar rain and its location depends on the polar rain flux. Model predictions compare well with FAST (Fast Auroral SnapshoT) observations presented by Kitamura et al.(2012, https://doi.org/10.1029/2011JA017459).

Description: Heated ethane (C2H6) has been proposed as an alternative to inert gases for use as a motive fluid in the experimental simulation of rocket exhaust plumes. By adjusting stagnation temperature, the isentropic exponent of ethane can be tuned to approximate those produced by common rocket propellants including hydrogen, hypergols, alcohols, and hydrocarbons. As a result, ethane can be made to follow a nozzle expansion process which is nearly identical to realistic rocket engine flow fields. Additionally, its high auto-ignition temperature and resistance to condensation enable the testing of expansion ratios much larger than conventional inertgas testing. NASA SSC has performed quasi-one-dimensional analyses using the Chemical Equilibrium with Applications (CEA) code as a preliminary means to compare flow fields produced by non-reacting ethane to those of reacting combustion products. A LO2/LH2 rocket engine operating at a chamber pressure of 5.0 MPa and a mixture ratio of 6.1 was used as an example case to demonstrate ethanes efficacy as a simulant. Errors for key similarity parameters were compared to legacy cold-flow test methods. Additional errors induced by machining tolerances and chemical impurities were also examined. Results suggest that at a 3% geometric scale and ~500 K ethane stagnation temperature, an error of less than 2.5% throughout the flow field is realistically achievable along the dimensions of Mach number, Reynolds number, pressure ratio, and isentropic exponent. The development of an experimental test bed for validation of this configuration is currently underway.

Description: A 13.49-percent-thick, slotted, natural-laminar-flow airfoil, the S207, for a transport aircraft has been designed and analyzed theoretically. The two primary objectives of high maximum lift, insensitive to roughness, and low profile drag have been achieved. The drag-divergence Mach number is predicted to be greater than 0.70.

Description: The values of the key atmospheric turbulence parameters (structure constants) for temperature and water vapor, that is, C(exp 2)(sub T), and C(exp 2)(sub Q), are highly dependent upon the vertical height within the atmosphere thus making it necessary to specify profiles of these values along the atmospheric propagation path. The remote sensing method suggested and described in this work makes use of a rapidly integrating microwave profiling radiometer to capture profiles of temperature and humidity through the atmosphere. The integration times of currently available profiling radiometers are such that they are approaching the temporal intervals over which one can possibly make meaningful assessments of these key atmospheric parameters. These integration times, coupled with the boundary effects of the Earths surface are, however, unconventional for turbulence characterization; the classical Kolmogorov turbulence theory and related 2/3 law for structure functions prevalent in the inertial subrange are no longer appropriate. An alternative to this classical approach is derived from first principles to account for the nuances of turbulent mechanics met with using radiometer sensing, that is, the large-scale turbulence driven by the various possible boundary conditions within the buoyancy subrange. Analytical expressions connecting the measured structure functions to the corresponding structure parameters are obtained. The theory is then applied to an experimental scenario involving radiometric profile measurements of temperature and shows very good results.

Description: Since the early twentieth century, the amplitudes of tidal constituents in the Gulf of Maine and Bay of Fundy display clear secular trends that are among the largest anywhere observed for a regional body of water. The M2 amplitude at Eastport, Maine, increased at a rate of 14.1 1.2 cm per century until it temporarily dropped during 19801990, apparently in response to changes in the wider North Atlantic. Annual tidal analyses indicate M2 reached an alltime high amplitude last year (2018). Here we report new estimates of tides derived from nineteenth century waterlevel measurements found in the U.S. National Archives. Results from Eastport, Portland, and Pulpit Harbor (tied to Bar Harbor) do not follow the twentieth century trends and indicate that the Gulf of Maine tide changes commenced sometime in the late nineteenth or early twentieth centuries, coincident with a transition to modern rates of sealevel rise as observed at Boston and Portland. General agreement is that sea level rise alone is insufficient to cause the twentiethcentury tide changes. A role for ocean stratification is suggested by the longterm warming of Gulf of Maine waters; archival water temperatures at Boston, Portland, and Eastport show increases of 2 C since the 1880s. In addition, a changing seasonal dependence in M2 amplitudes is reflected in a changing seasonal dependence in water temperatures. The observations suggest that models seeking to reproduce Gulf of Maine tides must consider both sea level rise and longterm changes in stratification.

Description: NASA's ASPIRE (Advanced Supersonic Parachute Inflation Research Experiments) project was launched to investigate the supersonic deployment, inflation and aerodynamics of full-scale disk-gap-band (DGB) parachutes. Three flight tests (October 2017, March 2018 and July 2018) deployed and examined parachutes meant for the upcoming "Mars 2020" mission. Mars-relevant conditions were achieved by performing the tests at high altitudes over Earth on a sounding rocket platform, with the parachute deploying behind a slender body (roughly 1/6-th the diameter of the capsule that will use this parachute for descent at Mars). All three tests were successful and delivered valuable data and imagery on parachute deployment and performance. CFD simulations were used in designing the flight test, interpreting the flight data, and extrapolating the results obtained during the flight test to predict parachute behavior at Mars behind a blunt capsule. This presentation will provide a brief overview of the test program and flight test data, with emphasis on differences in parachute performance due to the leading body geometry.

Description: Aerodynamic assessment of icing effects on swept wings is an important component of a larger effort to improve three-dimensional icing simulation capabilities. An understanding of ice-shape geometric fidelity and Reynolds and Mach number effects on iced-wing aerodynamics is needed to guide the development and validation of ice-accretion simulation tools. To this end, wind-tunnel testing was carried out for 8.9% and 13.3% scale semispan wing models based upon the Common Research Model airplane configuration. Various levels of geometric fidelity of an artificial ice shape representing a realistic glaze-ice accretion on a swept wing were investigated. The highest fidelity artificial ice shape reproduced all of the three-dimensional features associated with the glaze ice accretion. The lowest fidelity artificial ice shapes were simple, spanwise-varying horn ice geometries intended to represent the maximum ice thickness on the wing upper surface. The results presented in this paper show that changes in Reynolds and Mach number have only a small effect on the iced-wing aerodynamics relative to the clean-wing configuration. Furthermore, the addition of grit roughness to some lower-fidelity artificial ice shapes resulted in favorable lift and pitching moment comparisons to the wing with the highest fidelity artificial ice shape. For the wing with simple horn ice shapes, the dependence of maximum lift coefficient on horn height and angle are generally consistent with the trends observed for similar experiments conducted on iced airfoils in past research. In terms of usable lift however, the horn height did have a significant effect even for lower horn angles. This could be an important finding since usable lift may be more indicative of the impending iced-swept wing stall and need for additional pitch control than maximum lift coefficient.

Description: No abstract available

Description: This paper describes properties and behavior of magnetic reconnection and flux transfer events (FTEs) on the dayside magnetopause using the global hybrid-Vlasov code Vlasiator. We investigate two simulation runs with and without a sunward (positive) B(sub x) component of the interplanetary magnetic field (IMF) when the IMF is southward. The runs are two-dimensional in real space in the noon-midnight meridional (polar) plane and three-dimensional in velocity space. Solar wind input parameters are identical in the two simulations with the exception that the IMF is purely southward in one but tilted 45 toward the Sun in the other. In the purely southward case (i.e., without B(sub x) the magnitude of the magnetosheath magnetic field component tangential to the magnetopause is larger than in the run with a sunward tilt. This is because the shock normal is perpendicular to the IMF at the equatorial plane, whereas in the other run the shock configuration is oblique and a smaller fraction of the total IMF strength is compressed at the shock crossing. Hence, the measured average and maximum reconnection rate are larger in the purely southward run. The run with tilted IMF also exhibits a north-south asymmetry in the tangential magnetic field caused by the different angle between the IMF and the bow shock normal north and south of the equator. Greater north-south asymmetries are seen in the FTE occurrence rate, size, and velocity as well; FTEs moving toward the Southern Hemisphere are larger in size and observed less frequently than FTEs in the Northern Hemisphere.

Description: Swept wings and control surfaces are common elements of modern aircraft, and it has been shown both experimentally and theoretically that laminar-to-turbulent transition of the three-dimensional boundary layer that develops over them is highly sensitive to surface roughness. Numerous studies have been conducted on the effect of discrete roughness elements or distributed roughness elements on swept flow transition, however so far limited computational effort has been dedicated to the study of transition over swept wings with randomly distributed micron-sized roughness. In the present work, we set up to reproduce the extensive experimental data base generated by Dagenhart et al for the infinite swept wing NLF(2)-0415. To this purpose, we perform scale-resolving simulations of flow transition over smooth and rough surfaces using a high-order space-time spectral-element Discontinuous-Galerkin solver. Different types of surface roughnesses are implemented by elastically deforming the original mesh. The study shows that the experimental results cannot be accounted for by a perfectly smooth wing and reveals a strong sensitivity of the transition process to the representation of the surface roughness. The crossflow patterns and transition location approach those measured for some of the surface profiles, however a correlation between the wavenumber spectrum of the surface, grid resolution and boundary layer stability is yet to be established.

Description: Paper describing the outreach activities at INGV.

Description: Published

Description: 529-535

Description: 2TM. Divulgazione Scientifica

Description: JCR Journal

Description: © The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in International Journal of Environmental Research and Public Health 15 (2018): 723, doi:10.3390/ijerph15040723.

Description: There has been a massive increase in recent years of the use of lead (Pb) isotopes in attempts to better understand sources and pathways of Pb in the environment and in man or experimental animals. Unfortunately, there have been many cases where the quality of the isotopic data, especially that obtained by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS), are questionable, resulting in questionable identification of potential sources, which, in turn, impacts study interpretation and conclusions. We present several cases where the isotopic data have compromised interpretation because of the use of only the major isotopes 208Pb/206Pb and 207Pb/206Pb, or their graphing in other combinations. We also present some examples comparing high precision data from thermal ionization (TIMS) or multi-collector plasma mass spectrometry (MC-ICP-MS) to illustrate the deficiency in the Q-ICP-MS data. In addition, we present cases where Pb isotopic ratios measured on Q-ICP-MS are virtually impossible for terrestrial samples. We also evaluate the Pb isotopic data for rat studies, which had concluded that Pb isotopic fractionation occurs between different organs and suggest that this notion of biological fractionation of Pb as an explanation for isotopic differences is not valid. Overall, the brief review of these case studies shows that Q-ICP-MS as commonly practiced is not a suitable technique for precise and accurate Pb isotopic analysis in the environment and health fields

Description: Author(s): Pavel A. Volkov and Sergej Moroz We consider the stability of nodal surfaces in fermionic band systems with respect to the Coulomb repulsion. It is shown that nodal surfaces at the Fermi level are gapped out at low temperatures due to emergent particle-hole orders. Energy dispersion of the nodal surface suppresses the instability t... [Phys. Rev. B 98, 241107(R)] Published Thu Dec 13, 2018

Description: Author(s): Xiancong Lu and D. Sénéchal We investigate parity-mixing superconductivity in the two-dimensional Hubbard model with Rashba spin-orbit coupling, using cellular dynamical mean-field theory (CDMFT). A superconducting state with mixed singlet d -wave and triplet p -wave character is found in a wide range of doping. The singlet comp... [Phys. Rev. B 98, 245118] Published Thu Dec 13, 2018

Description: Author(s): Alireza Habibi, S. A. Jafari, and S. Rouhani We elucidate the reduction of the winding number caused by the on-site disorder in a next-nearest-neighbor XY model. When disorder becomes strong enough, Majorana edge modes become critically extended, beyond which they collapse into Anderson localized (AL) states in the bulk, resulting in a topolog... [Phys. Rev. B 98, 035142] Published Thu Jul 26, 2018

Description: Author(s): Carsten A. Ullrich To describe noncollinear magnetism in systems such as spiral ferromagnets or spin-frustrated molecules, density-functional methods need to give a proper account of the interplay between broken spin symmetries and exchange-correlation many-body effects. Here, the author develops a class of orbital-dependent exchange-correlation functionals for systems with noncollinear spin, treating correlation via a self-consistent scheme inspired by the Singwi-Tosi-Land-Sjölander method. The approach is applied to a very simple yet nontrivial benchmark system, the asymmetric half-filled Hubbard dimer, and is found to perform well, particularly in the weakly to moderately correlated regime. [Phys. Rev. B 98, 035140] Published Thu Jul 26, 2018

Description: Author(s): Kai Luo, Valentin V. Karasiev, and S. B. Trickey A simple, unconventional, nonempirical, constraint-based orbital-free generalized gradient approximation (GGA) noninteracting kinetic energy density functional is presented along with illustrative applications. The innovation is adaptation of constraint-based construction to the essential properties... [Phys. Rev. B 98, 041111(R)] Published Thu Jul 26, 2018

Description: Author(s): Dino Novko The unusual Raman spectrum of MgB 2 and its formidable temperature dependence are successfully reproduced by means of a parameter-free ab initio nonadiabatic theory that accounts for the electron-hole pair scattering mechanisms with the system phonons. This example turns out to be a prototypical case... [Phys. Rev. B 98, 041112(R)] Published Thu Jul 26, 2018

Description: Author(s): W. H. Brito, S. Choi, Y. X. Yao, and G. Kotliar We investigate the normal state of the superconducting compound PuCoGa 5 using the combination of density functional theory (DFT) and dynamical mean-field theory (DMFT), with the continuous time quantum Monte Carlo (CTQMC) and the vertex-corrected one-crossing approximation (OCA) as the impurity solv... [Phys. Rev. B 98, 035143] Published Fri Jul 27, 2018

Description: Author(s): Yi-Yan Wang (王义炎), Lin-Lin Sun (孙琳琳), Sheng Xu (徐升), Yuan Su (苏园), and Tian-Long Xia (夏天龙) We report the magnetotransport properties of HoSb, a semimetal with antiferromagnetic ground state. HoSb shows extremely large magnetoresistance (XMR) and Shubnikov-de Haas (SdH) oscillation at low temperature and high magnetic field. Different from previous reports in other rare earth monopnictides... [Phys. Rev. B 98, 045137] Published Fri Jul 27, 2018

Description: Author(s): Irakli Titvinidze, Max E. Sorantin, Antonius Dorda, Wolfgang von der Linden, and Enrico Arrigoni We address the steady-state behavior of a system consisting of several correlated monoatomic layers sandwiched between two metallic leads under the influence of a bias voltage. In particular, we investigate the interplay of the local Hubbard and the long-range Coulomb interaction on the charge redis... [Phys. Rev. B 98, 035146] Published Fri Jul 27, 2018

Description: Author(s): Akitoshi Nakano, Takumi Hasegawa, Shinya Tamura, Naoyuki Katayama, Satoshi Tsutsui, and Hiroshi Sawa Ta 2 NiSe 5 is considered a promising excitonic insulator (EI) candidate, in which the EI state is due to Coulomb interaction between electrons and holes. In Ta 2 NiSe 5 , the role of phonons is significant since the EI transition is accompanied by an orthorhombic-to-monoclinic structural transition at T s = ... [Phys. Rev. B 98, 045139] Published Mon Jul 30, 2018

Description: Author(s): F. C. Chen, X. Luo, J. Yan, Y. Sun, H. Y. Lv, W. J. Lu, C. Y. Xi, P. Tong, Z. G. Sheng, X. B. Zhu, W. H. Song, and Y. P. Sun Topological Weyl semimetals (WSMs), a new quantum state of matter, provide the realization of relativistic Weyl fermions in solid-state physics. The appearance of the Weyl nodes will demonstrate novel transport phenomena related to the chiral anomaly. Theoretical prediction hints that the giant plan... [Phys. Rev. B 98, 041114(R)] Published Mon Jul 30, 2018

Description: Author(s): M. Naseska, A. Pogrebna, G. Cao, Z. A. Xu, D. Mihailovic, and T. Mertelj We report on a systematic excitation-density-dependent all-optical femtosecond time-resolved study of the spin density wave state in iron-based superconductors. The destruction and recovery dynamics are measured by means of the standard and a multipulse pump-probe technique. The experimental data ar... [Phys. Rev. B 98, 035148] Published Mon Jul 30, 2018

Description: Author(s): Rui-Qi Xing, Laura Classen, and Andrey V. Chubukov We study the structure of the orbital order Γ = d x z † d x z − d y z † d y z in FeSe in light of recent scanning tunneling microscopy and angle-resolved photoemission spectroscopy (ARPES) data, which detect the shapes of the hole and electron pockets in the nematic phase. The geometry of the pockets indicates that... [Phys. Rev. B 98, 041108(R)] Published Tue Jul 24, 2018

Description: Author(s): A. Amaricci, A. Valli, G. Sangiovanni, B. Trauzettel, and M. Capone We investigate the emergence of antiferromagnetic ordering and its effect on the helical edge states in a quantum spin Hall insulator, in the presence of strong Coulomb interaction. Using dynamical mean-field theory, we show that the breakdown of lattice translational symmetry favors the formation o... [Phys. Rev. B 98, 045133] Published Tue Jul 24, 2018

Description: Author(s): Peng-Jie Guo, Huan-Cheng Yang, Kai Liu, and Zhong-Yi Lu As a type of fermions without counterpart in high energy physics, triply degenerate fermions show exotic physical properties, which are represented by triply degenerate nodal points in topological semimetals. Here, based on the space group theory analysis, we propose a practical guidance for seeking... [Phys. Rev. B 98, 045134] Published Tue Jul 24, 2018

Description: Author(s): Shiang Fang, Stephen Carr, Miguel A. Cazalilla, and Efthimios Kaxiras We derive electronic tight-binding Hamiltonians for strained graphene, hexagonal boron nitride, and transition-metal dichalcogenides based on Wannier transformation of ab initio density functional theory calculations. Our microscopic models include strain effects to leading order that respect the he... [Phys. Rev. B 98, 075106] Published Mon Aug 06, 2018

Description: Author(s): Vojtěch Vlček, Wenfei Li, Roi Baer, Eran Rabani, and Daniel Neuhauser We introduce the concept of sparse stochastic compression, an efficient stochastic sampling of any general function. The technique uses sparse stochastic orbitals (SSOs), short vectors that sample a small number of space points. As a first demonstration, SSOs are applied in conjunction with simple d... [Phys. Rev. B 98, 075107] Published Mon Aug 06, 2018

Description: Author(s): Daniel Kidd, A. S. Umar, and Kálmán Varga An iterative optimization approach that simultaneously minimizes the energy and optimizes the Lagrange multipliers enforcing desired constraints is presented. The method is tested on previously established benchmark systems and it is proved to be efficient and accurate. The approach can also be effi... [Phys. Rev. B 98, 075108] Published Mon Aug 06, 2018

Description: Author(s): Alex Thomson, Shubhayu Chatterjee, Subir Sachdev, and Mathias S. Scheurer We present the electronic band structures of states with the same symmetry as the three-sublattice planar antiferromagnetic order of the triangular lattice. Such states can also be defined on the honeycomb lattice provided the spin density waves lie on the bonds. We identify cases which are consiste... [Phys. Rev. B 98, 075109] Published Mon Aug 06, 2018

Description: Author(s): Andrzej Biborski, Andrzej P. Kądzielawa, and Józef Spałek We discuss electronic properties and their evolution for the linear chain of H 2 molecules in the presence of a uniform external force f acting along the chain. The system is described by an extended Hubbard model within a fully microscopic approach . Explicitly, the microscopic parameters describing ... [Phys. Rev. B 98, 085112] Published Tue Aug 07, 2018

Description: Author(s): Scott McKechnie, Jarvist M. Frost, Dimitar Pashov, Pooya Azarhoosh, Aron Walsh, and Mark van Schilfgaarde Metal halide perovskites exhibit a materials physics that is distinct from traditional semiconductors. While materials such as CH 3 NH 3 PbI 3 are nonmagnetic, the presence of heavy elements (Pb and I) in a noncentrosymmetric crystal environment result in a spin splitting of the frontier electronic bands... [Phys. Rev. B 98, 085108] Published Mon Aug 06, 2018

Description: Author(s): Klaus Halterman, Mohammad Alidoust, and Alexander Zyuzin We theoretically study the electromagnetic response of type-I and type-II centrosymmetric Weyl metals. We derive an anisotropic permittivity tensor with off-diagonal elements to describe such gyrotropic media. Our findings reveal that for appropriate Weyl cones tilts, the real part of the transverse... [Phys. Rev. B 98, 085109] Published Mon Aug 06, 2018

Description: Author(s): Ke Yang, D. I. Khomskii, and Hua Wu While double perovskites A 2 B B ′ O 6 , if ordered, usually form a rock-salt–type structure with a checkerboard B − B ′ ordering, it is surprising that Ca 2 FeMnO 6 has alternate FeO 2 and MnO 2 layers in its perovskite structure. Here, by using density functional calculations, we demonstrate that this unusual la... [Phys. Rev. B 98, 085105] Published Mon Aug 06, 2018

Description: Author(s): SangEun Han and Eun-Gook Moon Topological states may be protected by a lattice symmetry in a class of topological semimetals. In three spatial dimensions, the Berry flux around gapless excitations in momentum space concretely defines a chirality, so a protecting symmetry may be referred to as a chiral symmetry. Prime examples in... [Phys. Rev. B 97, 241101(R)] Published Mon Jun 04, 2018

Description: Author(s): Duk Y. Kim, Shi-Zeng Lin, Franziska Weickert, P. F. S. Rosa, Eric D. Bauer, Filip Ronning, J. D. Thompson, and Roman Movshovich The thermal conductivity of heavy-fermion superconductor Ce 0.95 Nd 0.05 CoIn 5 was measured with a magnetic field rotating in the tetragonal a − b plane. The thermal conductivity exhibits a step within the high-field low-temperature (HFLT) phase, which exists above 8 Tesla within the superconducting state... [Phys. Rev. B 97, 245120] Published Wed Jun 13, 2018

Description: Author(s): Julián Rincón, Elbio Dagotto, and Adrian E. Feiguin We study the photoinduced breakdown of a two-orbital Mott insulator and resulting metallic state. Using time-dependent density matrix renormalization group, we scrutinize the real-time dynamics of the half-filled two-orbital Hubbard model interacting with a resonant radiation field pulse. The breakd... [Phys. Rev. B 97, 235104] Published Tue Jun 05, 2018

Description: Author(s): Yongping Du, Er-jun Kan, Hu Xu, Sergey Y. Savrasov, and Xiangang Wan A search for new topological quantum systems is challenging due to the requirement of nontrivial band connectivity that leads to protected surface states of electrons. Progress in this field was primarily due to a realization of a band inversion mechanism between even and odd parity states that was ... [Phys. Rev. B 97, 245104] Published Tue Jun 05, 2018

Description: Author(s): Zheng Zhu, Itamar Kimchi, D. N. Sheng, and Liang Fu We investigate the non-Abelian topological chiral spin-liquid phase in the two-dimensional Kitaev honeycomb model subject to a magnetic field. By combining density matrix renormalization group and exact diagonalization we study the energy spectra, entanglement, topological degeneracy, and expectatio... [Phys. Rev. B 97, 241110(R)] Published Fri Jun 15, 2018

Description: Author(s): Chunxiao Liu, Xiao Chen, and Leon Balents The Sachdev-Ye-Kitaev (SYK) model is a quantum-mechanical model of fermions interacting with q -body random couplings. For q = 2 , it describes free particles and is nonchaotic in the many-body sense, while for q 〉 2 it is strongly interacting and exhibits many-body chaos. In this work we study the ent... [Phys. Rev. B 97, 245126] Published Fri Jun 15, 2018

Description: Author(s): Takami Tohyama, Michiyasu Mori, and Shigetoshi Sota The ground state of the t − t ′ − J ladder with four legs favors a striped charge distribution for the parameters corresponding to hole-doped cuprate superconductors. We investigate the dynamical spin and charge structure factors of the model by using the dynamical density matrix renormalization group (D... [Phys. Rev. B 97, 235137] Published Thu Jun 21, 2018

Description: Author(s): Agnese Tagliavini, Stefan Hummel, Nils Wentzell, Sabine Andergassen, Alessandro Toschi, and Georg Rohringer We present here two alternative schemes designed to correct the high-frequency truncation errors in the numerical treatment of the Bethe-Salpeter equations. The schemes are applicable to all Bethe-Salpeter calculations with a local two-particle irreducible vertex, which is relevant, e.g., for the dy... [Phys. Rev. B 97, 235140] Published Fri Jun 22, 2018

Description: Author(s): Adam Smith, Johannes Knolle, Roderich Moessner, and Dmitry L. Kovrizhin We study quantum quenches in two-dimensional lattice gauge theories with fermions coupled to dynamical Z 2 gauge fields. Through the identification of an extensive set of conserved quantities, we propose a generic mechanism of charge localization in the absence of quenched disorder both in the Hamilt... [Phys. Rev. B 97, 245137] Published Fri Jun 22, 2018

Description: Author(s): Juan Rubio-Zuazo, Ashish Chainani, Munetaka Taguchi, Daniel Malterre, Aida Serrano, and German R. Castro We study the electronic structure of well-characterized epitaxial films of FeO (wustite), γ − Fe 2 O 3 (maghemite), and Fe 3 O 4 (magnetite) using hard x-ray photoelectron spectroscopy (HAXPES), x-ray absorption near-edge spectroscopy (XANES), and electron energy loss spectroscopy (EELS). We carry out HAXPE... [Phys. Rev. B 97, 235148] Published Wed Jun 27, 2018

Description: Author(s): N. Pouse, S. Jang, B. D. White, S. Ran, R. B. Adhikari, C. C. Almasan, and M. B. Maple We report electrical resistivity, magnetization, and specific heat measurements on the correlated electron system Ce 1 − x Sm x CoIn 5 ( 0 ≤ x ≤ 1 ). Superconductivity (SC) in the heavy-fermion compound CeCoIn 5 , which is suppressed with increasing Sm concentration x , and antiferromagnetic (AFM) order of SmCoIn 5 ,... [Phys. Rev. B 97, 235149] Published Thu Jun 28, 2018

Description: Author(s): J. P. L. Faye, M. N. Kiselev, P. Ram, B. Kumar, and D. Sénéchal The interplay between the Kondo effect and magnetic ordering driven by the Ruderman-Kittel-Kasuya-Yosida interaction is studied within the two-dimensional Hubbard-Kondo lattice model. In addition to the antiferromagnetic exchange interaction J ⊥ between the localized spins and the conduction electron... [Phys. Rev. B 97, 235151] Published Thu Jun 28, 2018

Description: Author(s): Hennadii Yerzhakov and Joseph Maciejko We study the effect of quenched disorder on the semimetal-superconductor quantum phase transition in a model of two-dimensional Dirac semimetal with N flavors of two-component Dirac fermions, using perturbative renormalization group methods at one-loop order in a double epsilon expansion. For N ≥ 2 we... [Phys. Rev. B 98, 195142] Published Fri Nov 30, 2018

Description: Author(s): I. Valmianski, P. Y. Wang, S. Wang, Juan Gabriel Ramirez, S. Guénon, and Ivan K. Schuller We report the existence of two competing mechanisms in the current-driven electrical breakdown of vanadium sesquioxide ( V 2 O 3 ) and vanadium dioxide ( V O 2 ) nanodevices. Our experiments and simulations show that the competition between a purely electronic (PE) mechanism and an electrothermal (ET) mechan... [Phys. Rev. B 98, 195144] Published Fri Nov 30, 2018

Description: Author(s): Sumit Mazumdar We present a valence transition model for electron- and hole-doped cuprates, within which there occurs a discrete jump in ionicity Cu 2 + → Cu 1 + in both families upon doping, at or near optimal doping in the conventionally prepared electron-doped compounds and at the pseudogap phase transition in the ho... [Phys. Rev. B 98, 205153] Published Fri Nov 30, 2018

Description: Author(s): Vedran Jovic, Roland J. Koch, Swarup K. Panda, Helmuth Berger, Philippe Bugnon, Arnaud Magrez, Kevin E. Smith, Silke Biermann, Chris Jozwiak, Aaron Bostwick, Eli Rotenberg, and Simon Moser The efficiency and stability of RuO 2 in electrocatalysis has made this material a subject of intense fundamental and industrial interest. The surface functionality is rooted in its electronic and magnetic properties, determined by a complex interplay of lattice-, spin-rotational, and time-reversal s... [Phys. Rev. B 98, 241101(R)] Published Mon Dec 03, 2018

Description: Author(s): Iman Mahyaeh and Eddy Ardonne In this paper, we generalized the Peschel-Emery line of the interacting transverse field Ising model to a model based on three-state clock variables. Along this line, the model has exactly degenerate ground states, which can be written as product states. In addition, we present operators that transf... [Phys. Rev. B 98, 245104] Published Mon Dec 03, 2018

Description: Author(s): V. Brouet, L. Serrier-Garcia, A. Louat, L. Fruchter, F. Bertran, P. Le Fèvre, J. Rault, A. Forget, and D. Colson In Sr 2 IrO 4 and Sr 3 Ir 2 O 7 , correlations, magnetism, and spin-orbit coupling compete on similar energy scales, creating a new context to study metal-insulator transitions (MIT). We use here angle-resolved photoemission to investigate the MIT as a function of hole and electron doping in Sr 3 Ir 2 O 7 , obtain... [Phys. Rev. B 98, 235101] Published Mon Dec 03, 2018

Description: Author(s): Thomas Mertz, Karim Zantout, and Roser Valentí We introduce the concept of self-energy dispersion as an error bound on local theories and apply it to the two-dimensional Hubbard model on the square lattice at half filling. Since the self-energy has no single-particle analog and is not directly measurable in experiments, its general behavior as a... [Phys. Rev. B 98, 235105] Published Mon Dec 03, 2018

Description: Author(s): P. Thunström, O. Gunnarsson, Sergio Ciuchi, and G. Rohringer The local two-particle Green’s function and its generalized susceptibility are central building blocks in state-of-the-art theoretical descriptions of strongly correlated many-electron systems. The unexpected discovery of singular points in the generalized susceptibility, resulting in divergences of the two-particle irreducible vertex function and in multivaluedness of the Luttinger-Ward functional, has therefore attracted considerable interest. Unfortunately, almost no analytical results for irreducible vertices are available for correlated electrons. Here, the authors fill this gap by presenting fully analytical expressions for all irreducible vertex function of a simple, yet prototypical, correlated model, the single-orbital Hubbard atom. This gives highly relevant insights into the energy dependence of these functions. [Phys. Rev. B 98, 235107] Published Mon Dec 03, 2018

Description: Author(s): Sander H. Kooi, Guido van Miert, and Carmine Ortix We prove the existence of higher-order topological insulators with protected chiral hinge modes in quasi-two-dimensional systems made out of coupled layers stacked in an inversion-symmetric manner. In particular, we show that a homogeneous external magnetic field slightly tilted away from the stacki... [Phys. Rev. B 98, 245102] Published Mon Dec 03, 2018

Description: Author(s): Jörn W. F. Venderbos and Rafael M. Fernandes The recent observation of superconductivity in proximity to an insulating phase in twisted bilayer graphene (TBG) at small “magic” twist angles has been linked to the existence of nearly flat bands, which make TBG a fresh playground to investigate the interplay between correlations and superconducti... [Phys. Rev. B 98, 245103] Published Mon Dec 03, 2018