ALBERT

Description: A precision measurement of jet cross sections in neutral current deep-inelastic scattering for photon virtualities $$5.5

Description: The strong coupling constant $$alpha _mathrm{s}$$ α s is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of $$alpha _mathrm{s} (m_mathrm{Z})$$ α s ( m Z ) at the Z-boson mass $$m_Z$$ m Z are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be $$alpha _mathrm{s} (m_mathrm{Z}) =0.1157,(20)_mathrm{exp},(29)_mathrm{th}$$ α s ( m Z ) = 0.1157 ( 20 ) exp ( 29 ) th . Complementary, $$alpha _mathrm{s} (m_mathrm{Z})$$ α s ( m Z ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value $$alpha _mathrm{s} (m_mathrm{Z}) =0.1142,(28)_mathrm{tot}$$ α s ( m Z ) = 0.1142 ( 28 ) tot obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations.

Description: A Higgs field of particle physics can play the role of the inflaton in the early universe if it is non-minimally coupled to gravity. The Higgs inflation scenario predicts a small tensor to scalar ratio: \(r\simeq 0.003\) . Although this value is consistent with the upper bound \(r〈0.12\) given by the BICEP2/ Keck Array and Planck data, it is not at their maximum likelihood point: \(r\simeq 0.05\) . Inflationary observables depend not only on the inflationary models, but they also depend on the initial conditions of inflation. Changing the initial state of inflation can improve the value of r . In this work, we study the Higgs inflation model under general initial conditions and show that there is a subset of these general initial conditions which leads to enhancement of r . Then we show that this region of parameter space is consistent with a non-Gaussianity bound.

Description: When Morris and Thorne first proposed that traversable wormholes may be actual physical objects, they concentrated on the geometry by specifying the shape and redshift functions. This mathematical approach necessarily raises questions regarding the determination of the required stress-energy tensor. This paper discusses a natural way to obtain a complete wormhole solution by assuming that the wormhole (1) is supported by generalized Chaplygin gas and (2) admits conformal Killing vectors.

Description: In this article, we study the charmed baryon states \(\Lambda _c(2625)\) and \(\Xi _c(2815)\) with the spin-parity \({3\over 2}^-\) by subtracting the contributions from the corresponding charmed baryon states with the spin-parity \({3\over 2}^+\) using the QCD sum rules, and suggest a formula \( \mu =\sqrt{M_{\Lambda _c/\Xi _c}^2-{\mathbb {M}}_c^2}\) with the effective mass \({\mathbb {M}}_c=1.8\,\mathrm {GeV}\) to determine the energy scales of the QCD spectral densities, and make reasonable predictions for the masses and pole residues. The numerical results indicate that the \(\Lambda _c(2625)\) and \(\Xi _c(2815)\) have at least two remarkable under-structures.

Description: We study the radiative leptonic \(B_c\rightarrow \gamma \ell {\bar{\nu }}\) decays in nonrelativistic QCD effective field theory, and we explore the contribution from a fast-moving photon. As a result, interactions between the photon and the heavy quarks can be integrated out, resulting in the factorization formula for the decay amplitude. We calculate not only the relevant short-distance coefficients at leading order and next-to-leading order in \(\alpha _s\) , but also the nonrelativistic corrections at the order \(|\mathrm {v}|^2\) in our analysis. We find that the QCD corrections can significantly decrease the branching ratio, and this is of great importance in extracting the long-distance operator matrix elements of \(B_c\) . For phenomenological application, we present our results for the photon energy, lepton energy and lepton-neutrino invariant mass distribution.

Description: We point out a weak side of the commonly used determination of scalar cosmological perturbations lying in the fact that their average values can be nonzero for some matter distributions. It is shown that introduction of the finite-range gravitational potential instead of the infinite-range one resolves this problem. The concrete illustrative density profile is investigated in detail in this connection.

Description: A consistent BPS formalism to study the existence of topological axially symmetric vortices in generalized versions of the Born–Infeld–Higgs electrodynamics is implemented. Such a generalization modifies the field dynamics via the introduction of three nonnegative functions depending only in the Higgs field, namely, \(G(|\phi |)\) , \(w(|\phi |) \) , and \(V(|\phi |)\) . A set of first-order differential equations is attained when these functions satisfy a constraint related to the Ampère law. Such a constraint allows one to minimize the system’s energy in such way that it becomes proportional to the magnetic flux. Our results provides an enhancement of the role of topological vortex solutions in Born–Infeld–Higgs electrodynamics. Finally, we analyze a set of models entailing the recovery of a generalized version of Maxwell–Higgs electrodynamics in a certain limit of the theory.

Description: I put forward a qualitatively new dynamical mechanism for solving the electroweak hierarchy problem that does not require new physics at the electroweak scale. I argue that the infrared fluctuations of the gravitational field may provide a partial screening of the Higgs mass, similar to the infrared screening of the electric charge in quantum electrodynamics.

Description: It is thought that the spacetime geometry around black hole candidates is described by the Kerr solution, but an observational confirmation is still missing. Today, the continuum-fitting method and the analysis of the iron K \(\alpha \) line cannot unambiguously test the Kerr paradigm because of the degeneracy among the parameters of the system, in the sense that it is impossible with current X-ray data to distinguish a Kerr black hole from a non-Kerr object with different values of the model parameters. In this paper, we study the possibility of testing the Kerr nature of black hole candidates with X-ray spectropolarimetric measurements. Within our simplified model that does not include the effect of returning radiation, we find that it is impossible to test the Kerr metric and the problem is still the strong correlation between the spin and possible deviations from the Kerr geometry. Moreover, the correlation is very similar to that of the other two techniques, which makes the combination of different measurements not very helpful. Nevertheless, our results cannot be taken as conclusive and, in order to arrive at a final answer, the effect of returning radiation should be properly taken into account.

Description: We investigate unitarity within the complex-mass scheme, a convenient universal scheme for perturbative calculations involving unstable particles in quantum field theory which guarantees exact gauge invariance. Since this scheme requires one to introduce complex masses and complex couplings, the Cutkosky cutting rules, which express perturbative unitarity in theories of stable particles, are no longer valid. We derive corresponding rules for scalar theories with unstable particles based on Veltman’s largest-time equation and prove unitarity in this framework.

Description: We compute the decays \({B\rightarrow D^*_0}\) and \({B\rightarrow D^*_2}\) with finite masses for the b and c quarks. We first discuss the spectral properties of both the B meson as a function of its momentum and the \(D^*_0\) and \(D^*_2\) at rest. We compute the theoretical formulae leading to the decay amplitudes from the three-point and two-point correlators. We then compute the amplitudes at zero recoil of \({B\rightarrow D^*_0}\) , which turns out not to be vanishing contrary to what happens in the heavy quark limit. This opens the possibility to get better agreement with experiment. To improve the continuum limit we have added a set of data with smaller lattice spacing. The \({B\rightarrow D^*_2}\) vanishes at zero recoil and we show a convincing signal but only slightly more than 1 sigma from 0. In order to reach quantitatively significant results we plan to exploit fully smaller lattice spacings as well as another lattice regularisation.

Description: We present a simulation study of the prospects for the mass measurement of TeV-scale light-flavored right-handed squarks at a 3 TeV \(e^+e^-\) collider based on CLIC technology. In the considered model, these particles decay into their standard-model counterparts and the lightest neutralino, resulting in a signature of two jets plus missing energy. The analysis is based on full GEANT4 simulations of the CLIC_ILD detector concept, including Standard Model physics backgrounds and beam-induced hadronic backgrounds from two-photon processes. The analysis serves as a generic benchmark for the reconstruction of highly energetic jets in events with substantial missing energy. Several jet finding algorithms were evaluated, with the longitudinally invariant \(k_t\) algorithm showing a high degree of robustness towards beam-induced background while preserving the features typically found in algorithms developed for \(e^+e^-\) collisions. The presented study of the reconstruction of light-flavored squarks shows that for TeV-scale squark masses, sub-percent accuracy on the mass measurement can be achieved at CLIC.

Description: We evaluate the Hadamard function and the vacuum expectation value (VEV) of the current density for a charged scalar field, induced by flat boundaries in spacetimes with an arbitrary number of toroidally compactified spatial dimensions. The field operator obeys the Robin conditions on the boundaries and quasiperiodicity conditions with general phases along compact dimensions. In addition, the presence of a constant gauge field is assumed. The latter induces Aharonov–Bohm-type effect on the VEVs. There is a region in the space of the parameters in Robin boundary conditions where the vacuum state becomes unstable. The stability condition depends on the lengths of compact dimensions and is less restrictive than that for background with trivial topology. The vacuum current density is a periodic function of the magnetic flux, enclosed by compact dimensions, with the period equal to the flux quantum. It is explicitly decomposed into the boundary-free and boundary-induced contributions. In sharp contrast to the VEVs of the field squared and the energy-momentum tensor, the current density does not contain surface divergences. Moreover, for Dirichlet condition it vanishes on the boundaries. The normal derivative of the current density on the boundaries vanish for both Dirichlet and Neumann conditions and is nonzero for general Robin conditions. When the separation between the plates is smaller than other length scales, the behavior of the current density is essentially different for non-Neumann and Neumann boundary conditions. In the former case, the total current density in the region between the plates tends to zero. For Neumann boundary condition on both plates, the current density is dominated by the interference part and is inversely proportional to the separation.

Description: A small tensor-to-scalar ratio r may lead to distinctive phenomenology of high-scale supersymmetry. Assuming the same origin of SUSY breaking between the inflation and visible sector, we show model independent features. The simplest hybrid inflation, together with a new linear term for the inflaton field which is induced by a large gravitino mass, is shown to be consistent with all experimental data for r of order \(10^{-5}\) . For superpartner masses far above the weak scale we find that the reheating temperature after inflation might be below the value required by thermal leptogenesis if the inflaton decays to its products perturbatively, but above it if the decay is non-perturbatively instead. Remarkably, the gravitino overproduction can be evaded in such high-scale supersymmetry because of the kinematically blocking effect.

Description: We show how leading radiative corrections can be implemented in the general description of \(h\rightarrow 4\ell \) decays by means of pseudo observables (PO). With the inclusion of such corrections, the PO description of \(h\rightarrow 4\ell \) decays can be matched to next-to-leading-order electroweak calculations both within and beyond the Standard Model (SM). In particular, we demonstrate that with the inclusion of such corrections the complete next-to-leading-order SM prediction for the \(h\rightarrow 2e2\mu \) dilepton mass spectrum is recovered within \(1\,\%\) accuracy. The impact of radiative corrections for non-standard PO is also briefly discussed.

Description: A comprehensive review of physics at an \(e^+e^-\) linear collider in the energy range of \(\sqrt{s}=92\)  GeV–3 TeV is presented in view of recent and expected LHC results, experiments from low-energy as well as astroparticle physics. The report focusses in particular on Higgs-boson, top-quark and electroweak precision physics, but also discusses several models of beyond the standard model physics such as supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analysed as well.

Description: We investigate the fragmentation instability of hairy black holes in the theory with a Gauss–Bonnet (GB) term in asymptotically flat spacetime. Our approach is through the non-perturbative fragmentation instability. By this approach, we investigate whether the initial black hole can be broken into two black holes by comparing the entropy of the initial black hole with the sum of those of two fragmented black holes. The relation between the black hole instability and the GB coupling with dilaton hair are presented. We describe the phase diagrams with respect to the mass of the black hole solutions and coupling constants. We find that a perturbatively stable black hole can be unstable under fragmentation.

Description: A pulse-shape discrimination method based on artificial neural networks was applied to pulses simulated for different background, signal and signal-like interactions inside a germanium detector. The simulated pulses were used to investigate variations of efficiencies as a function of used training set. It is verified that neural networks are well-suited to identify background pulses in true-coaxial high-purity germanium detectors. The systematic uncertainty on the signal recognition efficiency derived using signal-like evaluation samples from calibration measurements is estimated to be 5 %. This uncertainty is due to differences between signal and calibration samples.

Description: In this article, we calculate the form factors and the coupling constant of the vertex \(D_{s}^{*}D_{s}\phi \) using the three-point QCD sum rules. We consider the contributions of the vacuum condensates up to dimension 7 in the operator product expansion. And all possible off-shell cases are considered, \(\phi \) , \(D_{s}\) and \(D_{s}^{*}\) , resulting in three different form factors. Then we fit the form factors into analytical functions and extrapolate them into time-like regions, which giving the coupling constant for the process. Our analysis indicates that the coupling constant for this vertex is \(G_{D_{s}^{*}D{_{s}}\phi }=4.12\pm 0.70\,\mathrm{GeV}^{-1}\) . The results of this work are very useful in the other phenomenological analysis. As an application, we calculate the coupling constant for the decay channel \(D_{s}^{*}\rightarrow D_{s}\gamma \) and analyze the width of this decay with the assumption of the vector meson dominance of the intermediate \(\phi (1020)\) . Our final result about the decay width of this decay channel is \(\Gamma =0.59\pm 0.15\,\mathrm{keV}\) .

Description: Extensive N -body simulations are among the key means for the study of numerous astrophysical and cosmological phenomena, so various schemes are developed for possibly higher accuracy computations. We demonstrate the principal possibility for revealing the evolution of a perturbed Hamiltonian system with an accuracy independent on time. The method is based on the Laplace transform and the derivation and analytical solution of an evolution equation in the phase space for the resolvent and using computer algebra.

Description: A search for a standard model Higgs boson produced in association with a top-quark pair and decaying to bottom quarks is presented. Events with hadronic jets and one or two oppositely charged leptons are selected from a data sample corresponding to an integrated luminosity of 19.5 \(\,\text {fb}^\text {-1}\) collected by the CMS experiment at the LHC in \(\mathrm {p}\mathrm {p}\) collisions at a centre-of-mass energy of 8 \(\,\hbox {TeV}\) . In order to separate the signal from the larger \(\hbox {t}\overline{\hbox {t}}\)  + jets background, this analysis uses a matrix element method that assigns a probability density value to each reconstructed event under signal or background hypotheses. The ratio between the two values is used in a maximum likelihood fit to extract the signal yield. The results are presented in terms of the measured signal strength modifier, \(\mu \) , relative to the standard model prediction for a Higgs boson mass of 125 \(\,\hbox {GeV}\) . The observed (expected) exclusion limit at a 95 % confidence level is \(\mu 〈4.2\) (3.3), corresponding to a best fit value \(\hat{\mu }=1.2^{+1.6}_{-1.5}\) .

Description: In this paper we are concerned with the effects of an anisotropic pressure on the boundary conditions of the anisotropic Lane–Emden equation and the homology theorem. Some new exact solutions of this equation are derived. Then some of the theorems governing the Newtonian perfect fluid star are extended, taking the anisotropic pressure into account.

Description: An optimized digital shaping filter has been developed for the Gerda experiment which searches for neutrinoless double beta decay in \(^{76}\) Ge. The Gerda Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) corresponding to 10 % at the \(Q\) value for \(0\nu \beta \beta \) decay in \(^{76}\) Ge is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping filter.

Description: A generalisation of the narrow-width approximation (NWA) is formulated which allows for a consistent treatment of interference effects between nearly mass-degenerate particles in the factorisation of a more complicated process into production and decay parts. It is demonstrated that interference effects of this kind arising in BSM models can be very large, leading to drastic modifications of predictions based on the standard NWA. The application of the generalised NWA is demonstrated both at tree level and at one-loop order for an example process where the neutral Higgs bosons h and H of the MSSM are produced in the decay of a heavy neutralino and subsequently decay into a fermion pair. The generalised NWA, based on on-shell matrix elements or their approximations leading to simple weight factors, is shown to produce UV- and IR-finite results which are numerically close to the result of the full process at tree level and at one-loop order, where an agreement of better than \(1\,\%\) is found for the considered process. The most accurate prediction for this process based on the generalised NWA, taking into account also corrections that are formally of higher orders, is briefly discussed.

Description: A new theory of gravity called Eddington-inspired Born–Infeld (EiBI) gravity was recently proposed by Bañados and Ferreira. This theory leads to some exciting new features, such as free of cosmological singularities. In this paper, we first obtain a charged EiBI black hole solution with a nonvanishing cosmological constant when the electromagnetic field is included in. Then based on it, we study the strong gravitational lensing by the asymptotic flat charged EiBI black hole. The strong deflection limit coefficients and observables are shown to closely depend on the additional coupling parameter \(\kappa \) in the EiBI gravity. It is found that, compared with the corresponding charged black hole in general relativity, the positive coupling parameter \(\kappa \) will shrink the black hole horizon and photon sphere. Moreover, the coupling parameter will decrease the angular position and relative magnitudes of the relativistic images, while increase the angular separation, which may shine new light on testing such gravity theory in near future by the astronomical instruments.

Description: This manuscript is devoted to the investigation of the Bianchi type I universe in the context of f ( R ,  T ) gravity. For this purpose, we explore the exact solutions of locally rotationally symmetric Bianchi type I spacetime. The modified field equations are solved by assuming an expansion scalar \(\theta \) proportional to the shear scalar \(\sigma \) , which gives \(A=B^n\) , where A ,   B are the metric coefficients and n is an arbitrary constant. In particular, three solutions have been found and physical quantities are calculated in each case.

Description: By detecting redshift drift in the spectra of the Lyman- \(\alpha \) forest of distant quasars, the Sandage–Loeb (SL) test directly measures the expansion of the universe, covering the “redshift desert” of \(2 \lesssim z \lesssim 5\) . Thus this method is definitely an important supplement to the other geometric measurements and will play a crucial role in cosmological constraints. In this paper, we quantify the ability of the SL test signal by a CODEX-like spectrograph for constraining interacting dark energy. Four typical interacting dark energy models are considered: (i) \(Q=\gamma H\rho _c\) , (ii) \(Q=\gamma H\rho _{de}\) , (iii) \(Q=\gamma H_0\rho _c\) , and (iv) \(Q=\gamma H_0\rho _{de}\) . The results show that for all the considered interacting dark energy models, relative to the current joint SN  \(+\)  BAO  \(+\)  CMB  \(+\)   \(H_0\) observations, the constraints on \(\Omega _m\) and \(H_0\) would be improved by about 60 and 30–40 %, while the constraints on w and \(\gamma \) would be slightly improved, with a 30-year observation of the SL test. We also explore the impact of the SL test on future joint geometric observations. In this analysis, we take the model with \(Q=\gamma H\rho _c\) as an example, and we simulate future SN and BAO data based on the space-based project WFIRST. We find that with the future geometric constraints, the redshift drift observations would help break the geometric degeneracies in a meaningful way, thus the measurement precisions of \(\Omega _m\) , \(H_0\) , w , and \(\gamma \) could be substantially improved using future probes.

Description: To identify the nature of the newly observed charged resonance \(Z_c(4200)^+\) , we study its hadronic decays \(Z_c(4200)^+\rightarrow J/\psi \pi ^+, Z_c(4200)^+\rightarrow \eta _c\rho ^+\) and \(Z_c(4200)^+\rightarrow D^+\bar{D}^{*0}\) as a charmonium-like tetraquark state. In the framework of the QCD sum rules, we calculate the three-point functions and extract the coupling constants and decay widths for these interaction vertices. Including all these channels, the full decay width of the \(Z_c(4200)^+\) state is consistent with the experimental value reported by the Belle Collaboration, supporting the tetraquark interpretation of this state.

Description: A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2012 at \(\sqrt{s}=8\)  TeV from pp collisions corresponding to an integrated luminosity of 20.3 fb \(^{-1}\) are examined. Particles producing anomalously high ionisation, consistent with long-lived massive particles with electric charges from \(|q|=2e\) to \(|q|=6e\) are searched for. No signal candidate events are observed, and 95 % confidence level cross-section upper limits are interpreted as lower mass limits for a Drell–Yan production model. The mass limits range between 660 and 785 GeV.

Description: We study to which extent SUSY extensions of the Standard Model can describe the excess of events of 3.0 standard deviations observed by ATLAS in the on- Z signal region, respecting constraints by CMS on similar signal channels as well as constraints from searches for jets and \(E^\mathrm{miss}_\text {T}\) . GMSB-like scenarios are typically in conflict with these constraints, and do not reproduce well the shape of the \(E^\mathrm{miss}_\text {T}\) distribution of the data. An alternative scenario with two massive neutralinos can improve fits to the total number of events as well as to the \(H_\text {T}\) and \(E^\mathrm{miss}_\text {T}\) distributions. Such a scenario can be realised within the NMSSM.

Description: Leading-twist operators have a remarkable property that their divergence vanishes in a free theory. Recently it was suggested that this property can be used for an alternative technique to calculate anomalous dimensions of leading-twist operators and allows one to gain one order in perturbation theory so that, i.e., two-loop anomalous dimensions can be calculated from one-loop Feynman diagrams, etc. In this work we study the feasibility of this program by a toy-model example of the \(\varphi ^3\) theory in six dimensions. Our conclusion is that this approach is valid, although it does not seem to present considerable technical simplifications as compared to the standard technique. It does provide one, however, with a very nontrivial check of the calculation as the structure of the contributions is very different.

Description: Recently, a family of interesting analytical brane solutions were found in f ( R ) gravity with \(f(R)=R \,+\, \alpha R^2\) in Bazeia et al. (Phys Lett B 729:127 2014 ). In these solutions, the inner brane structure can be turned on by tuning the value of the parameter \(\alpha \) . In this paper, we investigate how the parameter \(\alpha \) affects the localization and the quasilocalization of the tensorial gravitons around these solutions. It is found that, in a range of \(\alpha \) , despite the brane having an inner structure, there is no graviton resonance. However, in some other regions of the parameter space, although the brane has no internal structure, the effective potential for the graviton Kaluza–Klein (KK) modes has a singular structure, and there exist a series of graviton resonant modes. The contribution of the massive graviton KK modes to Newton’s law of gravity is discussed briefly.

Description: The production of the Standard Model Higgs boson in association with a vector boson, followed by the dominant decay to \(H \rightarrow b\bar{b}\) , is a strong prospect for confirming and measuring the coupling to b -quarks in pp collisions at \(\sqrt{s}=14\)  TeV. We present an updated study of the prospects for this analysis, focussing on the most sensitive highly Lorentz-boosted region. The evolution of the efficiency and composition of the signal and main background processes as a function of the transverse momentum of the vector boson are studied covering the region 200–1000 GeV, comparing both a conventional dijet and jet substructure selection. The lower transverse momentum region (200–400 GeV) is identified as the most sensitive region for the Standard Model search, with higher transverse momentum regions not improving the statistical sensitivity. For much of the studied region (200–600 GeV), a conventional dijet selection performs as well as the substructure approach, while for the highest transverse momentum regions ( \(〉\) 600 GeV), which are particularly interesting for Beyond the Standard Model and high luminosity measurements, the jet substructure techniques are essential.

Description: Massive QED, in contrast with its massless counterpart, possesses two conserved charges; one is a screened (vanishing) Maxwell charge which is directly associated with the massive vector mesons through the identically conserved Maxwell current, while the presence of a particle-antiparticle counting charge depends on the matter. A somewhat peculiar situation arises for couplings of Hermitian matter fields to massive vector potentials; in that case the only current is the screened Maxwell current and the coupling disappears in the massless limit. In the case of self-interacting massive vector mesons the situation becomes even more peculiar in that the usually renormalizability guaranteeing validity of the first order power-counting criterion breaks down in second order and requires the compensatory presence of additional Hermitian H -fields. Some aspect of these observation have already been noticed in the BRST gauge theoretic formulation, but here we use a new setting based on string-local vector mesons which is required by Hilbert space positivity (“off-shell unitarity”). This new formulation explains why spontaneous symmetry breaking cannot occur in the presence of higher spin \(s\ge 1\)  fields. The coupling to H -fields induces Mexican hat-like self-interactions; they are not imposed and bear no relation with spontaneous symmetry breaking; they are rather consequences of the foundational causal localization properties realized in a Hilbert space setting. In the case of self-interacting massive vector mesons their presence is required in order to maintain the first order power-counting restriction of renormalizability also in second order. The presentation of the new Hilbert space setting for vector mesons which replaces gauge theory and extends on-shell unitarity to its off-shell counterpart is the main motivation for this work. The new Hilbert space setting also shows that the second order Lie-algebra structure of self-interacting vector mesons is a consequence of the principles of QFT and promises a deeper understanding of the origin of confinement.

Description: We develop a methodology for the construction of a Hessian representation of Monte Carlo sets of parton distributions, based on the use of a subset of the Monte Carlo PDF replicas as an unbiased linear basis, and of a genetic algorithm for the determination of the optimal basis. We validate the methodology by first showing that it faithfully reproduces a native Monte Carlo PDF set (NNPDF3.0), and then, that if applied to Hessian PDF set (MMHT14) which was transformed into a Monte Carlo set, it gives back the starting PDFs with minimal information loss. We then show that, when applied to a large Monte Carlo PDF set obtained as combination of several underlying sets, the methodology leads to a Hessian representation in terms of a rather smaller set of parameters (MC-H PDFs), thereby providing an alternative implementation of the recently suggested Meta-PDF idea and a Hessian version of the recently suggested PDF compression algorithm (CMC-PDFs). The mc2hessian conversion code is made publicly available together with (through LHAPDF6 ) a Hessian representations of the NNPDF3.0 set, and the MC-H PDF set.

Description: We explore a fermionic dark matter model with a possible extension of Standard Model of particle physics into two Higgs doublet model. Higgs doublets couple to the singlet fermionic dark matter through a non-renormalisable coupling providing a new physics scale. We explore the viability of such dark matter candidate and constrain the model parameter space by collider serach, relic density of DM, direct detection measurements of DM-nucleon scattering cross-section and with the experimentally obtained results from indirect search of dark matter.

Description: An overview of the flavour problem is presented, with emphasis on the theoretical efforts to find a satisfactory description of the fermion masses and the mixing angles.

Description: The production of the massive bosons \(Z^0\) and \(W^{\pm }\) could provide an excellent tool to study cold nuclear matter effects and the modifications of nuclear parton distribution functions (nPDFs) relative to the parton distribution functions (PDFs) of a free proton in high-energy nuclear reactions at the LHC as well as in heavy-ion collisions (HIC) with much higher center-of-mass energies available in the future colliders. In this paper we calculate the rapidity and transverse momentum distributions of the vector boson and their nuclear modification factors in p + Pb collisions at \(\sqrt{s_{NN}}=63\)  TeV and in Pb + Pb collisions at \(\sqrt{s_{NN}}=39\)  TeV in the framework of perturbative QCD by utilizing three parametrization sets of nPDFs: EPS09, DSSZ, and nCTEQ. It is found that in heavy-ion collisions at such high colliding energies, both the rapidity distribution and the transverse momentum spectrum of vector bosons are considerably suppressed in wide kinematic regions with respect to p + p reactions due to large nuclear shadowing effect. We demonstrate that the massive vector boson production processes with sea quarks in the initial state may give more contributions than those with valence quarks in the initial state; therefore in future heavy-ion collisions the isospin effect is less pronounced and the charge asymmetry of the W boson will be reduced significantly as compared to that at the LHC. A large difference between results with nCTEQ and results with EPS09 and DSSZ is observed in nuclear modifications of both rapidity and \(p_T\) distributions of \(Z^0\) and W in the future HIC.

Description: We present a frequentist analysis of the parameter space of the pMSSM10, in which the following ten soft SUSY-breaking parameters are specified independently at the mean scalar top mass scale \(M_\mathrm{SUSY}\equiv \sqrt{m_{\tilde{t}_{1}} m_{\tilde{t}_{2}}}\) : the gaugino masses \(M_{1,2,3}\) , the first-and second-generation squark masses \(m_{\tilde{q}_1}= m_{\tilde{q}_2}\) , the third-generation squark mass \(m_{\tilde{q}_3}\) , a common slepton mass \(m_{\tilde{\ell }}\) and a common trilinear mixing parameter A , as well as the Higgs mixing parameter \(\mu \) , the pseudoscalar Higgs mass \(M_A\) and \(\tan \beta \) , the ratio of the two Higgs vacuum expectation values. We use the MultiNest sampling algorithm with \(\sim \) 1.2 \(\times 10^9\) points to sample the pMSSM10 parameter space. A dedicated study shows that the sensitivities to strongly interacting sparticle masses of ATLAS and CMS searches for jets, leptons \(+\) signals depend only weakly on many of the other pMSSM10 parameters. With the aid of the Atom and Scorpion codes, we also implement the LHC searches for electroweakly interacting sparticles and light stops, so as to confront the pMSSM10 parameter space with all relevant SUSY searches. In addition, our analysis includes Higgs mass and rate measurements using the HiggsSignals code, SUSY Higgs exclusion bounds, the measurements of \(\mathrm{BR}(B_s \rightarrow \mu ^+\mu ^-)\) by LHCb and CMS, other B -physics observables, electroweak precision observables, the cold dark matter density and the XENON100 and LUX searches for spin-independent dark matter scattering, assuming that the cold dark matter is mainly provided by the lightest neutralino \(\tilde{\chi }^0_{1}\) . We show that the pMSSM10 is able to provide a supersymmetric interpretation of \((g-2)_\mu \) , unlike the CMSSM, NUHM1 and NUHM2. As a result, we find (omitting Higgs rates) that the minimum \(\chi ^2 = 20.5\) with 18 degrees of freedom (d.o.f.) in the pMSSM10, corresponding to a \(\chi ^2\) probability of 30.8 %, to be compared with \(\chi ^2/\mathrm{d.o.f.} = 32.8/24 \ (31.1/23) \ (30.3/22)\) in the CMSSM (NUHM1) (NUHM2). We display the one-dimensional likelihood functions for sparticle masses, and we show that they may be significantly lighter in the pMSSM10 than in the other models, e.g., the gluino may be as light as \(\sim \) 1250 \(\,\, \mathrm {GeV}\) at the 68 % CL, and squarks, stops, electroweak gauginos and sleptons may be much lighter than in the CMSSM, NUHM1 and NUHM2. We discuss the discovery potential of future LHC runs, \(e^+e^-\) colliders and direct detection experiments.

Description: We compute the corrections to the Schwarzschild metric necessary to reproduce the Hawking temperature derived from a generalized uncertainty principle (GUP), so that the GUP deformation parameter is directly linked to the deformation of the metric. Using this modified Schwarzschild metric, we compute corrections to the standard general relativistic predictions for the light deflection and perihelion precession, both for planets in the solar system and for binary pulsars. This analysis allows us to set bounds for the GUP deformation parameter from well-known astronomical measurements.

Description: LHC searches for non-standard Higgs bosons decaying into tau lepton pairs constitute a sensitive experimental probe for physics beyond the Standard Model (BSM), such as supersymmetry (SUSY). Recently, the limits obtained from these searches have been presented by the CMS collaboration in a nearly model-independent fashion – as a narrow resonance model – based on the full \(8\,\, \mathrm {TeV}\) dataset. In addition to publishing a \(95~\%~\mathrm {C.L.}\) exclusion limit, the full likelihood information for the narrow resonance model has been released. This provides valuable information that can be incorporated into global BSM fits. We present a simple algorithm that maps an arbitrary model with multiple neutral Higgs bosons onto the narrow resonance model and derives the corresponding value for the exclusion likelihood from the CMS search. This procedure has been implemented into the public computer code HiggsBounds (version 4.2.0 and higher). We validate our implementation by cross-checking against the official CMS exclusion contours in three Higgs benchmark scenarios in the Minimal Supersymmetric Standard Model (MSSM), and find very good agreement. Going beyond validation, we discuss the combined constraints of the \(\tau \tau \) search and the rate measurements of the SM-like Higgs at \(125\,\, \mathrm {GeV}\) in a recently proposed MSSM benchmark scenario, where the lightest Higgs boson obtains SM-like couplings independently of the decoupling of the heavier Higgs states. Technical details for how to access the likelihood information within HiggsBounds are given in the appendix. The program is available at http://higgsbounds.hepforge.org .

Description: We investigate inflation within \(f(R,\phi )\) -theories, where a dynamical scalar field is coupled to gravity. A class of models which can support early-time acceleration with the emerging of an effective cosmological constant at high curvature is studied. The dynamics of the field allow for exit from inflation leading to the correct amount of inflation in agreement with cosmological data. Furthermore, the spectral index and tensor-to-scalar ratio of the models are carefully analyzed. A generalization of the theory to incorporate dark matter in the context of mimetic gravity, and further extensions of the latter, are also discussed.

Description: The existence of both a minimum mass and a minimum density in nature, in the presence of a positive cosmological constant, is one of the most intriguing results in classical general relativity. These results follow rigorously from the Buchdahl inequalities in four-dimensional de Sitter space. In this work, we obtain the generalized Buchdahl inequalities in arbitrary space–time dimensions with \(\Lambda \ne 0\) and consider both the de Sitter and the anti-de Sitter cases. The dependence on D , the number of space–time dimensions, of the minimum and maximum masses for stable spherical objects is explicitly obtained. The analysis is then extended to the case of dark energy satisfying an arbitrary linear barotropic equation of state. The Jeans instability of barotropic dark energy is also investigated, for arbitrary D , in the framework of a simple Newtonian model with and without viscous dissipation, and we determine the dispersion relation describing the dark energy–matter condensation process, along with estimates of the corresponding Jeans mass (and radius). Finally, the quantum mechanical implications of the mass limits are investigated, and we show that the existence of a minimum mass scale naturally leads to a model in which dark energy is composed of a ‘sea’ of quantum particles, each with an effective mass proportional to \(\Lambda ^{1/4}\) .

Description: We study multi-soliton solutions of the four-dimensional SU(N) Skyrme model by combining the hedgehog ansatz for SU(N) based on the harmonic maps of \(S^{2}\) into \(CP^{N-1}\) and a geometrical trick which allows to analyze explicitly finite-volume effects without breaking the relevant symmetries of the ansatz. The geometric set-up allows to introduce a parameter which is related to the ’t Hooft coupling of a suitable large N limit, in which \(N\rightarrow \infty \) and the curvature of the background metric approaches zero, in such a way that their product is constant. The relevance of such a parameter to the physics of the system is pointed out. In particular, we discuss how the discrete symmetries of the configurations depend on it.

Description: The effects of color reconnection (CR) at \({\mathrm e}^+{\mathrm e}^-\) colliders are revisited, with focus on recently developed CR models. The new models are compared with the LEP2 measurements for \({\mathrm e}^+{\mathrm e}^- \rightarrow {\mathrm W}^+{\mathrm W}^- \rightarrow {\mathrm q}_1 \overline{\mathrm q}_2 {\mathrm q}_3 \overline{\mathrm q}_4\) and found to lie within their limits. Prospects for constraints from new high-luminosity \({\mathrm e}^+{\mathrm e}^-\) colliders are discussed. The novel arena of CR in Higgs decays is introduced, and it is illustrated by shifts in angular correlations that would be used to set limits on a potential CP -odd admixture of the 125 GeV Higgs state.

Description: The Lorentz transformation properties of the equal-time bound-state Bethe–Salpeter amplitude in the two-dimensional massless quantum electrodynamics (the so-called Schwinger model) are considered. It is shown that while boosting a bound state (a ‘meson’) this amplitude is subject to approximate Lorentz contraction. The effect is exact for large separations of constituent particles (‘quarks’), while for small distances the deviation is more significant. For this phenomenon to appear, the full function, i.e. with the inclusion of all instanton contributions, has to be considered. The amplitude in each separate topological sector does not exhibit such properties.

Description: The canonical Aharonov–Bohm effect is usually studied with time-independent potentials. In this work, we investigate the Aharonov–Bohm phase acquired by a charged particle moving in time-dependent potentials. In particular, we focus on the case of a charged particle moving in the time-varying field of a plane electromagnetic wave. We work out the Aharonov–Bohm phase using both the potential (i.e. \(\oint A_\mu \mathrm{d}x ^\mu \) ) and the field (i.e. \(\frac{1}{2}\int F_{\mu \nu } \mathrm{d}\sigma ^{\mu \nu }\) ) forms of the Aharonov–Bohm phase. We give conditions in terms of the parameters of the system (frequency of the electromagnetic wave, the size of the space–time loop, amplitude of the electromagnetic wave) under which the time-varying Aharonov–Bohm effect could be observed.

Description: The LHC data on jet fragmentation function and jet shapes in PbPb collisions at center-of-mass energy 2.76 TeV per nucleon pair are analyzed and interpreted in the frameworks of PYthia QUENched (PYQUEN) jet quenching model. A specific modification of longitudinal and radial jet profiles in most central PbPb collisions as compared with pp data is close to that obtained with PYQUEN simulations, taking into account wide-angle radiative and collisional partonic energy losses. The contribution of radiative and collisional loss to the medium-modified intra-jet structure is estimated.

Description: When averages of different experimental determinations of the same quantity are computed, each with statistical and systematic error components, then frequently the statistical and systematic components of the combined error are quoted explicitly. These are important pieces of information since statistical errors scale differently and often more favorably with the sample size than most systematical or theoretical errors. In this communication we describe a transparent procedure by which the statistical and systematic error components of the combination uncertainty can be obtained. We develop a general method and derive a general formula for the case of Gaussian errors with or without correlations. The method can easily be applied to other error distributions, as well. For the case of two measurements, we also define disparity and misalignment angles, and discuss their relation to the combination weight factors.

Description: In this work, we have studied the accretion of the \((n+2)\) -dimensional charged BTZ black hole (BH). The critical point and square speed of sound have been obtained. The mass of the BTZ BH has been calculated and we have observed that the mass of the BTZ BH is related with the square root of the energy density of the dark energy which accretes onto the BH in our accelerating FRW universe. We have assumed modified Chaplygin gas (MCG) as a candidate of dark energy which accretes onto the BH and we have found the expression of BTZ BH mass. Since in our solution of MCG, this model generates only quintessence dark energy (not phantom) and so BTZ BH mass increases during the whole evolution of the accelerating universe. Next we have assumed five kinds of parametrizations of well-known dark-energy models. These models generate both quintessence and phantom scenarios i.e., phantom crossing models. So if these dark energies accrete onto the BTZ BH, then in the quintessence stage, the BH mass increases up to a certain value (finite value) and then decreases to a certain finite value for the phantom stage during the whole evolution of the universe. We have shown these results graphically.

Description: We consider lepton-flavour violating decays of the top quark, mediated by 4-fermion operators. We compile constraints on a complete set of SU(3)  \(\times \)  U(1)-invariant operators, arising from their loop contributions to rare decays and from HERA’s single-top search. The bounds on e – \(\mu \) flavour change are more restrictive than on \(\ell \) – \(\tau \) ; nonetheless the top could decay to a jet \({+} e \bar{\mu }\) with a branching ratio of order \(10^{-3}\) . We estimate that the currently available LHC data (20 fb \(^{-1}\) at 8 TeV) could be sensitive to \(BR(t \rightarrow e \bar{\mu }\) + jet) \( {\sim } 6\times 10^{-5}\) , and we extrapolate that 100 fb \(^{-1}\) at 13 TeV could reach a sensitivity of \({\sim } 1 \times 10^{-5}\) .

Description: We carry out ADM splitting in the Lagrangian formulation and establish a procedure in which (almost) all of the unphysical components of the metric are removed by using the 4D diffeomorphism and the measure-zero 3D symmetry. The procedure introduces a constraint that corresponds to the Hamiltonian constraint of the Hamiltonian formulation, and its solution implies that the 4D dynamics admits an effective description through 3D hypersurface physics. As far as we can see, our procedure implies potential renormalizability of the ADM formulation of 4D Einstein gravity for which a complete gauge-fixing in the ADM formulation and hypersurface foliation of geometry are the key elements. If true, this implies that the alleged unrenormalizability of 4D Einstein gravity may be due to the presence of the unphysical fields. The procedure can straightforwardly be applied to quantization around a flat background; the Schwarzschild case seems more subtle. We discuss a potential limitation of the procedure when applying it to explicit time-dependent backgrounds.

Description: A well-established phenomenon in general relativity is the dragging of inertial frames by a spinning object. In particular, due to the dragging of inertial frames by a ring orbiting a central black hole, the angular velocity \(\Omega ^{\text {BH-ring}}_{\text {H}}\) of the black-hole horizon in the composed black-hole–ring system is no longer related to the black-hole angular momentum \(J_{\text {H}}\) by the simple Kerr-like (vacuum) relation \(\Omega ^{\text {Kerr}}_{\text {H}}(J_{\text {H}})=J_{\text {H}}/2M^2R_{\text {H}}\) (here M and \(R_{\text {H}}\) are the mass and horizon-radius of the black hole, respectively). Will has performed a perturbative treatment of the composed black-hole–ring system in the regime of slowly rotating black holes and found the explicit relation \(\Omega ^{\text {BH-ring}}_{\text {H}}(J_{\text {H}}=0,J_{\text {R}},R)=2J_{\text {R}}/R^3\) for the angular velocity of a central black hole with zero angular momentum, where \(J_{\text {R}}\) and R are respectively the angular momentum of the orbiting ring and its proper circumferential radius. Analyzing a sequence of black-hole–ring configurations with adiabatically varying (decreasing) circumferential radii, we show that the expression found by Will for \(\Omega ^{\text {BH-ring}}_{\text {H}}(J_{\text {H}}=0,J_{\text {R}},R)\) implies a smooth transition of the central black-hole angular velocity from its asymptotic near-horizon value \(\Omega ^{\text {BH-ring}}_{\text {H}}(J_{\text {H}}=0,J_{\text {R}},R\rightarrow R^{+}_{\text {H}})\rightarrow 2J_{\text {R}}/R^3_{\text {H}}\) (that is, just before the assimilation of the ring by the central black hole), to its final Kerr (vacuum) value \(\Omega ^{\text {Kerr}}_{\text {H}}(J^{\text {new}}_{\text {H}})= J^{\text {new}}_{\text {H}}/2{M^{\text {new}}}^2R^{\text {new}}_{\text {H}}\) [that is, after the adiabatic assimilation of the ring by the central black hole. Here \(J^{\text {new}}_{\text {H}}=J_{\text {R}}\) , \(M^{\text {new}}\) , and \(R^{\text {new}}_{\text {H}}\) are the new parameters of the resulting Kerr (vacuum) black hole after it assimilated the orbiting ring]. We use this important observation in order to generalize the result of Will to the regime of black-hole–ring configurations in which the central black holes possess non-zero angular momenta. In particular, it is shown that the continuity argument (namely, the characteristic smooth evolution of the black-hole angular velocity during an adiabatic assimilation process of the ring into the central black hole) yields a concrete prediction for the angular-velocity/angular-momentum asymptotic functional relation \(\Omega ^{\text {BH-ring}}_{\text {H}}=\Omega ^{\text {BH-ring}}_{\text {H}}(J_{\text {H}},J_{\text {R}},R\rightarrow R^{+}_{\text {H}})\) of generic (that is, with \(J_{\text {H}}\ne 0\) ) black-hole–ring configurations. Remarkably, we find the simple universal relation \(\Delta \Omega _{\text {H}}\equiv \Omega ^{\text {BH-ring}}_{\text {H}}(J_{\text {H}},J_{\text {R}},R\rightarrow R^{+}_{\text {H}})-\Omega ^{\text {Kerr}}_{\text {H}}(J_{\text {H}})={{J_{\text {R}}}/{4M^3}}\) for the asymptotic deviation of the black-hole angular velocity in the composed black-hole–ring system from the corresponding angular velocity of the unperturbed (vacuum) Kerr black hole with the same angular momentum.

Description: As an extension of previous works on classical tests of Kaluza–Klein (KK) gravity and as an attempt to find more stringent constraints on this theory, its effects on physical experiments and astronomical observations conducted in the Solar System are studied. We investigate the gravitational time delay at inferior conjunction caused by KK gravity, and use new Solar System ephemerides and the observation of Cassini to strengthen constraints on KK gravity by up to two orders of magnitude. These improved upper bounds mean that the fifth-dimensional space in the soliton case is a very flat extra dimension in the Solar System, even in the vicinity of the Sun.

Description: The normalized differential cross section for top quark pair ( \({\mathrm{t}}\overline{{\mathrm{t}}}\) ) production is measured in pp collisions at a centre-of-mass energy of 8 \(\,\text {TeV}\) at the CERN LHC using the CMS detector in data corresponding to an integrated luminosity of 19.7 \(\,\text {fb}^{-1}\) . The measurements are performed in the lepton \(+\) jets ( \(\mathrm {e}/\mu \) \(+\) jets) and in the dilepton ( \(\mathrm {e}^+\mathrm {e}^-\) , \(\mu ^+ \mu ^- \) , and \(\mathrm {e}^\pm \mu ^{\mp }\) ) decay channels. The \({\mathrm{t}}\overline{{\mathrm{t}}}\) cross section is measured as a function of the kinematic properties of the charged leptons, the jets associated to b quarks, the top quarks, and the \({\mathrm{t}}\overline{{\mathrm{t}}}\) system. The data are compared with several predictions from perturbative quantum chromodynamic up to approximate next-to-next-to-leading-order precision. No significant deviations are observed relative to the standard model predictions.

Description: Recently we have shown that for \(2+1\) -dimensional thin-shell wormholes a non-circular throat may lead to a physical wormhole in the sense that the energy conditions are satisfied. By the same token, herein we consider an angular dependent throat geometry embedded in a \(2+1\) -dimensional flat spacetime in polar coordinates. It is shown that, remarkably, a generic, natural example of the throat geometry is provided by a hypocycloid. That is, two flat \(2+1\) dimensions are glued together along a hypocycloid. The energy required in each hypocycloid increases with the frequency of the roller circle inside the large one.

Description: We propose a parametrization for interpreting some of the presently available data of the \(B^{\pm } \rightarrow K^{\pm } p {\bar{p}}\) decay, in particular those by the LHCb and Belle Collaborations. The model is inspired by the well-known current and transition contributions, usually assumed in this kind of decay. However, in the light of considerations as regards the dominant diagrams and final state interactions, we modify some parameters of the model, determining them by means of a best fit to the data. We show the results, which we discuss in some detail. Moreover, we give some predictions on other observables relative to the decays.

Description: We have set up a light scattering spectrometer to study the depolarization of light scattering in linear alkylbenzene. The scattering spectra show that the depolarized part of light scattering is due to Rayleigh scattering. The additional depolarized Rayleigh scattering can make the effective transparency of linear alkylbenzene much better than expected. Therefore, sufficient scintillation photons can transmit through large liquid scintillator detector, such as that of the JUNO experiment. Our study is crucial to achieving an unprecedented energy resolution of 3 %/ \(\sqrt{E\mathrm {(MeV)}}\) required for the JUNO experiment to determine the neutrino mass hierarchy. The spectroscopic method can also be used to examine the depolarization of other organic solvents used in neutrino experiments.

Description: During the inflationary epoch, the geometry of the universe may be described by a quasi-de Sitter space. On the other hand, the maximally extended de Sitter metric in the comoving coordinates accords with a special FLRW model with positive spatial curvature; therefore, the focus of the present paper is on the positively curved inflationary paradigm, for which we first of all derive the power spectra of comoving curvature perturbation and primordial gravitational waves in a positively curved FLRW universe according to the slowly rolling inflationary scenario. It can be shown that the curvature spectral index in this model automatically has a small negative running parameter, compatible with observational measurements. Afterwards, by taking into account the curvature factor, it investigates the relative amplitude of the scalar and tensor perturbations, clarifying that the tensor–scalar ratio for this model, against the spatially flat one, directly depends on the wavelength of the perturbative modes.

Description: The low-background, VUV-sensitive 3-inch diameter photomultiplier tube R11410 has been developed by Hamamatsu for dark matter direct detection experiments using liquid xenon as the target material. We present the results from the joint effort between the XENON collaboration and the Hamamatsu company to produce a highly radio-pure photosensor (version R11410-21) for the XENON1T dark matter experiment. After introducing the photosensor and its components, we show the methods and results of the radioactive contamination measurements of the individual materials employed in the photomultiplier production. We then discuss the adopted strategies to reduce the radioactivity of the various PMT versions. Finally, we detail the results from screening 286 tubes with ultra-low background germanium detectors, as well as their implications for the expected electronic and nuclear recoil background of the XENON1T experiment.

Description: LArGe is a Gerda low-background test facility to study novel background suppression methods in a low-background environment, for future application in the Gerda experiment. Similar to Gerda , LArGe operates bare germanium detectors submersed into liquid argon (1 m \(^3\) , 1.4 tons), which in addition is instrumented with photomultipliers to detect argon scintillation light. The scintillation signals are used in anti-coincidence with the germanium detectors to effectively suppress background events that deposit energy in the liquid argon. The background suppression efficiency was studied in combination with a pulse shape discrimination (PSD) technique using a BEGe detector for various sources, which represent characteristic backgrounds to Gerda . Suppression factors of a few times \(10^3\) have been achieved. First background data of LArGe with a coaxial HPGe detector (without PSD) yield a background index of (0.12 \(-\) 4.6) \(\times 10^{-2}\) cts/(keV kg year) (90 % C.L.), which is at the level of Gerda Phase I. Furthermore, for the first time we monitor the natural \(^{42}\) Ar abundance (parallel to Gerda ), and have indication for the \(2\nu \beta \beta \) -decay in natural germanium. These results show the effectivity of an active liquid argon veto in an ultra-low background environment. As a consequence, the implementation of a liquid argon veto in Gerda Phase II is pursued.

Description: We explore the entropy spectrum of \((1+1)\) dimensional dilatonic stringy black holes via the adiabatic invariant integral method known as Jiang and Han’s method (Phys Lett B 718:584, 2012 ) and the Bohr–Sommerfeld quantization rule. It is found that the corresponding spectrum depends on black hole parameters like charge, ADM mass, and, more interestingly, on the dilatonic field. We calculate the entropy of the present black hole system via the Euclidean treatment of quantum gravity and study the thermodynamics of the black hole and find that the system does not undergo any phase transition.

Description: We calculate the shape of the \(\pi \Sigma \) and \(\bar{K} N\) invariant mass distributions in the \(\Lambda _b \rightarrow J/\psi \, \pi \Sigma \) and \(\Lambda _b \rightarrow J/\psi \,\bar{K} N\) decays that are dominated by the \(\Lambda (1405)\) resonance. The weak interaction part is the same for both processes and the hadronization into the different meson–baryon channels in the final state is given by symmetry arguments. The most important feature is the implementation of the meson–baryon final-state interaction using two chiral unitary models from different theoretical groups. Both approaches give a good description of antikaon–nucleon scattering data, the complex energy shift in kaonic hydrogen and the line shapes of \(\pi \Sigma K\) in photoproduction, based on the two-pole scenario for the \(\Lambda (1405)\) . We find that this reaction reflects more the higher mass pole and we make predictions of the line shapes and relative strength of the meson–baryon distributions in the final state.

Description: In the framework of heavy quark effective theory, the leading-order Isgur–Wise form factors relevant to semileptonic decays of the ground state \(\bar{b}s\) meson \(B_{s}\) into orbitally excited \(D\) -wave \(\bar{c}s\) mesons, including the newly observed narrow \(D^{*}_{s1}(2860)\) and \(D^{*}_{s3}(2860)\) states by the LHCb Collaboration, are calculated with the QCD sum rule method. With these universal form factors, the decay rates and branching ratios are estimated. We find that the decay widths are \(\Gamma (B_s\rightarrow D^{*}_{s1}\ell \overline{\nu }) =1.25^{+0.80}_{-0.60}\times 10^{-19}\,\text{ GeV }\) , \(\Gamma (B_s\rightarrow D^{'}_{s2}\ell \overline{\nu }) =1.49^{+0.97}_{-0.73}\times 10^{-19}\,\text{ GeV }\) , \(\Gamma (B_s\rightarrow D_{s2}\ell \overline{\nu }) =4.48^{+1.05}_{-0.94}\times 10^{-17}\,\text{ GeV }\) , and \(\Gamma (B_s\rightarrow D^{*}_{s3}\ell \overline{\nu }) = 1.52^{+0.35}_{-0.31}\times 10^{-16}\,\text{ GeV }\) . The corresponding branching ratios are \(\mathcal {B}(B_s\rightarrow D^{*}_{s1}\ell \overline{\nu }) =2.85^{+1.82}_{-1.36}\times 10^{-7}\) , \(\mathcal {B}(B_s\rightarrow D^{'}_{s2}\ell \overline{\nu }) =3.40^{+2.21}_{-1.66}\times 10^{-7}\) , \(\mathcal {B}(B_{s}\rightarrow D_{s2}\ell \overline{\nu }) =1.02^{+0.24}_{-0.21}\times 10^{-4}\) , and \(\mathcal {B}(B_s\rightarrow D^{*}_{s3}\ell \overline{\nu }) = 3.46^{+0.80}_{-0.70}\times 10^{-4}\) . The decay widths and branching ratios of corresponding \(B^{*}_{s}\) semileptonic processes are also predicted.

Description: Bekenstein has put forward the idea that, in a quantum theory of gravity, a black hole should have a discrete energy spectrum with concomitant discrete line emission. The quantized black-hole radiation spectrum is expected to be very different from Hawking’s semi-classical prediction of a thermal black-hole radiation spectrum. One naturally wonders: Is it possible to reconcile the discrete quantum spectrum suggested by Bekenstein with the continuous semi-classical spectrum suggested by Hawking? In order to address this fundamental question, in this essay we shall consider the zero-point quantum-gravity fluctuations of the black-hole spacetime. In a quantum theory of gravity, these spacetime fluctuations are closely related to the characteristic gravitational resonances of the corresponding black-hole spacetime. Assuming that the energy of the black-hole radiation stems from these zero-point quantum-gravity fluctuations of the black-hole spacetime, we derive the effective temperature of the quantized black-hole radiation spectrum. Remarkably, it is shown that this characteristic temperature of the discrete (quantized) black-hole radiation agrees with the well-known Hawking temperature of the continuous (semi-classical) black-hole spectrum.

Description: For the search for additional Higgs bosons in the minimal supersymmetric standard model (MSSM) as well as for future precision analyses in the Higgs sector a precise knowledge of their decay properties is mandatory. We evaluate all two-body decay modes of the Higgs bosons into charginos and neutralinos in the MSSM with complex parameters (cMSSM). The evaluation is based on a full one-loop calculation of all decay channels, also including hard QED radiation. We restricted ourselves to a version of our renormalization scheme which is valid for \(|M_1| 〈 |M_2|, |\mu |\) and \(M_2 \ne \mu \) to simplify the analysis, even though we are able to switch to other parameter regions. The dependence of the Higgs boson predictions on the relevant cMSSM parameters is analyzed numerically. We find sizable contributions to many partial decay widths. They are roughly of 10 % of the tree-level results, but they can go up to 20 % or higher. The full one-loop contributions are important for the correct interpretation of heavy Higgs boson search results at the LHC and, if kinematically allowed, at a future linear \(e^+e^-\) collider. There are plans to implement the evaluation of the branching ratios of the Higgs bosons into the Fortran code FeynHiggs , together with an automated choice of the renormalization scheme valid for the full cMSSM parameter space.

Description: *************Abstract Double-differential three-jet production cross-sections are measured in proton–proton collisions at a centre-of-mass energy of \(\sqrt{s} = 7\mathrm \,TeV{}\) using the ATLAS detector at the large hadron collider. The measurements are presented as a function of the three-jet mass \((m_{jjj})\) , in bins of the sum of the absolute rapidity separations between the three leading jets \((\left| Y^{*}\right| )\) . Invariant masses extending up to 5  TeV are reached for \(8〈 \left| Y^{*}\right| 〈 10\) . These measurements use a sample of data recorded using the ATLAS detector in 2011, which corresponds to an integrated luminosity of \(4.51~\text{ fb }^{-1}\) . Jets are identified using the anti- \(k_{t}\) algorithm with two different jet radius parameters, \(R=0.4\) and \(R=0.6\) . The dominant uncertainty in these measurements comes from the jet energy scale. Next-to-leading-order QCD calculations corrected to account for non-perturbative effects are compared to the measurements. Good agreement is found between the data and the theoretical predictions based on most of the available sets of parton distribution functions, over the full kinematic range, covering almost seven orders of magnitude in the measured cross-section values.

Description: In the present paper the results obtained in the investigation of possible diurnal effects for low-energy single-hit scintillation events of DAMA/LIBRA-phase1 (1.04 ton \(\times \) year exposure) have been analysed in terms of an effect expected in case of dark matter (DM) candidates inducing nuclear recoils and having high cross-section with ordinary matter, which implies low DM local density in order to fulfill the DAMA/LIBRA DM annual modulation results. This effect is due to the different Earth depths crossed by those DM candidates during the sidereal day.

Description: Transverse momentum spectra of charged particles are measured by the CMS experiment at the CERN LHC in pPb collisions at \(\sqrt{s_{_\mathrm {NN}}} =5.02\) \(\,\text {TeV}\) , in the range \(0.4 〈 p_{\mathrm {T}} 〈 120\) \({\,\text {GeV/}c}\) and pseudorapidity \(|\eta _\textsc {cm} | 〈 1.8\) in the proton–nucleon center-of-mass frame. For \(p_{\mathrm {T}} 〈10\) \({\,\text {GeV/}c}\) , the charged-particle production is asymmetric about \(\eta _\textsc {cm} = 0\) , with smaller yield observed in the direction of the proton beam, qualitatively consistent with expectations from shadowing in nuclear parton distribution functions (nPDF). A pp reference spectrum at \(\sqrt{s}=5.02\) \(\,\text {TeV}\) is obtained by interpolation from previous measurements at higher and lower center-of-mass energies. The \(p_{\mathrm {T}}\) distribution measured in pPb collisions shows an enhancement of charged particles with \(p_{\mathrm {T}} 〉20\) \({\,\text {GeV/}c}\) compared to expectations from the pp reference. The enhancement is larger than predicted by perturbative quantum chromodynamics calculations that include antishadowing modifications of nPDFs.

Description: ColorFull , a C++ package for treating QCD color structure, is presented. ColorFull , which utilizes the trace basis approach, is intended for interfacing with event generators, but can also be used as a stand-alone package for squaring QCD amplitudes, calculating interferences, and describing the effect of gluon emission and gluon exchange.

Description: In this paper we analyze the double vector meson production in photon–hadron ( \(\gamma h\) ) interactions at pp  /  pA  /  AA collisions and present predictions for the \(\rho \rho \) , \(J/\Psi J/\Psi \) , and \(\rho J/\Psi \) production considering the double scattering mechanism. We estimate the total cross sections and rapidity distributions at LHC energies and compare our results with the predictions for the double vector meson production in \(\gamma \gamma \) interactions at hadronic colliders. We present predictions for the different rapidity ranges probed by the ALICE, ATLAS, CMS, and LHCb Collaborations. Our results demonstrate that the \(\rho \rho \) and \(J/\Psi J/\Psi \) production in PbPb collisions is dominated by the double-scattering mechanism, while the two-photon mechanism dominates in pp collisions. Moreover, our results indicate that the analysis of the \(\rho J/\Psi \) production at LHC can be useful to constrain the double-scattering mechanism.

Description: We consider special supersymmetry (SUSY) transformations with m generators \(\overleftarrow{s}_\alpha ,\) for some class of models and study the physical consequences when making the Grassmann-odd transformations to form an Abelian supergroup with finite parameters and a set of group-like elements with finite parameters being functionals of the field variables. The SUSY-invariant path integral measure within conventional quantization scheme leads to the appearance of the Jacobian under a change of variables generated by such SUSY transformations, which is explicitly calculated. The Jacobian implies, first of all, the appearance of trivial interactions in the transformed action, and, second, the presence of a modified Ward identity which reduces to the standard Ward identities in the case of constant parameters. We examine the case of the \({N}=1\) and \(N=2\) supersymmetric harmonic oscillators to illustrate the general concept by a simple free model with (1, 1) physical degrees of freedom. It is shown that the interaction terms \(U_{\mathrm{tr}}\) have a corresponding SUSY-exact form: \(U_{\mathrm{tr}}= \big (V_{(1)}\overleftarrow{s}; V_{(2)}\overleftarrow{\bar{s}} \overleftarrow{s}\big )\) generated naturally under such generalized formulation. We argue that the case of a non-trivial interaction cannot be obtained in such a way.

Description: A search for squarks and gluinos in final states containing hadronic jets, missing transverse momentum but no electrons or muons is presented. The data were recorded in 2015 by the ATLAS experiment in \(\sqrt{s}=13~{\mathrm{TeV}}\) proton–proton collisions at the Large Hadron Collider. No excess above the Standard Model background expectation was observed in 3.2  \(\mathrm{fb}^{-1}\) of analyzed data. Results are interpreted within simplified models that assume R -parity is conserved and the neutralino is the lightest supersymmetric particle. An exclusion limit at the 95 % confidence level on the mass of the gluino is set at 1.51  \({\mathrm{TeV}}\) for a simplified model incorporating only a gluino octet and the lightest neutralino, assuming the lightest neutralino is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.03  \({\mathrm{TeV}}\) are excluded for a massless lightest neutralino. These limits substantially extend the region of supersymmetric parameter space excluded by previous measurements with the ATLAS detector.

Description: The low-energy and high-energy behavior of the pion–photon transition form factor \(F_{\pi \gamma }(Q^2)\) are sensitive to the transverse and longitudinal distributions of the pion wave function, respectively. A careful study of \(F_{\pi \gamma }(Q^2)\) shall thus provide helpful constraints on the properties of the pion wave function. In this paper, we present a combined analysis of the data on \(F_{\pi \gamma }(Q^2)\) reported by the CELLO, the CLEO, the BABAR, and the BELLE Collaborations. It is performed by using the method of least squares. By using the combined measurements of the BELLE and CLEO Collaborations, the pion wave function longitudinal and transverse behavior can be fixed to a certain degree, i.e. we obtain \(\beta \in [0.691,0.757]\)  GeV and \(B \in [0.00,0.235]\) for \(P_{\chi ^2} \ge 90\,\%\) , where \(\beta \) and B are two parameters of a convenient pion wave function model. It is noted that the distribution amplitude of such a pion wave function can mimic various longitudinal behaviors, as suggested in the literature under a proper choice of parameters. We observe that the CELLO, CLEO, and BELLE data are consistent with each other, all of which prefer the asymptotic-like distribution amplitude; while the BABAR data prefers a more broad distribution amplitude, such as the CZ-like one.

Description: The Einstein–Hilbert action in the context of higher derivative theories is considered for finding their BRST symmetries. Being a constraint system, the model is transformed in the minisuperspace language with the FRLW background and the gauge symmetries are explored. Exploiting the first order formalism developed by Banerjee et al. the diffeomorphism symmetry is extracted. From the general form of the gauge transformations of the field, the analogous BRST transformations are calculated. The effective Lagrangian is constructed by considering two gauge-fixing conditions. Further, the BRST (conserved) charge is computed, which plays an important role in defining the physical states from the total Hilbert space of states. The finite field-dependent BRST formulation is also studied in this context where the Jacobian for the functional measure is illustrated specifically.

Description: Recently the ANTARES collaboration presented a time dependent analysis of a selected number of flaring blazars to look for upward going muon events produced from the charge current interaction of the muon neutrinos. We use the same list of flaring blazars to look for a possible positional correlation with the IceCube neutrino events. In the context of the photohadronic model we propose that the neutrinos are produced within the nuclear region of the blazar where Fermi accelerated high energy protons interact with the background synchrotron/SSC photons. Although we found that some objects from the ANTARES list are within the error circles of a few IceCube events, the statistical analysis shows that none of these sources have a significant correlation.

Description: A measurement of the W boson pair production cross section in proton-proton collisions at \(\sqrt{s} = 8\)  TeV is presented. The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 19.4 \(\,\text {fb}^\text {-1}\) . The \({{\mathrm{W} }^{+} }\mathrm{W}^{-} \) candidates are selected from events with two charged leptons, electrons or muons, and large missing transverse energy. The measured \({{\mathrm{W} }^{+} }\mathrm{W}^{-} \) cross section is \(60.1\pm 0.9\,\text {(stat)} \pm 3.2\,\text {(exp)} \pm 3.1\,\text {(theo)} \pm 1.6\,\text {(lumi)} \text {\,pb} = 60.1\pm 4.8\text {\,pb} \) , consistent with the standard model prediction. The \({{\mathrm{W} }^{+} }\mathrm{W}^{-} \) cross sections are also measured in two different fiducial phase space regions. The normalized differential cross section is measured as a function of kinematic variables of the final-state charged leptons and compared with several perturbative QCD predictions. Limits on anomalous gauge couplings associated with dimension-six operators are also given in the framework of an effective field theory. The corresponding 95 % confidence level intervals are \(-5.7〈 c_{\mathrm {WWW}}/\Lambda ^2 〈 5.9\,\mathrm{TeV}^{-2}\) , \(-11.4〈 c_{\mathrm {W}}/\Lambda ^2 〈 5.4\,\mathrm{TeV}^{-2}\) , \(-29.2〈 c_{\mathrm {B}}/\Lambda ^2 〈 23.9\,\mathrm{TeV}^{-2}\) , in the HISZ basis.

Description: The thermodynamic entropy of an isolated system is given by its von Neumann entropy. Over the last few years, there has been an intense activity to understand the thermodynamic entropy from the principles of quantum mechanics. More specifically, is there a relation between the (von Neumann) entropy of entanglement between a system and some (separate) environment and the thermodynamic entropy? It is difficult to obtain the relation for many body systems, hence, most of the work in the literature has focused on small number systems. In this work, we consider black holes—which are simple yet macroscopic systems—and show that a direct connection could not be made between the entropy of entanglement and the Hawking temperature. In this work, within the adiabatic approximation, we explicitly show that the Hawking temperature is indeed given by the rate of change of the entropy of entanglement across a black hole’s horizon with regard to the system energy. This is yet other numerical evidence leading to understanding the key features of black-hole thermodynamics from the viewpoint of quantum information theory.

Description: This paper explores the dynamics of particles in higher dimensions. For this purpose, we discuss some interesting features related to the motion of particles near a Myers–Perry black hole with arbitrary extra dimensions as well as a single non-zero spin parameter. Assuming it as a supermassive black hole at the center of the galaxy, we calculate red–blue shifts in the equatorial plane for the far away observer as well as the corresponding black hole parameters of the photons. Next, we study the Penrose process and find that the energy gain of the particle depends on the variation of the black hole dimensions. Finally, we discuss the center of mass energy for 11 dimensions, which indicates a similar behavior to that of four dimensions but it is higher in four dimensions than five or more dimensions. We conclude that higher dimensions have a great impact on the particle dynamics.

Description: In high-energy collisions of heavy ions, experimental findings of collective flow are customarily associated with the presence of a thermalized medium expanding according to the laws of hydrodynamics. Recently, the ATLAS, CMS, and ALICE experiments found signals of the same type and magnitude in ultrarelativistic proton–proton collisions. In this study, the state-of-the-art hydrodynamic model SONIC is used to simulate the systems created in p+p collisions. By varying the size of the second-order transport coefficients, the range of applicability of hydrodynamics itself to the systems created in p+p collisions is quantified. It is found that hydrodynamics can give quantitatively reliable results for the particle spectra and the elliptic momentum anisotropy coefficient \(v_2\) . Using a simple geometric model of the proton based on the elastic form factor leads to results of similar type and magnitude to those found in experiment when allowing for a small bulk viscosity coefficient.

Description: The Wigner distributions for the u and the d quarks in a proton are calculated using the light-front wave functions of the scalar quark–diquark model for a nucleon constructed from the soft-wall AdS/QCD correspondence. We present a detailed study of the quark orbital angular momentum and its correlation with the quark spin and the proton spin. The quark density distributions, considering the different polarizations of quarks and proton, in transverse momentum plane as well as in transverse impact parameter plane are presented for both u and d quarks.

Description: The oscillation frequency, \(\Delta m_d\) , of \(B^0\) mesons is measured using semileptonic decays with a \(D^-\) or \(D^{*-}\) meson in the final state. The data sample corresponds to 3.0 \(fb^{-1}\) of pp collisions, collected by the LHCb experiment at centre-of-mass energies \(\sqrt{s}\) = 7 and 8 \(\mathrm \,TeV\) . A combination of the two decay modes gives \(\Delta m_d = (505.0 \pm 2.1 \pm 1.0) \mathrm \,ns^{-1}\) , where the first uncertainty is statistical and the second is systematic. This is the most precise single measurement of this parameter. It is consistent with the current world average and has similar precision.

Description: We compute the next-to-leading order virtual QCD corrections to Higgs-pair production via gluon fusion. We present analytic results for the two-loop contributions to the spin-0 and spin-2 form factors in the amplitude. The reducible contributions, given by the double-triangle diagrams, are evaluated exactly while the two-loop irreducible diagrams are evaluated by an asymptotic expansion in heavy top-quark mass up to and including terms of \(\mathcal {O}(1/m_t^8)\) . Assuming that the finite top-quark mass effects are of similar size in the entire range of partonic energies, we estimate that mass effects can reduce the hadronic cross section by at most \(10~\%\) .

Description: In this paper we study cosmological dynamics of the phantom as well as non-phantom fields with a linear potential in the presence of a Galileon correction \( (\partial _\mu \phi \partial ^\mu \phi ) \Box \phi \) . We show that the Big Crunch singularity is delayed compared to the standard case; the delay crucially depends upon the strength of a Galileon correction. As for the phantom Galileon, \(\rho _{\phi }\) is shown to grow more slowly compared to the standard phantom delaying the approach of the singularity. In the case, \(V\sim \phi ^n, n〉4\) , Big Rip is also delayed, similar phenomenon is shown to take place for potentials steeper than the exponential.

Description: In this work we investigate the transition from kinks to compactons at high temperatures. We deal with a family of models, described by a real scalar field with standard kinematics, controlled by a single parameter, real and positive. The family of models supports kink-like solutions, and the solutions tend to become compact when the parameter increases to larger and larger values. We study the one-loop corrections at finite temperature, to see how the thermal effects add to the effective potential. The results suggest that the symmetry is restored at very high temperatures.

Description: Two major problems, still associated with the SN1987A, are: (a) the signals observed with the gravitational waves detectors, (b) the duration of the collapse. Indeed, (a) the sensitivity of the gravitational wave detectors seems to be small for detecting gravitational waves and, (b) while some experimental data indicate a duration of order of hours, most theories assume that the collapse develops in a few seconds. Since recent data of the X-ray NuSTAR satellite show a clear evidence of an asymmetric collapse, we have revisited the experimental data recorded by the underground and gravitational wave detectors running during the SN1987A. New evidence is shown that confirms previous results, namely that the data recorded by the gravitational wave detectors running in Rome and in Maryland are strongly correlated with the data of both the Mont Blanc and the Kamiokande detectors, and that the correlation extends over a long period of time (1 or 2 h) centered at the Mont Blanc time. This result indicates that also Kamiokande detected neutrinos at the Mont Blanc time, and these interactions were not identified because not grouped in a burst.

Description: In this article, we assume that the nonet scalar mesons below \(1\,\mathrm { GeV}\) are the two-quark–tetraquark mixed states and study their masses and pole residues using the QCD sum rules. In the calculation, we take into account the vacuum condensates up to dimension 10 and the \(\mathcal {O}(\alpha _s)\) corrections to the perturbative terms in the operator product expansion. We determine the mixing angles, which indicate the two-quark components are much larger than \(50~\%\) , then we obtain the masses and pole residues of the nonet scalar mesons.

Description: We calculate the cross sections of electromagnetic productions of muon- and tauon-pair productions from the ultra-relativistic heavy ion collisions. Since the Compton wavelengths of muon and tauon are comparable to the radius of the colliding ions, nuclear form factors play important roles for calculating the cross sections. Recent measurement (Abrahamyan et al., Phys Rev Lett 108:112502, 2012 ) indicates that the neutrons are differently distributed from the protons; therefore this affects the cross section of the heavy-lepton pair production. In order to see the effects of the neutron distributions in the nucleus, we used analytical expression of the Fourier transforms of the Wood–Saxon distribution. Cross section calculations show that the Wood–Saxon distribution function is more sensitive to the parameter R compared to the parameter a .

Description: A \((n+1)\) -dimensional gravitational model with Gauss–Bonnet term and a cosmological constant term is considered. When ansatz with diagonal cosmological metrics is adopted, the solutions with an exponential dependence of the scale factors, \(a_i \sim \exp { ( v^i t) }\) , \(i =1, \dots , n \) , are analyzed for \(n 〉 3\) . We study the stability of the solutions with non-static volume factor, i.e. if \(K(v) = \sum _{k = 1}^{n} v^k \ne 0\) . We prove that under a certain restriction R imposed solutions with \(K(v) 〉 0\) are stable, while solutions with \(K(v) 〈 0\) are unstable. Certain examples of stable solutions are presented. We show that the solutions with \(v^1 = v^2 =v^3 = H 〉 0\) and zero variation of the effective gravitational constant are stable if the restriction R is obeyed.

Description: In this paper we argue that minimal supergravity with a flat Kähler metric and a power-law superpotential can relate the Super-Higgs mechanism for the local spontaneous supersymmetry breaking and the cosmological tracking solution, leading in turn to a late-time accelerated expansion of the universe and alleviating the coincidence problem.

Description: A large effort has been carried out to characterize the background of sodium iodide crystals within the Annual modulation with NaI Scintillators (ANAIS) project. In this paper, the background models developed for three 12.5 kg NaI(Tl) scintillators produced by Alpha Spectra Inc. and operated at the Canfranc Underground Laboratory are presented together with an evaluation of the background prospects for the full experiment. Measured spectra from threshold to high energy in different conditions are well described by the models based on quantified activities. At the region of interest, crystal bulk contamination is the dominant background source. Contributions from \(^{210}\) Pb, \(^{40}\) K, \(^{22}\) Na and \(^{3}\) H are the most relevant. Those from \(^{40}\) K and \(^{22}\) Na could be efficiently suppressed thanks to anticoincidence operation in a crystals matrix or inside a liquid scintillator veto (LSV), while that from \(^{210}\) Pb has been reduced by improving crystal production methods and \(^{3}\) H production could be reduced by shielding against cosmic rays during production. Assuming the activities of the last characterized detector, for nine crystals with a total mass of 112.5 kg the expected background rate is 2.5 counts/(keV kg day) in the region from 1 to 4 keV, which could be reduced at 1.4 counts/(keV kg day) by using a LSV.

Description: We study the conditions of restoring supersymmetry (SUSY) after inflation in the supergravity-based cosmological models with a single chiral superfield and a quartic stabilization term in the Kähler potential. Some new, explicit, and viable inflationary models satisfying those conditions are found. The inflaton’s scalar superpartner is dynamically stabilized during and after inflation. We also demonstrate a possibility of having small and adjustable SUSY breaking with a tiny cosmological constant.

Description: We develop a Bloch vector representation of the Unruh channel for a Dirac field mode. This is used to provide a unified, analytical treatment of quantum Fisher and skew information for a qubit subjected to the Unruh channel, both in its pure form as well as in the presence of experimentally relevant external noise channels. The time evolution of Fisher and skew information is studied along with the impact of external environment parameters such as temperature and squeezing. The external noises are modelled by both purely dephasing phase damping and the squeezed generalised amplitude damping channels. An interesting interplay between the external reservoir temperature and squeezing on the Fisher and skew information is observed, in particular, for the action of the squeezed generalised amplitude damping channel. It is seen that for some regimes, squeezing can enhance the quantum information against the deteriorating influence of the ambient environment. Similar features are also observed for the analogous study of skew information, highlighting a similar origin of the Fisher and skew information.

Description: Newton–Cartan geometry has played a central role in recent discussions of the non-relativistic holography and condensed matter systems. Although the conformal transformation in non-relativistic holography can easily be rephrased in terms of Newton–Cartan geometry, we show that it requires a nontrivial procedure to arrive at the consistent form of anisotropic disformal transformation in this geometry. Furthermore, as an application of the newly obtained transformation, we use it to induce a geometric structure which may be seen as a particular non-relativistic version of the Weyl integrable geometry.

Description: The proton charge radius inferred from muonic hydrogen spectroscopy is not compatible with the previous value given by CODATA-2010, which, on its turn, essentially relies on measurements of the electron–proton interaction. The proton’s new size was extracted from the 2S–2P Lamb shift in the muonic hydrogen, which showed an energy excess of 0.3 meV in comparison to the theoretical prediction, evaluated with the CODATA radius. Higher-dimensional gravity is a candidate to explain this discrepancy, since the muon–proton gravitational interaction is stronger than the electron–proton interaction and, in the context of braneworld models, the gravitational potential can be hugely amplified in short distances when compared to the Newtonian potential. Motivated by these ideas, we study a muonic hydrogen confined in a thick brane. We show that the muon–proton gravitational interaction modified by extra dimensions can provide the additional separation of 0.3 meV between the 2S and 2P states. In this scenario, the gravitational energy depends on the higher-dimensional Planck mass and indirectly on the brane thickness. Studying the behavior of the gravitational energy with respect to the brane thickness in a realistic range, we find constraints for the fundamental Planck mass that solve the proton radius puzzle and are consistent with previous experimental bounds.

Description: The present work suggests that the isocurvature tension between axion and high energy inflationary scenarios may be avoided by considering a double field inflationary model involving the hidden Peccei–Quinn Higgs and the Standard Model one. Some terms in the lagrangian we propose explicitly violate the Peccei–Quinn symmetry but, at the present era, their effect is completely negligible. The resulting mechanism allows for a large value for the axion constant, of the order \(f_a\sim M_p\) , thus the axion isocurvature fluctuations are suppressed even when the scale of inflation \(H_{\mathrm{inf}}\) is very high, of the order of \(H_{\mathrm{inf}}\sim M_{\mathrm{gut}}\) . This numerical value is typical in Higgs inflationary models. An analysis about topological defect formation in this scenario is also performed, and it is suggested that, under certain assumptions, their effect is not catastrophic from the cosmological point of view.

Description: We study the charmless two-body \(\Lambda _b\rightarrow \Lambda (\phi ,\eta ^{(\prime )})\) and three-body \(\Lambda _b\rightarrow \Lambda K^+K^- \) decays. We obtain \(\mathcal{B}(\Lambda _b\rightarrow \Lambda \phi )=(3.53\pm 0.24)\times 10^{-6}\) to agree with the recent LHCb measurement. However, we find that \(\mathcal{B}(\Lambda _b\rightarrow \Lambda (\phi \rightarrow )K^+ K^-)=(1.71\pm 0.12)\times 10^{-6}\) is unable to explain the LHCb observation of \(\mathcal{B}(\Lambda _b\rightarrow \Lambda K^+ K^-)=(15.9\pm 1.2\pm 1.2\pm 2.0)\times 10^{-6}\) , which implies the possibility for other contributions, such as that from the resonant \(\Lambda _b\rightarrow K^- N^*,\,N^*\rightarrow \Lambda K^+\) decay with \(N^*\) as a higher-wave baryon state. For \(\Lambda _b\rightarrow \Lambda \eta ^{(\prime )}\) , we show that \(\mathcal{B}(\Lambda _b\rightarrow \Lambda \eta ,\,\Lambda \eta ^\prime )= (1.47\pm 0.35,1.83\pm 0.58)\times 10^{-6}\) , which are consistent with the current data of \((9.3^{+7.3}_{-5.3},〈3.1)\times 10^{-6}\) , respectively. Our results also support the relation of \(\mathcal{B}(\Lambda _b\rightarrow \Lambda \eta ) \simeq \mathcal{B}(\Lambda _b\rightarrow \Lambda \eta ^\prime )\) , given by the previous study.

Description: We provide a novel action principle for nonrelativistic ideal magnetohydrodynamics in the Eulerian scheme exploiting a Clebsch-type parametrisation. Both Lagrangian and Hamiltonian formulations have been considered. Within the Hamiltonian framework, two complementary approaches have been discussed using Dirac’s constraint analysis. In one case the Hamiltonian is canonical involving only physical variables but the brackets have a noncanonical structure, while the other retains the canonical structure of brackets by enlarging the phase space. The special case of incompressible magnetohydrodynamics is also considered where, again, both the approaches are discussed in the Hamiltonian framework. The conservation of the stress tensor reveals interesting aspects of the theory.