ALBERT

Beschreibung: Author(s): Ingo Barth and Olga Smirnova [Phys. Rev. A 84, 063415] Published Fri Dec 16, 2011

Beschreibung: Author(s): Ingo Barth and Olga Smirnova We show that ionization of noble gas atoms by a strong infrared circularly polarized laser field under standard experimental conditions can yield electrons with up to 100% spin polarization in energy-resolved measurements. Spin polarization arises due to the interplay of the electron-core entangleme... [Phys. Rev. A 88, 013401] Published Mon Jul 01, 2013

Beschreibung: Author(s): Kunlong Liu and Ingo Barth We derive the analytical formula of the ratio of the ionization rates of degenerate valence π ± orbitals of prealigned linear molecules in strong circularly polarized (CP) laser fields. Interestingly, our theory shows that the ionization ratio for molecular orbitals with opposite azimuthal quantum nu… [Phys. Rev. A 94, 043402] Published Mon Oct 03, 2016

Beschreibung: Author(s): Kunlong Liu, Klaus Renziehausen, and Ingo Barth The ionization of the prealigned nitric oxide molecule by strong circularly polarized laser fields is studied via theoretical simulations of the spin-resolved photoelectron momentum distributions by solving numerically the three-dimensional time-dependent Schrödinger equation. Due to the spin-orbit … [Phys. Rev. A 95, 063410] Published Tue Jun 13, 2017

Beschreibung: Author(s): Ingo Barth and Olga Smirnova We provide detailed analysis of strong field ionization of degenerate valence p orbitals by circularly polarized fields. Our analytical approach is conceptually equivalent to the Perelomov, Popov, and Terent'ev (PPT) theory and is virtually exact for short-range potentials. After benchmarking our re... [Phys. Rev. A 87, 013433] Published Thu Jan 31, 2013

Beschreibung: Author(s): Ingo Barth and Olga Smirnova We compare results of the recent experiment by Herath et al. [ T. Herath, L. Yan, S. K. Lee and W. Li Phys. Rev. Lett. 109 043004 (2012) ] on strong-field nonadiabatic tunneling in circularly polarized laser fields with the original predictions of our theory [ I. Barth and O. Smirnova Phys. Rev. A ... [Phys. Rev. A 87, 065401] Published Mon Jun 17, 2013

Beschreibung: Author(s): I. Barth and L. Friedland The two-photon ladder climbing (successive two-photon Landau-Zener-type transitions) in a chirped quantum nonlinear oscillator and its classical limit (subharmonic autoresonance) are discussed. An isomorphism between the chirped one- and two-photon resonances in the system is used in calculating the... [Phys. Rev. A 87, 053420] Published Fri May 31, 2013

Beschreibung: Author(s): Xiaofan Zhang, Liang Li, Xiaosong Zhu, Kunlong Liu, Xi Liu, Dian Wang, Pengfei Lan, Ingo Barth, and Peixiang Lu We demonstrate a scheme to produce coherent extreme ultraviolet and soft x-ray radiation with subpetahertz temporal helicity modulation, based on the high harmonic generation from current-carrying orbitals driven by intense linearly polarized laser fields. It is found that the electronic angular mom... [Phys. Rev. A 98, 023418] Published Mon Aug 20, 2018

Beschreibung: The Hubble Space Telescope (HST) was launched into low Earth orbit on April 24,1990. During the first servicing mission in December 1993 (3.6 years after launch), multilayer insulation (MLI) blankets were retrieved from the two magnetic sensing systems located on the light shield. Retrieval of one of the solar arrays during this mission also provided MLI blanket material from the solar array drive arm. These MLI materials were analyzed in ground-based facilities, and results indicate that the space-facing outer layer of the MLI, aluminized Teflon FEP (DuPont; fluorinated ethylene propylene), was beginning to degrade. Close inspection of the FEP revealed through-the-thickness cracks in areas with the highest solar exposure and stress concentration. During the second servicing mission in February 1997 (6.8 years after launch), astronauts observed and documented severe cracking in the outer layer of the MLI blankets on both the solar-facing and anti-solar-facing surfaces. During this second mission, some material from the outer layer of the light shield MLI was retrieved and subsequently analyzed in ground-based facilities. After the second servicing mission, a Failure Review Board was convened by NASA Goddard Space Flight Center to address the MLI degradation problem on HST. Members of the Electro-Physics Branch of the NASA Glenn Research Center at Lewis Field participated on this board. To determine possible degradation mechanisms, board researchers needed to consider all environmental constituents to which the FEP MLI surfaces were exposed. On the basis of measurements, models, and predictions, environmental exposure conditions for FEP surfaces on HST were estimated for various time periods from launch in 1990 through 2010, the planned end-of-life for HST. The table summarizes these data including the number and temperature ranges of thermal cycles; equivalent Sun hours; fluence and absorbed radiation dose from solar event x rays; fluence and absorbed dose from solar wind protons and electrons trapped in Earth s magnetic field; fluence of plasma electrons and protons; and atomic oxygen fluence.

Beschreibung: This viewgraph presentation attempts to develop a model of factors which need to be considered in the design and construction of spacecraft to lessen the effects of space weather on these vehicles. Topics considered include: space environments and effects, radiation environments and effects, space weather drivers, space weather models, climate models, solar proton activity and mission design for the GOES mission. The authors conclude that space environment models need to address issues from mission planning through operations and a program to develop and validate authoritative space environment models for application to spacecraft design does not exist at this time.