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title: Future constraints on dynamical dark-energy using gravitational-wave standard sirens; abstract: The detection of gravitational waves (GW) by the LIGO and Virgo collaborations offers a whole new range of possible tests and opens up a new window that may shed light on the nature of dark energy and dark matter. In the present work we investigate how future gravitational-wave data could help to constrain different dynamical dark energy models. In particular, we perform cosmological forecastings of a class of well-known and most used dynamical dark energy models using the third-generation gravitational wave detector, the Einstein Telescope. We have considered 1000 simulated GW events in order to constrain the parameter space of the dynamical dark energy models. Our analyses show that the inclusion of the GW data from the Einstein Telescope significantly improves the parameter space of the dynamical dark energy models compared to their constraints extracted from the standard cosmological probes, namely, the cosmic microwave observations, baryon acoustic oscillations distance measurements, supernove type Ia, and the Hubble parameter measurements.

title: Zonostrophic instability driven by discrete particle noise; abstract: The consequences of discrete particle noise for a system possessing a possibly unstable collective mode are discussed. It is argued that a zonostrophic instability (of homogeneous turbulence to the formation of zonal flows) occurs just below the threshold for linear instability. The scenario provides a new interpretation of the random forcing that is ubiquitously invoked in stochastic models such as the second-order cumulant expansion or stochastic structural instability theory; neither intrinsic turbulence nor coupling to extrinsic turbulence is required. A representative calculation of the zonostrophic neutral curve is made for a simple two-field model of toroidal ion-temperature-gradient-driven modes. To the extent that the damping of zonal flows is controlled by the ion–ion collision rate, the point of zonostrophic instability is independent of that rate.

title: Mantle convection and visoelasticity; abstract: The ongoing revolution in the Earth sciences, which began more than twenty years ago, was originally based upon the increasingly widespread acceptance of the idea that continental masses have moved horizontally with respect to one another throughout geological time. This hypothesis of continental \"drift,\" or at least the form of the hypothesis that came to be called seafloor spreading, now serves as the basic paradigm for the organization of most geological and geophysical research. At the center of this guiding principle is the recognition that the solid outer shell of the planet-its iron-magnesium silicate \"mantle,\" which occupies roughly half Earth\u0027s radial extent-must be able to deform as a viscous fluid when it is subjected to an applied shear stress over geological intervals of time. To the extent that this rheological ansatz is correct, it is clear that a thermally induced convective circulation must appear in the mantle in response to a radial temperature gradient that is sufficiently in excess of adiabatic. The observed spreading of the seafloor away from hot mid-oceanic ridges is presumably a surface manifestation of such deep­ seated mantle convection. Likewise, the deep ocean trenches are under­ stood to be regions where cold surface material returns to the mantle to complete the circulation. These and other aspects of the pattern of surface motions associated with mantIe convection have been described kinemati­ cally within the framework of a set of ideas that has come to be called \"plate tectonics.\" The development of this set of ideas has consummated the revolution at a descriptive level and has delivered as its main product a clear view of the velocity field of material at the Earth\u0027s surface at the present epoch of geological time. In so doing, it has also contributed in an

title: Polarization transfer in hyperon decays and its effect in relativistic nuclear collisions; abstract: We calculate the contribution to the polarization of $\\Lambda$ hyperons in relativistic nuclear collisions at high energy from the decays of $\\Sigma^*(1385)$ and $\\Sigma^0$, which are the predominant sources of $\\Lambda$ production besides the primary component, as a function of the $\\Lambda$ momentum. Particularly, we estimate the longitudinal component of the mean spin vector as a function of the azimuthal angle in the transverse plane, assuming that primary $\\Sigma^*$ and $\\Sigma^0$ polarization follow the predictions of local thermodynamic equilibrium in a relativistic fluid. Provided that the rapidity dependence around midrapidity of polarization is negligible, we find that this component of the overall spin vector has a very similar pattern to the primary one. Therefore, we conclude that the secondary decays cannot account for the discrepancy in sign between experimental data and hydrodynamic model predictions of the longitudinal polarization of $\\Lambda$ hyperons recently measured by the STAR experiment at RHIC.

title: A modified lattice Bhatnagar-Gross-Krook model for axisymmetric thermal flow; abstract: Abstract In this paper, a modified lattice Bhatnagar-Gross-Krook (LBGK) model for axisymmetric thermal flow is proposed. In the model, two tunable parameters related to the relaxation times are available by introducing additional gradient terms into the equilibrium functions. By doing so, the values of the dimensionless relaxation times in the LBGK model can be kept in a proper range, and thus the stability of the LBGK model can be improved. Local schemes for the calculation of the additional gradient terms are presented to keep the intrinsic merit of LB. Also, some correction terms are introduced into the evolution function for the temperature field to eliminate the deviation terms exist in the previous LBGK model. Chapman-Enskog analysis demonstrates that the macro equations in the cylindrical coordinates system can be exactly recovered. Numerical tests, including thermal flow in a pipe, thermal Womersley flow and natural convection in a vertical annulus, have been carried out, and the results predicted by the present LBGK model agree well with the existing numerical data. Also, numerical results demonstrate that the present model is superior to the existing LBGK model for axisymmetric thermal flow in term of numerical stability.

title: Table-like magnetocaloric effect in Gd–Ni–Al amorphous/nanocrystalline composites; abstract: In this work, Gd-Ni-Al amorphous/nanocrystalline composites produced by melt-spinning method with double magnetocaloric effect (MCE) plateaus have been developed. Two MCE plateaus, similar to 4.7 J kg(-1) K-1 (90-120 K) and similar to 3.60 J kg(-1) K-1 (250-275 K), were discovered in Gd80Ni11.6Al8.4 for a magnetic field change of 0 to 5 T. For Gd90Ni5.8Al4.2, the plateau values are similar to 3.90 J kg(-1) K-1 (85-120 K) and similar to 6.70 J kg(-1) K-1 (265-280 K) for a magnetic field change of 0-5 T. The reason why MCE plateau formation was investigated and discussed. These composites having two MCE plateaus are competitive candidates for the ideal Ericsson cycle.

title: Polarization and hysteresis in low resistivity ferroelectric composites; abstract: Abstract A compensating technique suitable for measuring the polarization and hysteresis in ferroelectric materials with low resistivity is reported. In this method, three different poling voltages waveforms are successively applied to a sample while the current i, is measured. These are: a sinusoidal, a positively rectified and a negatively rectified sinusoidal voltages. The polarization hysteresis loop is then computed through the integration of the difference between the current obtained during the full sinusoidal voltage loop (i.e. it ) and the sum of the other two currents (i + + i −). In this paper we use this method to determine the remanent polarization and coercive field in a ferroelectric composite of calcium modified lead titanate (PTCa), of a low resistivity formulation, and a copolymer of polyvinylidene fluoride (i.e. P(VDF/TrFE)) as a function of the temperature and field.

title: Numerical and experimental investigation of heat transfer enhancement in a microtube using nanofluids; abstract: Abstract Forced convective laminar flow of different types of nanofluids such as Al2O3 and SiO2, with a nanoparticle size of 30 nm, and different volume fractions ranging from 0.5% to 1% using water as base fluids were investigated numerically and experimentally. This investigation covers the Reynolds number in the range of 90 to 160. The results have shown that SiO2–water nanofluid has the highest Nusselt number, followed by Al2O3–water, and lastly pure water. The maximum heat transfer enhancement was about 22% when using the nanofluids and the numerical and experimental results agree well with the conventional theory.

title: Hubble Space Telescope Photometry of Clusters of Galaxies behind the Dwarf Irregular Galaxies DDO 216 and IC 1613 and the Small Magellanic Cloud; abstract: We have measured the integrated colors of galaxies in clusters located behind the dwarf irregular galaxies DDO 216 (Pegasus) and IC 1613 and a position in the Small Magellanic Cloud (SMC) near the cluster Lindsey 31. We examine limits on the accuracy of using these for studying the total extinction in galaxies. We show that the method is feasible if the data include images through three filters, the distant galaxies are in a cluster (all at nearly the same redshift), the redshift is measured for K-correction, and the cluster has an adequate number of type E/S0 galaxies. It is also beneficial if the cluster extends to late-type galaxies and has sufficient resolution for adequate morphological classification. For DDO 216 and IC 1613, the fit obtained shows no significant reddening, while for the SMC near Lindsey 31 the data are limited, but they show measurable reddening.

title: Testing for gravitationally preferred directions using the lunar orbit.; abstract: As gravity is a long-range force, it is a priori conceivable that the Universe’s global matter distribution selects a preferred rest frame for local gravitational physics. At the post-Newtonian approximation, the phenomenology of preferred-frame effects is described by two parameters a 1 and a 2 , the second of which is already very tightly constrained. Confirming previous suggestions, we show through a detailed Hill-Browntype calculation of a perturbed lunar orbit that lunar laser ranging data have the potential of constraining a 1 at the 10 24 level. It is found that certain retrograde planar orbits exhibit a resonant sensitivity to external perturbations linked to a fixed direction in space. The lunar orbit being quite far from such a resonance exhibits no significant enhancement due to solar tides. Our Hill-Brown analysis is extended to the perturbation linked to a possible differential acceleration toward the galactic center. It is, however, argued that there are strong a priori theoretical constraints on the conceivable magnitude of such an effect. @S0556-2821~96!05912-7#

title: Numerical simulation of energetic electron microsignature drifts at Saturn: Methods and applications; abstract: Abstract Many recent studies show that energetic electron microsignatures are a powerful tool for characterizing key aspects of Saturn’s magnetospheric configuration and dynamics. In all previous investigations, however, analysis of these features was performed through the use of a series of simplifying assumptions (e.g. dipole field model). Furthermore, typical observable parameters of microsignatures (e.g. energy dependent location) have only been discussed qualitatively and a clear understanding about how microsignatures evolve in the magnetosphere is currently lacking. In this study we present a numerical simulation that we developed in order to describe the apparent motion of microsignatures in Saturn’s magnetosphere, under the influence of arbitrary magnetic and electric field models. Our simulations reproduce successfully some typical microsignature properties (energy–time dispersion, high/low lifetime at low/high electron energies). They also indicate how simplifying assumptions used in analytical methods introduce several systematic errors. We demonstrate that, depending on the application and under certain conditions these errors can be neglected, like for instance for small pitch angles and at regions that the dipole approximation is sufficient (inside the orbit of Dione) or for electron energies below few hundred keV. For higher electron energies, systematic errors amplify significantly and existing analytical methods cannot be used. Our model can reconstruct the energy dependent position of microsignatures observed by the MIMI/LEMMS detector with high accuracy, allowing the inference of non-corotational flows (or electric fields) that can be as low as few tens of m s −1 . Since, however the calculation of such flows is indirect, the accuracy of such a determination can be reduced by more than an order of magnitude, if some of these free parameters involved in the simulation cannot be sufficiently constrained. One way to provide such constraints is through inputs (e.g. instantaneous plasma moments) from various Cassini instruments and updated magnetospheric field models. In that case, microsignature analysis may prove to be one of the best methods for attempting to measure or to at least constrain the magnitude of the very slow and global plasma outflow in Saturn’s magnetosphere that is driven by mass loading at Enceladus.

title: Symmetric and asymmetric light dark matter; abstract: to DM ratio to be less than ∼ 2 × 10 −6 (10 −1 ) for DM mass mX = 1 MeV (10 GeV) with ionizing efficiency factorf ∼ 1. We determine the minimum annihilation cross section for achieving these asymmetries subject to the relic density constraint; these cross sections are larger than the usual thermal annihilation cross section. On account of collider constraints, such annihilation cross sections can only be obtained by invoking light mediators. These light mediators can give rise to significant DM self-interactions, and we derive a lower bound on the mediator mass from elliptical DM halo shape constraints. We find that halo shapes require a mediator with mass m� \u0026 4 × 10 −2 MeV (40 MeV) for mX =1 MeV (10 GeV). We map all of these constraints to the parameter space of DM-electron and DM-nucleon scattering cross sections for direct detection. For DM-electron scattering, a significant fraction of the parameter space is already ruled out by beam-dump and supernova cooling constraints.

title: Spherically symmetric brane in a bulk of f(R) and Gauss-Bonnet Gravity; abstract: Effective gravitational field equations on a four dimensional brane embedded in a five dimensional bulk have been considered. Using the Einstein-Hilbert action along with the Gauss-Bonnet correction term, we have derived static spherically symmetric vacuum solution to the effective field equations, first order in the Gauss-Bonnet coupling parameter. The solution so obtained, has one part corresponding to general relativity with an additional correction term, proportional to the Gauss-Bonnet coupling parameter. The correction term modifies the spacetime structure, in particular, the location of the event horizon. Proceeding further, we have derived effective field equations for $f(R)$ gravity with Gauss-Bonnet correction term and a static spherically symmetric solution has been obtained. In this case the Gauss-Bonnet term modifies both the event and cosmological horizon of the spacetime. There exist another way of obtaining the brane metric --- expanding the bulk gravitational field equations in the ratio of bulk to brane curvature scale and assuming a separable bulk metric ansatz. It turns out that static, spherically symmetric solutions obtained from this perturbative method can be matched exactly, with the solutions derived earlier. This will hold for Einstein-Hilbert plus Gauss-Bonnet as well as for f(R) with the Gauss-Bonnet correction. Implications of these results are discussed.

title: The variation in molecular gas depletion time among nearby galaxies: what are the main parameter dependences?; abstract: We re-analyze correlations between global molecular gas depletion time (tdep) and galaxy parameters including stellar mass, specific star formation rate, stellar surface density and concentration index. The analysis is based on the COLD GASS survey, which includes galaxies with stellar masses in the range 10 10 – 10 11.5 M ⊙ with molecular gas mass estimates derived from CO(J=1-0) line measurements. We improve on previous work by Saintonge et al (2011b) by estimating star formation rates using the combination of GALEX FUV and WISE 22 µm data and by deriving tdep within a fixed aperture set by the IRAM beam size. In our new study we find correlations with much smaller scatter. Dependences of the depletion time on galaxy structural parameters such as stellar surface density and concentration index are now weak or absent. Differences with previous work arise because dust extinction as measured by the ratio of 22 micron to far-UV flux in the galaxy, correlates strongly with galaxy structural parameters. We further demonstrate that the primary global parameter correlation is between tdep and sSFR; all other remaining correlations can be shown to be induced by this primary dependence. This implies that galaxies with high current-topast-averaged star formation activity, will drain their molecular gas reservoir sooner. We then analyze molecular gas depletion times on 1-kpc scales in galactic disks using data from the HERACLES survey. There is remarkably good agreement between the global tdep versus sSFR relation for the COLD GASS galaxies and that derived for 1 kpc scale grid regions in disks. The strong correlation between tdep and sSFR extends continuously over a factor of 10 in tdep from log SFR/M� = −11.5 to −9, i.e. from nearly quiescent patches of the disk to disk regions with very strong star formation. This leads to the conclusion that the local molecular gas depletion time in galactic disks is dependent on the local fraction of young-to-old stars.

title: Strange quark matter fragmentation in astrophysical events; abstract: Abstract The conjecture of Bodmer–Witten–Terazawa suggesting a form of quark matter (Strange Quark Matter) as the ground state of hadronic interactions has been studied in laboratory and astrophysical contexts by a large number of authors. If strange stars exist, some violent events involving these compact objects, such as mergers and even their formation process, might eject some strange matter into the interstellar medium that could be detected as a trace signal in the cosmic ray flux. To evaluate this possibility, it is necessary to understand how this matter in bulk would fragment in the form of strangelets (small lumps of strange quark matter in which finite effects become important). We calculate the mass distribution outcome using the statistical multifragmentation model and point out several caveats affecting it. In particular, the possibility that strangelets fragmentation will render a tiny fraction of contamination in the cosmic ray flux is discussed.

title: Joint Wigner distribution for spin-1/2 particles; abstract: The Wigner distribution has proven to be a useful tool in many quantum problems requiring a joint distribution of position and momentum. In the present paper we develop a joint distribution for spin components within the spirit of the Wigner distribution. This distribution provides an insight into the quantum theory of measurement. We also discuss how one may write joint distributions for two arbitrary noncommuting operators.

title: Subfilter-scale enrichment of planetary boundary layer large eddy simulation using discrete Fourier-Gabor modes; abstract: A new multiscale simulation methodology is introduced to facilitate computationally efficient simulations of high Reynolds number turbulence seen in wall-bounded flows. The scale splitting methodology uses traditional large eddy simulation (LES) with a wall model to simulate the larger scales which are subsequently enriched using a space–time compatible kinematic simulation. Computational feasibility and robustness of the methodology are investigated using two idealized problems that emulate turbulence within the planetary boundary layer (PBL), and a finite Reynolds number channel flow problem which serves to validate the methodology against direct numerical simulation. The space–time correlations and spectra generated using enriched LES show excellent agreement with LES conducted at high resolution for all three problems; thereby demonstrating the potential of this approach for high resolution PBL simulations with a drastic reduction in the computational costs when compared to the conventional approach.

title: Enhanced piezoelectricity and nature of electric-field induced structural phase transformation in textured lead-free piezoelectric Na0.5Bi0.5TiO3-BaTiO3 ceramics; abstract: This letter provides a comparative description of the properties of textured and randomly oriented poly-crystalline lead-free piezoelectric 0.93(Na0.5Bi0.5TiO3)-0.07BaTiO3 (NBT-BT) ceramics. A high longitudinal piezoelectric constant of (d33) ∼ 322 pC/N was obtained in (001)PC textured NBT-7BT ceramics, which is almost ∼2× times the d33 coefficient reported for randomly oriented ceramics of the same composition. In situ neutron diffraction experiments revealed that characteristically different structural responses are induced in textured and randomly oriented NBT-BT ceramics upon application of electric fields (E), which are likely related to the varying coherence lengths of polar nanoregions and internal stresses induced by domain switching.

title: THE LYMAN ALPHA MORPHOLOGY OF LOCAL STARBURST GALAXIES: RELEASE OF CALIBRATED IMAGES; abstract: We present reduced and calibrated high resolution Lyman-alpha (Lyα) images for a sample of six local star-forming galaxies. Targets were selected to represent a range in luminosity and metallicity ...

title: NLO QCD corrections to off-shell top-antitop production with leptonic decays at hadron colliders; abstract: We present details of a calculation of the cross section for hadronic top–antitop production in next-to-leading order (NLO) QCD, including the decays of the top and antitop into bottom quarks and leptons. This calculation is based on matrix elements for νee + � − ¯ ν�b ¯ production and includes all non-resonant diagrams, interferences, and off-shell effects of the top quarks. Such contributions are formally suppressed by the top-quark width and turn out to be small in the inclusive cross section. However, they can be strongly enhanced in exclusive observables that play an important role in Higgs and new-physics searches. Also non-resonant and off-shell effects due to the finite W-boson width are investigated in detail, but their impact is much smaller than naively expected. We also introduce a matching approach to improve NLO calculations involving intermediate unstable particles. Using a fixed QCD scale leads to perturbative instabilities in the high-energy tails of distributions, but an appropriate dynamical scale stabilises NLO predictions. Numerical results for the total cross section, several distributions, and asymmetries are presented for Tevatron and the LHC at 7TeV, 8TeV, and 14TeV.

title: Structural and optical properties of epitaxial BaTiO3 thin films grown on GdScO3(110).; abstract: We have prepared 1-μm-thick epitaxial BaTiO3 thin films on GdScO3(110) using pulsed laser deposition. The structural perfection of the films was revealed by a rocking curve width of Δω=0.13° for the 002 BaTiO3 reflection and a Rutherford backscattering spectrometry/channeling minimum yield, χmin, of 0.5% measured for the Ba signal behind the surface peak. High-resolution transmission electron microscopy revealed an epitaxial relationship between BaTiO3 and GdScO3 and a sharp interface between the substrate and the film. The refractive index of the BaTiO3 film was no=2.329±0.002 and ne=2.307±0.002 at a wavelength of 632.8 nm and no=2.248±0.002 and ne=2.228±0.002 at a wavelength of 1523 nm. The optical losses were less than 2 dB/cm at a wavelength of 632.8 nm.

title: Traversable wormholes: Some simple examples; abstract: Building on the work of Morris, Thorne, and Yurtsever, some particularly simple examples of traversable wormholes are exhibited. These examples are notable both because the analysis is not limited to spherically symmetric cases, and because it is possible to in some sense minimize the use of exotic matter. In particular, it is possible for a traveller to traverse such a wormhole without passing through a region of exotic matter. As in previous analyses, the weak energy condition is violated in these traversable wormholes.

title: Absorption and dispersion control in a five-level M-type atomic system; abstract: We investigate the steady optical response of a coherently driven five-level M-type atomic system in three different situations. When all three coupling fields have the same zero detuning, we just find one deep transparency window accompanied by a steep normal dispersion in the probe absorption and dispersion spectra. When two coupling fields are detuned from the relevant transitions to the same extent, however, a second deep transparency window may be observed in the presence of a narrow absorption line of linewidth ~ 50 kHz. In this case, two single-photon far-detuned transitions can be replaced by a two-photon resonant transition, so the five-level M system in fact reduces into a four-level quasi-? system. Finally, we note that no deep transparency windows and no narrow absorption lines can be found when all three coupling fields have unequal detunings.

title: Positronium Portal into Hidden Sector: A new Experiment to Search for Mirror Dark Matter; abstract: The understanding of the origin of dark matter has great importance for cosmology and particle physics. Several interesting extensions of the standard model dealing with solution of this problem motivate the concept of hidden sectors consisting of SU(3)xSU(2)_LxU(1)_Y singlet fields. Among these models, the mirror matter model is certainly one of the most interesting. The model explains the origin of parity violation in weak interactions, it could also explain the baryon asymmetry of the Universe and provide a natural ground for the explanation of dark matter. The mirror matter could have a portal to our world through photon-mirror photon mixing (epsilon). This mixing would lead to orthopositronium (o-Ps) to mirror orthopositronium oscillations, the experimental signature of which is the apparently invisible decay of o-Ps. In this paper, we describe an experiment to search for the decay o-Ps -\u003e invisible in vacuum by using a pulsed slow positron beam and a massive 4pi BGO crystal calorimeter. The developed high efficiency positron tagging system, the low calorimeter energy threshold and high hermiticity allow the expected sensitivity in mixing strength to be epsilon about 10^-9, which is more than one order of magnitude below the current Big Bang Nucleosynthesis limit and in a region of parameter space of great theoretical and phenomenological interest. The vacuum experiment with such sensitivity is particularly timely in light of the recent DAMA/LIBRA observations of the annual modulation signal consistent with a mirror type dark matter interpretation.

title: The onset of instability in a horizontal fluid layer due to a step change in temperature; abstract: Abstract The onset of instability in a fluid layer which is subjected to a sudden change in surface temperature is analysed by a modified version of the frozen time hypothesis. The assumption that for large Prandtl number the temperature disturbances are confined to the effective thermal depth leads to a considerable simplification in the formulation of the stability problem. The effect of the Rayleigh number on the onset time is discussed and clearly explained. The relation between the Rayleigh number and the wavenumber predicted here agrees remarkably well with the extant amplification theory.

title: Updated measurement of the tau lepton lifetime; abstract: A new measurement of the mean lifetime of the τ lepton is presented. Three different analysis methods are applied to a sample of 90 000 τ pairs, collected in 1993 and 1994 with the ALEPH detector at LEP. The average of this measurement and those previously published by ALEPH is ττ = 290.1 ± 1.5 ± 1.1 fs.

title: Exact solution of the neutralino mass matrix; abstract: The eigenvalue problem for the neutralino mass matrix has been solved exactly and the eigenvalues are expressed in terms of thev1/v2, chargino and gluino masses which are directly measurable. An analytical formula for the lightest neutralino mass as a function of the above parameters is obtained. Formulae for the photino, zino and neutral higgsino contents of each of the physical neutralino mass eigenstates states have been found. Taking into account these formulae it has been possible to predict the upper (lower) bound on the mass of zino (photino) dominant neutralino states, including the lightest one. The neutralino-gluino and neutralino-chargino mass planes have also been constrained by using the latest LEP data.

title: Measurement of charged pions in 12C + 12C collisions at 1 A GeV and 2 A GeV with HADES; abstract: We present the results of a study of charged-pion production in 12C + 12C collisions at incident beam energies of 1A GeV and 2A GeV using the HADES spectrometer at GSI. The main emphasis of the HADES program is on the dielectron signal from the early phase of the collision. Here, however, we discuss the data with respect to the emission of charged hadrons, specifically the production of \\( \\pi^{{\\pm}}_{}\\) mesons, which are related to neutral pions representing a dominant contribution to the dielectron yield. We have performed the first large-angular-range measurement of the distribution of \\( \\pi^{{\\pm}}_{}\\) mesons for the 12C + 12C collision system covering a fairly large rapidity interval. The pion yields, transverse-mass and angular distributions are compared with calculations done within a transport model, as well as with existing data from other experiments. The anisotropy of pion production is systematically analyzed.

title: The measurement of R at CLEO; abstract: Measurements of the total cross section of e + e − → hadrons are presented in two different ranges of centre-of-mass energy. The measurements are made using the CLEO III and CLEO-c detectors at the Cornell Electron Storage Ring. The absolute cross sections and the values of R, the ratio of hadronic to muon pair production cross sections, are determined at seven centre-of-mass energies between 6.964 and 10.538 GeV. The total cross sections and values of R are also determined at thirteen centre-of-mass energies between 3.97 and 4.26 GeV; in addition, the inclusive and exclusive cross sections for D + , D 0 and D s + production are presented. Furthermore, for the lower centre-of-mass energy range, exclusive cross-sections are presented for final states consisting of two charm mesons: D D ¯ , D ∗ D ¯ , D D ∗ ¯ , D ∗ D ∗ ¯ , D s + D s − , D s ∗ + D s − , D s + D s ∗ − , D D ¯ ∗ π and D ∗ D ¯ ∗ π .

title: Magneto-Optic Modulation of a Light Beam in Sodium Vapor*; abstract: The enhanced Faraday effect in gases for optical frequencies near absorption lines provides a basis for modulating a light beam. In the present study, incident radiation consisting of the Zeeman s components of the D lines of sodium passed through a polarizer to the Faraday cell, which employed saturated sodium vapor at approximately 240°C as an optical medium. Rotation of the plane of polarization of radiation traversing the cell was modulated at frequencies as high as 698 Mc/sec. On the basis of cw modulation studies, there appears to be no reduction in the integrated time-varying Faraday effect for frequencies as high as 265 Mc/sec; this frequency is 1100 times the Larmor frequency in the magnetic fields involved and 26 times the natural linewidth. There was no evidence of any reduction in frequency response for pulsed modulation at 698 Mc/sec.

title: Quantum-Spacetime Phenomenology; abstract: I review the current status of phenomenological programs inspired by quantum-spacetime research. I stress in particular the significance of results establishing that certain data analyses provide sensitivity to effects introduced genuinely at the Planck scale. My main focus is on phenomenological programs that affect the directions taken by studies of quantum-spacetime theories.

title: The Shortest-Known–Period Star Orbiting Our Galaxy’s Supermassive Black Hole; abstract: Stars with short orbital periods at the center of our Galaxy offer a powerful probe of a supermassive black hole. Over the past 17 years, the W. M. Keck Observatory has been used to image the galactic center at the highest angular resolution possible today. By adding to this data set and advancing methodologies, we have detected S0-102, a star orbiting our Galaxy’s supermassive black hole with a period of just 11.5 years. S0-102 doubles the number of known stars with full phase coverage and periods of less than 20 years. It thereby provides the opportunity, with future measurements, to resolve degeneracies in the parameters describing the central gravitational potential and to test Einstein’s theory of general relativity in an unexplored regime.

title: Spectral interactions of rapidly-rotating anisotropic turbulent viscous and thermal diffusion in the Earth’s core; abstract: Abstract Rapidly-rotating anisotropic turbulence in the Earth’s core is modelled by the viscous and thermal diffusion tensors, D ν ≔2ρν 0 I +ρν ΩΩ ΩΩ and D κ ≔κ 0 I +κ ΩΩ ΩΩ , where I is the unit tensor, Ω is the angular velocity and the coefficients ν ΩΩ and κ ΩΩ are spherically-symmetric. Toroidal–poloidal spectral interactions are derived for the anisotropic parts of the body forces associated with the mean anisotropic viscous stress tensor, D ν ·(∇ v ) S and with its symmetric part. The stress tensors are linear in the trace-free symmetric part of the velocity gradient. Techniques of vector and tensor spherical harmonic analysis are used to find the vector spherical harmonic components of the body forces. From these components the toroidal–poloidal field interactions, (ΩΩtt n ) , (ΩΩst n ) , (ΩΩts n ) , (ΩΩss n ) , (ΩtΩt n ) , (ΩsΩt n ) , (ΩtΩs n ) and (ΩsΩs n ) , of the toroidal ( t n ) and poloidal ( s n ) momentum equations are derived using computer algebra. The temperature spectral interactions are also derived for the mean heat flux given by the turbulent thermal diffusion tensor. These spectral interactions represent a computationally practical first step in incorporating anisotropic turbulence models into existing dynamically-consistent angular–spectral geodynamo codes.

title: Interpretation of S-state ion E.P.R. spectra; abstract: Abstract Although a considerable body of data exists on the parametrization of the ground-state splittings of S-state ions in crystals, relatively little progress has been made in obtaining a quantitative understanding of the mechanisms which determine these parameters. In the course of summarizing our present understanding, we emphasize the need for making planned experiments explicitly aimed at testing theoretical models, such as those proposed in this article. The variable frequency E.P.R. technique is described in some detail, as it has proved to be particularly useful in this respect.

title: Phase lags of quasi-periodic oscillations across source states in the low-mass X-ray binary 4U 1636–53; abstract: While there are many dynamical mechanisms and models that try to explain the origin and phenomenology of the quasi-periodic oscillations (QPOs) seen in the X-ray light curves of low-mass X-ray binaries, few of them address how the radiative processes occurring in these extreme environments give rise to the rich set of variability features actually observed in these light curves. A step towards this end comes from the study of the energy and frequency dependence of the phase lags of these QPOs. Here we used a methodology that allowed us to study, for the first time, the dependence of the phase lags of all QPOs in the range of 1-1300 Hz detected in the low-mass X-ray binary 4U 1636-53 upon energy and frequency as the source changes its states as it moves through the colour-colour diagram. Our results suggest that within the context of models of up-scattering Comptonization, the phase lags dependences upon frequency and energy can be used to extract size scales and physical conditions of the medium that produces the lags.

title: Probing the neutrino mass hierarchy with cosmic microwave background weak lensing; abstract: We forecast constraints on cosmological parameters with primary cosmic microwave background (CMB) anisotropy information and weak lensing reconstruction with a future post-Planck CMB experiment, the Cosmic Origins Explorer (COrE), using oscillation data on the neutrino mass splittings as prior information. Our Markov chain Monte Carlo (MCMC) simulations in flat models with a non-evolving equation of state of dark energy w give typical 68 per cent upper bounds on the total neutrino mass of 0.136 and 0.098 eV for the inverted and normal hierarchies, respectively, assuming the total summed mass is close to the minimum allowed by the oscillation data for the respective hierarchies (0.10 and 0.06 eV). Including geometric information from future baryon acoustic oscillation measurements with the complete Baryon Oscillation Spectroscopic Survey, Type Ia supernovae distance moduli from Wide-Field Infrared Survey Telescope (WFIRST) and a realistic prior on the Hubble constant, these upper limits shrink to 0.118 and 0.080 eV for the inverted and normal hierarchies, respectively. Addition of these distance priors also yields per cent-level constraints on w. We find tension between our MCMC results and the results of a Fisher matrix analysis, most likely due to a strong geometric degeneracy between the total neutrino mass, the Hubble constant and w in the unlensed CMB power spectra. If the minimal-mass, normal hierarchy were realized in nature, the inverted hierarchy should be disfavoured by the full data combination at typically greater than the 2σ level. For the minimal-mass inverted hierarchy, we compute the Bayes factor between the two hierarchies for various combinations of our forecast data sets, and find that the future cosmological probes considered here should be able to provide ‘strong’ evidence (odds ratio 12:1) for the inverted hierarchy. Finally, we consider potential biases of the other cosmological parameters from assuming the wrong hierarchy and find that all biases on the parameters are below their 1σ marginalized errors.

title: A photometric study of chemically peculiar stars with the STEREO satellites - I. Magnetic chemically peculiar stars; abstract: About 10 per cent of upper main-sequence stars are characterized by the presence of chemical peculiarities, often found together with a structured magnetic field. The atmospheres of most of those chemically peculiar stars present surface spots, leading to photometric variability caused by rotational modulation. The study of the light curves of those stars therefore permits a precise measurement of their rotational period, which is important to study stellar evolution and to plan further detailed observations. We analysed the light curves of 1028 chemically peculiar stars obtained with the STEREO spacecraft. We present here the results obtained for the 337 magnetic chemically peculiar stars in our sample. Thanks to the cadence and stability of the photometry, STEREO data are perfectly suitable to study variability signals with a periodicity typical of magnetic chemically peculiar stars. Using a matched filter algorithm and then two different period searching algorithms, we compiled a list of 82 magnetic chemically peculiar stars for which we measured a reliable rotational period; for 48 of them, this is the first measurement of their rotational period. The remaining 255 stars are likely to be constant, although we cannot exclude the presence of long-period variability. In some cases, the presence of blending or systematic effects prevented us from detecting any reliable variability and in those cases we classified the star as constant. For each star we classified as variable, we determined temperature, luminosity, mass and fractional age, but the limited statistics, biased towards the shorter periods, prevented us from finding any evolutionary trend of the rotational period. For a few stars, the comparison between their projected rotational velocity and equatorial velocity let us believe that their real rotational period might be longer than that found here and previously obtained. For the 82 stars identified as variable, we give all necessary information needed to plan further phase-dependent observations.

title: Thermal Decomposition Mechanism of N2-Impurity Helium Solids; abstract: The mechanism for the thermal decomposition of N 2 containing impurity helium solids (IHS) in superfluid 4 He is reported. We show that the solid undergoes rapid thermal annealing leading to mobilization of the nitrogen atoms. Subsequently, the nitrogen atoms form molecular N 2 excimers, which are mobile in the solid and are responsible for various emission bands observed over the thermal decomposition of IHS. The present interpretation of the spectroscopic results indicates that IHS contains only ground state atomic species.

title: Phase diagram of chiral quark matter: From weakly to strongly coupled Fulde-Ferrell phase; abstract: We calculate the phase diagram of two-flavor quark matter within the Nambu-Jona-Lasinio (NJL) model in the temperature-flavor asymmetry plane in the case where there are three competing phases: the homogeneous Bardeen-Cooper-Schrieffer (BCS) phase, the unpaired phase, and a phase with broken spatial symmetry, which is here taken to be the counterpart of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase in condensed matter physics. The system belongs to the universality class of paramagnetic-ferromagnetic-helical systems, and therefore contains a tricritical Lifshitz point in its phase diagram, where the momentum scale characterizing the breaking of translational invariance has a critical exponent of 1/2 to leading order. Upon varying the coupling constant of the theory we find that in weak coupling, the FFLO phase is favored at arbitrary flavor asymmetries for sufficiently low temperatures; at intermediate coupling its occupancy domain is shifted towards larger asymmetries. Strong coupling features a new regime of an inhomogeneous FF state, which we identify with a current-carrying Bose-Einstein condensate of tightly bound up and down quarks. The temperature and asymmetry dependence of the gap function is studied. It is shown that the anomalous temperature dependence of the gap in the homogeneous, flavor-asymmetric phase is transformed into a normal dependence (self-similar to themore » BCS phase) at arbitrary coupling, once the FF phase is allowed for. We analyze the occupation numbers and the Cooper-pair wave function and show that when the condensate momentum is orthogonal to the particle momentum the minority component contains a blocking region (breach) around the Fermi sphere in the weak-coupling limit, which engulfs more low-momentum modes as the coupling is increased, and eventually leads to a topological change in strong coupling, where the minority Fermi sphere contains either two occupied strips or an empty sphere. For nonorthogonal momenta, the blocking region is either reduced or extinct, i.e., no topological changes are observed.« less

title: Grain-boundary magnetoresistance enhancement induced by network self-optimization; abstract: A random conductance network model is proposed to study the global magnetoresistance effects of granular systems of half-metallic oxides. Different transport mechanisms resulting from grain-boundary effects are considered and their contributions to the total magnetoresistance of the network are discussed. It is found that magnetoresistance can be enhanced obviously when the spatial current localization is large enough to produce a percolative conductance path along conductances of high magnetoresistance in the network.

title: Influence of mechanical properties of piezoceramics on transverse sensitivity—An important factor in construction of accelerometers; abstract: Abstract Piezoceramics used in accelerometers are usually chosen because of their high charge or voltage sensitivity, stable temperature curve and low aging rate. Transverse sensitivity is a rather disturbing factor and can be diminished by special construction and careful mounting. Although primarily of interest regarding manufactur of accelerometers, dependence between mechanical properties of piezoceramics and transverse sensitivity has not been systematically tested. This report is based on several tests accomplished by means of commercial available accelerometers. Results indicate whether the right choice of ceramics can improve the quality of accelerometers.

title: Evidence for a narrow dip structure at 1.9 GeV/c2 in 3π+3π− diffractive photoproduction; abstract: Abstract A narrow dip structure has been observed at 1.9 GeV/ c 2 in a study of diffractive photoproduction of the 3 π + 3 π − final state performed by the Fermilab experiment E687.

title: Doping and bond length contributions to Mn K-edge shift in La 1−x Sr x MnO 3 (x=0-0.7) and their correlation with electrical transport properties; abstract: The room temperature experimental Mn K-edge X-ray absorption spectra of La1 − x Sr x MnO3 (x = 0−0.7) are compared with the band structure calculations using spin polarized density functional theory. It is explicitly shown that the observed shift in the energy of Mn K-edge on substitution of divalent Sr on trivalent La sites corresponds to the shift in the center of gravity of the unoccupied Mn 4p-band contributing to the Mn K-absorption edge region. This correspondence is then used to separate the doping and size contributions to the edge shift due to variation in the number of electrons in valence band and Mn-O bond lengths, respectively, when Sr is doped into LaMnO3. Such separation is helpful to find the localization behaviour of charge carriers and to understand the observed transport properties of these compounds.

title: Relation between the 16O(α, γ)20Ne reaction and its reverse 20Ne(γ, α)16O reaction in stars and in the laboratory; abstract: The astrophysical reaction rates of the 16O(α, γ)20Ne capture reaction and its inverse 20Ne(γ, α)16O photodisintegration reaction are given by the sum of several narrow resonances and a small direct capture contribution at low temperatures. Although the thermal population of low-lying excited states in 16O and 20Ne is extremely small, the first excited state in 20Ne plays a non-negligible role for the photodisintegration rate. Consequences for experiments with so-called quasi-thermal photon energy distributions are discussed.

title: Domain Processes in Lead Titanate Zirconate and Barium Titanate Ceramics; abstract: The amount of 90° reorientation during poling was determined from mechanical strains measured during the poling process. With tetragonal lead titanate zirconate 53% of the possible 90° reorientation occurred during poling, but this figure dropped to 44% upon removal of the poling field. With barium titanate the figures are only 17% and 12%, respectively. Comparison of the polarization of poled polycrystalline barium titanate with that for single crystals indicates that 180° reorientation is virtually perfect. Application of very high compressive stress parallel to the polar axis causes 90° switching of nearly all aligned domains, and, therefore, removes virtually all polarization. Curves of released charge as function of mechanical strain are nearly linear, but curves of released charge as function of stress are strongly nonlinear. Application of high compressive stress perpendicular to the polar axis also causes 90° domain reorientation and a reduction in the total polarization of the ceramic. This domai...

title: Before primordial inflation; abstract: Abstract We show that, before the onset of primordial inflation, there is plenty of time for fields with very flat potentials and very weak couplings (such as the local supersymmetry breaking field and the axion field) to roll to the global minima of their potentials. Thus there is no energy stored in these fields today and hence no constraint (such as f axion 12 GeV) on the properties of their potentials.

title: Controllable steep dispersion with gain in a four-level N-scheme with four-wave mixing; abstract: We present a theoretical analysis of the propagation of light pulses through a medium of four-level atoms, with two strong pump fields and a weak probe field in an N-scheme arrangement. We show that four-wave mixing has a profound effect on the probe-field group velocity and absorption, allowing the probe-field propagation to be tuned from superluminal to slow-light regimes with amplification.

title: Stable black holes in shift-symmetric Horndeski theories; abstract: In shift-symmetric Horndeski theories, a static and spherically symmetric black hole can support linearly time-dependent scalar hair. However, it was shown that such a solution generically suffers from ghost or gradient instability in the vicinity of the horizon. In the present paper, we explore the possibility to avoid the instability, and present a new example of theory and its black hole solution with a linearly time-dependent scalar configuration. We also discuss the stability of solutions with static scalar hair for a special case where nonminimal derivative coupling to the Einstein tensor appears.

title: On the basic mechanism of Pixelized Photon Detectors; abstract: A Pixelized Photon Detector (PPD) is a generic name for the semiconductor devices operated in the Geiger-mode, such as Silicon PhotoMultiplier and Multi-Pixel Photon Counter, which has high photon counting capability. While the internal mechanisms of the PPD have been intensively studied in recent years, the existing models do not include the avalanche process. We have simulated the multiplication and quenching of the avalanche process and have succeeded in reproducing the output waveform of the PPD. Furthermore our model predicts the existence of dead-time in the PPD which has never been numerically predicted. For searching the dead-time, we also have developed waveform analysis method using deconvolution which has the potential to distinguish neighboring pulses precisely. In this paper, we discuss our improved model and waveform analysis method.

title: Shock waves in strongly coupled plasmas; abstract: Shock waves are supersonic disturbances propagating in a fluid and giving rise to dissipation and drag. Weak shocks, i.e., those of small amplitude, can be well described within the hydrodynamic approximation. On the other hand, strong shocks are discontinuous within hydrodynamics and therefore probe the microscopics of the theory. In this paper, we consider the case of the strongly coupled N=4 plasma whose microscopic description, applicable for scales smaller than the inverse temperature, is given in terms of gravity in an asymptotically AdS{sub 5} space. In the gravity approximation, weak and strong shocks should be described by smooth metrics with no discontinuities. For weak shocks, we find the dual metric in a derivative expansion, and for strong shocks we use linearized gravity to find the exponential tail that determines the width of the shock. In particular, we find that, when the velocity of the fluid relative to the shock approaches the speed of light v{yields}1 the penetration depth l scales as l{approx}(1-v{sup 2}){sup 1/4}. We compare the results with second-order hydrodynamics and the Israel-Stewart approximation. Although they all agree in the hydrodynamic regime of weak shocks, we show that there is not even qualitative agreement for strong shocks. For themore » gravity side, the existence of shock waves implies that there are disturbances of constant shape propagating on the horizon of the dual black holes.« less

title: Suppressed Coherence due to Orbital Correlations in the Ferromagnetically Ordered Metallic Phase of Mn Compounds; abstract: Small Drude weight D together with small specific heat coefficient γ observed in the ferromagnetic phase of R 1- x A x MnO 3 (R=La, Pr, Nd, Sm; A=Ca, Sr, Ba) are analyzed in terms of a proximity effect of the Mott insulator. The scaling theory for the metal-insulator transition with the critical enhancement of orbital correlations toward the staggered ordering of two e g orbitals such as 3 x 2 - r 2 and 3 y 2 - r 2 symmetries may lead to the critical exponents of D ∝δ u and γ∝δ v with u =3/2 and v =0. The result agrees with the experimental indications.

title: Evolution of spherical overdensities in holographic dark energy models; abstract: In this work we investigate the spherical collapse model in flat FRW dark energy universes. We consider the Holographic Dark Energy (HDE) model as a dynamical dark energy scenario with a slowly time-varying equation-of-state (EoS) parameter $w_{\\rm de}$ in order to evaluate the effects of the dark energy component on structure formation in the universe. We first calculate the evolution of density perturbations in the linear regime for both phantom and quintessence behavior of the HDE model and compare the results with standard Einstein-de Sitter (EdS) and $\\Lambda$CDM models. We then calculate the evolution of two characterizing parameters in the spherical collapse model, i.e., the linear density threshold $\\delta_{\\rm c}$ and the virial overdensity parameter $\\Delta_{\\rm vir}$. We show that in HDE cosmologies the growth factor $g(a)$ and the linear overdensity parameter $\\delta_{\\rm c}$ fall behind the values for a $\\Lambda$CDM universe while the virial overdensity $\\Delta_{\\rm vir}$ is larger in HDE models than in the $\\Lambda$CDM model. We also show that the ratio between the radius of the spherical perturbations at the virialization and turn-around time is smaller in HDE cosmologies than that predicted in a $\\Lambda$CDM universe. Hence the growth of structures starts earlier in HDE models than in $\\Lambda$CDM cosmologies and more concentrated objects can form in this case. It has been shown that the non-vanishing surface pressure leads to smaller virial radius and larger virial overdensity $\\Delta_{\\rm vir}$. We compare the predicted number of halos in HDE cosmologies and find out that in general this value is smaller than for $\\Lambda$CDM models at higher redshifts and we compare different mass function prescriptions. Finally, we compare the results of the HDE models with observations.

title: The Dependence on Environment of the Color-Magnitude Relation of Galaxies; abstract: The distribution in color and absolute magnitude is presented for 55,158 galaxies taken from the Sloan Digital Sky Survey in the redshift range 0.08 \u003c z \u003c 0.12, as a function of the galaxy number overdensity in a cylinder of transverse radius 1 h-1 Mpc and line-of-sight half-length 8 h-1 Mpc. In all environments, bulge-dominated galaxies (defined to be those with radial profiles best fitted with large S?rsic indices) have a color-magnitude diagram dominated by red galaxies for which the mode of the color distribution at fixed absolute magnitude depends linearly on absolute magnitude. Although the most luminous galaxies reside preferentially in high-density regions and blue galaxies reside preferentially in low-density regions, there is only a barely detectable variation with overdensity in the color (zero point) or slope of the linear relation between the mode color and luminosity [\u003c0.02 mag in 0.1 or (B-V)]. These results constrain variations with environmental density in the ages or metallicities of typical bulge-dominated galaxies to be under 20%.

title: Fundamental properties of stars using asteroseismology from Kepler and CoRoT and interferometry from the CHARA Array; abstract: We present results of a long-baseline interferometry campaign using the PAVO beam combiner at the CHARA Array to measure the angular sizes of five main-sequence stars, one subgiant and four red giant stars for which solar-like oscillations have been detected by either Kepler or CoRoT. By combining interferometric angular diameters, Hipparcos parallaxes, asteroseismic densities, bolometric fluxes, and high-resolution spectroscopy, we derive a full set of near-model-independent fundamental properties for the sample. We first use these properties to test asteroseismic scaling relations for the frequency of maximum power (?max) and the large frequency separation (??). We find excellent agreement within the observational uncertainties, and empirically show that simple estimates of asteroseismic radii for main-sequence stars are accurate to 4%. We furthermore find good agreement of our measured effective temperatures with spectroscopic and photometric estimates with mean deviations for stars between T eff = 4600-6200 K of ?22 ? 32 K (with a scatter of 97?K) and ?58 ? 31 K (with a scatter of 93?K), respectively. Finally, we present a first comparison with evolutionary models, and find differences between observed and theoretical properties for the metal-rich main-sequence star HD?173701. We conclude that the constraints presented in this study will have strong potential for testing stellar model physics, in particular when combined with detailed modeling of individual oscillation frequencies.

title: The Galactic Halo Magnetic Field Revisited; abstract: Recently, Sun et al. published new Galactic 3D-models of magnetic fields in the disk and halo of the Milky Way and the distribution of cosmic-ray electron density by taking into account the thermal electron density model NE2001 by Cordes \u0026 Lazio. The models successfully reproduce observed continuum and polarization all-sky maps and the distribution of rotation measures of extragalactic sources across the sky. However, the model parameters obtained for the Galactic halo, although reproducing the observations, seem physically unreasonable: the magnetic field needs to be significantly stronger in the Galactic halo than in the plane and the cosmic-ray distribution must be truncated at about 1 kpc to avoid excessive synchrotron emission from the halo. The reason for these unrealistic parameters was the low scale-height of the warm thermal gas of about 1 kpc adopted in the NE2001 model. However, this scale-height seemed reasonable and was well studied by numerous investigations. Recently, the scale-height of the warm gas in the Galaxy was revised by Gaensler et al. to about 1.8 kpc, by showing that the 1 kpc scale-height results from a systematic bias in the analysis of pulsar data. This implies a higher thermal electron density in the Galactic halo, which in turn reduces the halo magnetic field strength to account for the observed rotation measures of extragalactic sources. We slightly modified the NE2001 model according to the new scale-height and revised the Sun et al. model parameters accordingly: the strength of the regular halo magnetic field is now 2 μG or lower, and the physically unrealistic cutoff in z for the cosmic-ray electron density is removed. The simulations based on the revised 3D-models reproduce all-sky observations as before.

title: A high-current hollow cathode as a source of intense line radiation in the VUV; abstract: The VUV line emission of a high-current DC hollow cathode was investigated in the wavelength region 10 nm to 100 nm. Spectra of quadruply ionised atoms could be observed. The radiance in the Al IV lines at 13 nm and 16 nm and in the He II Lyman-series was determined by a comparison with the spectral concentration of radiant intensity of the synchrotron radiation emitted by the electron storage ring BESSY. The authors found the radiance of the lines to be reproducible within +or-25%.

title: Low temperature magnetic hardness due to Co in CaCu5 type bulk materials; abstract: The coercive force at 4.2 K of bulk specimens YCo5−xNix and LaCo5−xNix increases from negligible values (of order Hc \u003c 1 kOe) for x = 0 to values of Hc of 11 and 27 kOe for the Y and La analog compounds with x = 3. This indicates that a transition metal alone can be responsible for the phenomenon of strong low temperature magnetic hardness in bulk specimens formerly found in various systems with anisotropic and magnetic rare earths. The coercive force of SmCo2Ni3 is larger than 50 kOe at 4.2 K while the analogous compound on the basis of Tb does not show coercive forces begond 0.5 kOe. The origins of the phenomenon are discussed briefly.

title: Neutrino masses and mixing parameters in a left-right model with mirror fermions; abstract: In this work we consider a left-right model containing mirror fermions with gauge group SU(3)$_{C} \\otimes SU(2)_{L} \\otimes SU(2)_{R} \\otimes U(1)_{Y^\\prime}$. The model has several free parameters which here we have calculated by using the recent values for the squared-neutrino mass differences. Lower bound for the mirror vacuum expectation value helped us to obtain crude estimations for some of these parameters. Also we estimate the order of magnitude of the masses of the standard and mirror neutrinos.

title: A 15 GSa/s, 1.5 GHz bandwidth waveform digitizing ASIC; abstract: The PSEC4 custom integrated circuit was designed for the recording of fast waveforms for use in largearea time-of-ight detector systems. The ASIC has been fabricated using the IBM-8RF 0.13 m CMOS process. On each of 6 analog channels, PSEC4 employs a switched capacitor array (SCA) 256 samples deep, a ramp-compare ADC with 10.5 bits of DC dynamic range, and a serial data readout with the capability of region-of-interest windowing to reduce dead time. The sampling rate can be adjusted between 4 and 15 Gigasamples/second [GSa/s] on all channels and is servo-controlled on-chip with a low-jitter delay-locked loop (DLL). The input signals are passively coupled on-chip with a -3 dB analog bandwidth of 1.5 GHz. The power consumption in quiescent sampling mode is less than 50 mW/chip; at a sustained trigger and readout rate of 50 kHz the chip draws 100 mW. After xed-pattern pedestal subtraction, the uncorrected dierential non-linearity is 0.15% over an 750 mV dynamic range. With a linearity correction, a full 1 V signal voltage range is available. The sampling timebase has a xed-pattern non-linearity with an RMS of

title: Rotational explosion mechanism for collapsing supernovae and the two-stage neutrino signal from supernova 1987A in the Large Magellanic Cloud; abstract: The two-stage (double) signal produced by the outburst of the close supernova (SN) in the Large Magellanic Cloud, which started on and involved two neutrino signals during the night of 23 February 1987 UT, is theoretically interpreted in terms of a scenario of rotationally exploding collapsing SNs, to whose class the outburst undoubtedly belongs. This scenario consists of a set of hydrodynamic and kinetic models in which key results are obtained by numerically solving non-one-dimensional and nonstationary problems. Of vital importance in this context is the inclusion of rotation effects, their role being particularly significant precisely in terms of the question of the transformation of the original collapse of the presupernova iron core to the explosion of the SN shell, with an energy release on a familiar scale of 1051 erg. The collapse in itself leads to the birth of neutron stars (black holes) emitting neutrino and gravitational radiation signals of gigantic intensity, whose total energy significantly (by a factor of hundreds) exceeds the above-cited SN burst energy. The proposed rotational scenario is described briefly by artificially dividing it into three (or four) characteristic stages. This division is dictated by the physical meaning of the chain of events a rotating iron core of a sufficiently massive (more than 10M) star triggers when it collapses. An attempt is made to quantitatively describe the properties of the associated neutrino and gravitational radiations. The review highlights the interpretation of the two-stage neutrino signal from SN 1987A, a problem which, given the present status of theoretical astrophysics, cannot, in the author\u0027s view, be solved without including rotation effects.

title: Large-eddy simulations of convective boundary layers using nonoscillatory differencing; abstract: Abstract We explore the ability of nonoscillatory advection schemes to represent the effects of the unresolved scales of motion in numerical simulation of turbulent flows. We demonstrate that a nonoscillatory fluid solver can accurately reproduce the dynamics of an atmospheric convective boundary layer. When an explicit turbulence model is implemented, the solver does not add any significant numerical diffusion. Of greater interest, when no explicit turbulence is employed the solver itself appears to include an effective subgrid scale model. Other researchers have reported similar success, simulating turbulent flows in a variety of regimes while using only nonoscillatory advection schemes to model subgrid effects. At this point there is no theory justifying this success, but we offer some speculations.

title: Light vector resonances in the effective chiral lagrangian for heavy mesons; abstract: We modify a chiral effective lagrangian, recently suggested to describe interactions of the light pseudoscalars with mesons containing a heavy quark, so as to incorporate light vector resonances, such as ϱ, etc. The modification uses the hidden gauge symmetry approach. As a preliminary example we present an application to the semileptonic D→K∗ decay.

title: Flow and heat transfer of power-law fluid over a rotating disk with generalized diffusion ☆; abstract: The study of swirling flows and heat transfer near various rotating machines, such as fans, turbines and centrifugal pumps, is necessary and important for many manufacturing processes in industry, especially the cooling of turbojet engines. The flow and heat transfer of power-law fluids over an infinite rotating disk is investigated in this paper. A generalized Fourier heat transfer model is introduced in which the thermal conductivity is assumed to depend on temperature gradient. New similarity variables are defined and the governing equations in the boundary layer are reduced to a set of coupling ordinary differential equations. An improved multi-shooting method is proposed to solve the resulting singular boundary value problems. The effects of the power-law index and local Prandtl number on velocity, pressure and temperature fields are analyzed. Especially, the viscosity coefficient and heat conductivity are discussed.

title: NUV Star Catalogue from the Lunar-based Ultraviolet Telescope Survey. First Release; abstract: We present a star catalogue extracted from the Lunar-based Ultraviolet Telescope (LUT) survey program. LUT\u0027s observable sky area is a circular belt around the Moon\u0027s north pole, and the survey program covers a preferred area for about 2400 deg$^2$ which includes a region of the Galactic plane. The data is processed with an automatic pipeline which copes with stray light contamination, artificial sources, cosmic rays, flat field calibration, photometry and so on. In the first release version, the catalogue provides high confidence sources which have been cross-identified with Tycho-2 catalogue. All the sources have signal-to-noise ratio larger than 5, and the corresponding magnitude limit is typically 14.4 mag, which can be deeper as ~16 mag if the stray light contamination is in the lowest level. A total number of 86,467 stars are recorded in the catalogue. The full catalogue in electronic form is available on line.

title: Monte Carlo simulation of electron transport in simple orthorhombically strained silicon; abstract: We report on the electron transport properties of simple orthorhombically strained silicon studied by density-functional theory and Monte Carlo simulation. The six degenerate valleys near X points in bulk silicon break into three pairs with different energy minima due to the orthorhombic strain. The degeneracy lifting causes electron redistribution among these valleys at low and intermediate electric fields. Thus the drift velocity is enhanced under an electric field transverse to the long axis of the lowest valleys. Orthorhombically strained layers should be of interest in vertical SiGe-based heterostructure n-channel–metal–oxide–semiconductor field effect transistors. The simple orthorhombically strained Si grown on a Si0.6Ge0.4 sidewall has a low-field mobility almost twice that of bulk Si and an electron saturation velocity approximately 20% higher.

title: Magnetic structures in DyNi1−xCuxAl pseudoternaries; abstract: Abstract The results of the neutron diffraction experiment preformed on the DyNi 1− x Cu x Al compounds are presented. Contrary to expectations based on bulk data, the DyCuAl exhibits just one magnetic component of the magnetic moments what makes it different from the other boundary compound DyNiAl. Quite a different behavior of the compound with x =0.2 from that one of x =0.1 now confirmed previous bulk data. The loss of the long-range magnetic order for compounds around x =0.8 was observed. This scenario is in accordance with previously studied pseudoternary systems with antiferromagentic to ferromagnetic order transition.

title: Contribution of the inelastic channels K − p → Yπ to the shift of the ground-state energy level of kaonic hydrogen; abstract: The contribution of the inelastic channels K{sup -}p {sup {yields}} Y{pi}, where Y{pi} = {sigma}{sup -}{pi}{sup +}, {sigma}{sup +}{pi}{sup -}, {sigma}{sup 0}{pi}{sup 0}, or {lambda}{sup 0}{pi}{sup 0}, kinematically allowed at the K{sup -}p threshold to the S-wave scattering length of elastic K{sup -}p scattering, as well as the shift of the ground-state energy of kaonic hydrogen, is calculated. The result, {delta}a{sub 0}{sup K-p} = -0.037 {+-} 0.010 fm and {delta}{epsilon}{sub 1s} = 15 {+-} 4 eV, will be important for the theoretical analysis of the expected data from the experiments scheduled by the DEAR and SIDDHARTA Collaborations at the end of 2006.

title: Tensor perturbations in a general class of Palatini theories; abstract: We study a general class of gravitational theories formulated in the Palatini approach and derive the equations governing the evolution of tensor perturbations. In the absence of torsion, the connection can be solved as the Christoffel symbols of an auxiliary metric which is non-trivially related to the space-time metric. We then consider background solutions corresponding to a perfect fluid and show that the tensor perturbations equations (including anisotropic stresses) for the auxiliary metric around such a background take an Einstein-like form. This facilitates the study in a homogeneous and isotropic cosmological scenario where we explicitly establish the relation between the auxiliary metric and the space-time metric tensor perturbations. As a general result, we show that both tensor perturbations coincide in the absence of anisotropic stresses.

title: Pulsar nulling and mode changing; abstract: With its relatively long observation time per pointing, the Parkes multibeam survey was effective in detecting nulling pulsars. We have made 2-h observations of 23 pulsars which showed evidence for pulse nulling or mode changing in the survey data. Because of the low flux density of these pulsars, in most cases averaging times of between 10 and 60 s were necessary and so this analysis is insensitive to very short nulls. Seven of the pulsars had null fractions of more than 40 per cent with the largest having a lower limit of 95 per cent. Mode changes were observed in six pulsars with clear relationships between nulling and mode changing in some cases. Combined with earlier results, the data suggest that large null fractions are more related to large characteristic age than to long pulse period. The observations suggest that nulling and mode changing are different manifestations of the same phenomenon.

title: Interactions between 4 He Nuclei and Protons at Intermediate Energies; abstract: Since the early 1970s, experiments have been performed to investigate the fragmentation of the lightest nuclei (d, 3H, 3He, and 4He) on protons at intermediate energies (∼0.2–2 GeV per nucleon). These experiments were set up in ITEP and LHE JINR and realized in an exclusive approach with the help of liquid hydrogen bubble chambers. This investigation is of great interest from two points of view: first, the possibility of detailed theoretical analysis of the data obtained in 4π geometry on the basis of a good understanding of the structure of the wavefunctions of these nuclei and, second, the search for exotic interaction mechanisms. This overview presents the latest, most interesting results of the ITEP experiment on the study of 4Hep interactions at 4He momenta of 2.7 and 5 GeV/c, on cross sections, elastic scattering, pair correlations of secondary nucleons, cumulative production of nucleons and the lightest nuclei (d, 3H, and 3He), the main features of exclusive reactions, and the search for possible multiquark bag production (dibaryons and tribaryons). The essential results of the independent JINR experiment at 8.6 and 13.6 GeV/c also come under discussion.

title: The ESO-Spitzer Imaging extragalactic Survey (ESIS). I. WFIB, V, R deep observations of ELAIS-S1 and comparison to Spitzer and GALEX data; abstract: Context. The ESO-Spitzer extragalactic Imaging Survey (ESIS) is the optical follow up of the Spitzer Wide-Area InfraRed Extragalactic (SWIRE) survey in the ELAIS-S1 area. Aims. The multiwavelength study of galaxy emission is the key to understand the interplay of the various components of galaxies and to trace their role in cosmic evolution. ESIS provides optical identification and colors of Spitzer IR galaxies and builds the bases for photometric redshift estimates. Methods. This paper presents  B , V , R  Wide Field Imager observations of the first 1.5 square degree of the ESIS survey. Data reduction is described including astrometric calibration, illumination and color corrections. Synthetic sources are simulated in scientific and super-sky-flat images, with the purpose of estimating completeness and photometric accuracy for the survey. Number counts and color distributions are compared to literature observational and theoretical data, including non-evolutionary, PLE, evolutionary and semi-analytic Λ CDM galaxy models, as well as Milky Way stellar predictions. The ELAIS-S1 area benefits from extensive follow-up from X-ray to radio frequencies: some potential uses of the multi-wavelength observations are illustrated. Results. Object coordinates are defined with an accuracy as good as ~0.15 [arcsec] rms with respect to GSC 2.2; flux uncertainties are ~2, 10, 20% at mag. 20, 23, 24 respectively (Vega); we reach 95% completeness at  B , $V\\sim 25$ and $R\\sim 24.5$. ESIS galaxy number counts are in good agreement with previous works and are best reproduced by evolutionary and hierarchical Λ CDM scenarios. Optical-Spitzer color-color plots promise to be very powerful tools to disentangle different classes of sources (e.g. AGNs, starbursts, quiescent galaxies). Ultraviolet GALEX data are matched to optical and Spitzer samples, leading to a discussion of galaxy properties in the UV-to-24  μ m color space. The spectral energy distribution of a few objects, from the X-rays to the far-IR are presented as examples of the multi-wavelength study of galaxy emission components in different spectral domains.

title: Signatures of Earth-scattering in the direct detection of Dark Matter; abstract: Direct detection experiments search for the interactions of Dark Matter (DM) particles with nuclei in terrestrial detectors. But if these interactions are sufficiently strong, DM particles may scatter in the Earth, affecting their distribution in the lab. We present a new analytic calculation of this \u0027Earth-scattering\u0027 effect in the regime where DM particles scatter at most once before reaching the detector. We perform the calculation self-consistently, taking into account not only those particles which are scattered away from the detector, but also those particles which are deflected towards the detector. Taking into account a realistic model of the Earth and allowing for a range of DM-nucleon interactions, we present the EarthShadow code, which we make publicly available, for calculating the DM velocity distribution after Earth-scattering. Focusing on low-mass DM, we find that Earth-scattering reduces the direct detection rate at certain detector locations while increasing the rate in others. The Earth\u0027s rotation induces a daily modulation in the rate, which we find to be highly sensitive to the detector latitude and to the form of the DM-nucleon interaction. These distinctive signatures would allow us to unambiguously detect DM and perhaps even identify its interactions in regions of the parameter space within the reach of current and future experiments.

title: Stellar Filaments in Self-Interacting Brans-Dicke Gravity; abstract: This paper is devoted to study cylindrically symmetric stellar filaments in self-interacting Brans-Dicke gravity. For this purpose, we construct polytropic filamentary models through generalized Lane-Emden equation in Newtonian regime. The resulting models depend upon the values of cosmological constant (due to scalar field) along with polytropic index and represent a generalization of the corresponding models in general relativity. We also investigate fragmentation of filaments by exploring the radial oscillations through stability analysis. This stability criteria depends only upon the adiabatic index.

title: Spectrum of weak magnetohydrodynamic turbulence.; abstract: Turbulence of magnetohydrodynamic waves in nature and in the laboratory is generally cross-helical or nonbalanced, in that the energies of Alfv\\\u0027en waves moving in opposite directions along the guide magnetic field are unequal. Based on high-resolution numerical simulations it is proposed that such turbulence spontaneously generates a condensate of the residual energy ${E}_{v}\\ensuremath{-}{E}_{b}$ at small field-parallel wave numbers. As a result, the energy spectra of Alfv\\\u0027en waves are generally not scale invariant in an inertial interval of limited extent. In the limit of an infinite Reynolds number, the universality is asymptotically restored at large wave numbers, and both spectra attain the scaling $E(k)\\ensuremath{\\propto}{k}_{\\ensuremath{\\perp}}^{\\ensuremath{-}2}$. The generation of a condensate is apparently related to the breakdown of mirror symmetry in nonbalanced turbulence.

title: Nuclear and neutron matter calculations with different model spaces; abstract: Abstract In this work we investigate the so-called model-space Brueckner-Hartree-Fock (MBHF) approach for nuclear matter as well as for neutron matter and the extension of this which includes the particle-particle and hole-hole (PPHH) diagrams. A central ingredient in the model-space approach for nuclear matter is the boundary momentum k M beyond which the single-particle potential energy is set equal to zero. This is also the boundary of the model space within which the PPHH diagrams are calculated. It has been rather uncertain which value should be used for k M . We have carried out model-space nuclear matter and neutron matter calculations with and without PPHH diagrams for various choices of k M and using several modern nucleon-nucleon potentials. Our results exhibit a saturation region where the nuclear and neutron matter energies are quite stable as k M varies. The location of this region may serve to determine an “optimum” choice for k M . However, we find that the strength of the tensor force has a significant influence on the variations of binding energy with k M . The implications for nuclear and neutron matter calculations are discussed.

title: Eccentric binary black hole inspiral-merger-ringdown gravitational waveform model from numerical relativity and post-Newtonian theory; abstract: We present a prescription for computing gravitational waveforms for the inspiral, merger and ringdown of non-spinning eccentric binary black hole systems. The inspiral waveform is computed using the post-Newtonian expansion and the merger waveform is computed by interpolating a small number of quasi-circular NR waveforms. The use of circular merger waveforms is possible because eccentric binaries circularize in the last few cycles before the merger, which we demonstrate up to mass ratio $q = m_1/m_2 = 3$. The complete model is calibrated to 23 numerical relativity (NR) simulations starting ~20 cycles before the merger with eccentricities $e_\\text{ref} \\le 0.08$ and mass ratios $q \\le 3$, where $e_\\text{ref}$ is the eccentricity ~7 cycles before the merger. The NR waveforms are long enough that they start above 30 Hz (10 Hz) for BBH systems with total mass $M \\ge 80 M_\\odot$ ($230 M_\\odot$). We find that, for the sensitivity of advanced LIGO at the time of its first observing run, the eccentric model has a faithfulness with NR of over 97% for systems with total mass $M \\ge 85 M_\\odot$ across the parameter space ($e_\\text{ref} \\le 0.08, q \\le 3$). For systems with total mass $M \\ge 70 M_\\odot$, the faithfulness is over 97% for $e_\\text{ref} \\lesssim 0.05$ and $q \\le 3$. The NR waveforms and the Mathematica code for the model are publicly available.

title: The theory of equilibrium critical phenomena; abstract: The theory of critical phenomena in systems at equilibrium is reviewed at an introductory level with special emphasis on the values of the critical point exponents α, β, γ,..., and their interrelations. The experimental observations are surveyed and the analogies between different physical systems - fluids, magnets, superfluids, binary alloys, etc. - are developed phenomenologically. An exact theoretical basis for the analogies follows from the equivalence between classical and quantal `lattice gases\u0027 and the Ising and Heisenberg-Ising magnetic models. General rigorous inequalities for critical exponents at and below Tc are derived. The nature and validity of the `classical\u0027 (phenomenological and mean field) theories are discussed, their predictions being contrasted with the exact results for plane Ising models, which are summarized concisely. Pade approximant and ratio techniques applied to appropriate series expansions lead to precise critical-point estimates for the three-dimensional Heisenberg and Ising models (tables of data are presented). With this background a critique is presented of recent theoretical ideas: namely, the `droplet\u0027 picture of the critical point and the `homogeneity\u0027 and `scaling\u0027 hypotheses. These lead to a `law of corresponding states\u0027 near a critical point and to relations between the various exponents which suggest that perhaps only two or three exponents might be algebraically independent for any system.

title: Magnetoresistance at artificial interfaces in epitaxial ferromagnetic thin films; abstract: Abstract Epitaxial La 2/3 Sr 1/3 MnO 3 and SrRuO 3 thin films have been grown by laser ablation on single-crystalline SrTiO 3 substrates. Prior to manganite or ruthenate deposition tracks have been patterned on the SrTiO 3 substrate by using an appropriately focused laser beam. In the experiments here reported linear tracks have been formed. The magnetotransport properties of the films, particularly the magnetoresistance, along paths parallel and perpendicular to the track have been extensively investigated and compared to similar data recorded on films grown on bicrystalline STO substrates. Whereas in LSMO a significant low-field tunnel magnetoresistance develops across the artificial interface, in SRO this tunnel contribution is absent. However, a significant high-field magnetoresistance is observed for both metallic and ferromagnetic systems. The results are analysed and discussed within the framework of the current understanding of double exchange and itinerant ferromagnets. Magnetoresistance data for various configurations of the track array are presented.

title: Dipping Activity in the X-Ray Pulsar 4U 1907+09; abstract: New observations of 4U 1907+09 with the Rossi X-Ray Timing Explorer show a kind of behavior never recognized before from this X-ray pulsar: intermittently, the X-ray intensity fades below the detection threshold during intervals ranging from a few minutes to perhaps 1.5 hours. The largest decrease of the 2-15 keV intensity is at least 98%. The observations span 70% of the orbit of the binary system of which the pulsar is a part. The dips were found to have a broad range of orbital phases. Given the strong variability of the source outside the dip periods with moderate changes in the spectrum, the occasional variable weak emission during dip periods with timescales and spectrum similar to that outside the dip periods, and the absence of strong enhancements in the column density of cold circumstellar matter (i.e., NH remains below 1023 cm-2), it is suggested that the dips are caused by cessations of the mass accretion by the neutron star rather than occultations by circumstellar gas. An inhomogeneous wind from the companion star may be responsible.

title: Quantitative Sum Rule Analysis of Low-Temperature Spectral Functions; abstract: We analyze QCD and Weinberg-type sum rules in a low-temperature pion gas using vector and axial-vector spectral functions following from the model-independent chiral-mixing scheme. Toward this end we employ recently constructed vacuum spectral functions with ground and first-excited states in both channels and a universal perturbative continuum; they quantitatively describe hadronic tau-decay data and satisfy vacuum sum rules. These features facilitate the implementation of chiral mixing without further assumptions, and lead to in-medium spectral functions which exhibit a mutual tendency of compensating resonance and dip structures, suggestive for an approach toward structureless distributions. In the sum rule analysis, we account for pion mass corrections, which turn out to be significant. While the Weinberg sum rules remain satisfied even at high temperatures, the numerical evaluation of the QCD sum rules for vector and axial-vector channels reveals significant deviations setting in for temperatures beyond ~140 MeV, suggestive of additional physics beyond low-energy chiral pion dynamics.

title: A 400-GHz Graphene FET Detector; abstract: This letter presents a graphene field effect transistor (GFET) detector at 400 GHz, with a maximum measured optical responsivity of 74 V/W, and a minimum noise-equivalent power of 130 pW/Hz1/2. This letter shows how the detector performance degrades as a function of the residual carrier concentration in the graphene channel, which is an important material parameter that depends on the quality of the graphene sheet and contaminants introduced during the fabrication process. In this work, the exposure of the graphene channel to liquid processes is minimized resulting in a low residual carrier concentration. This is in part, an important contributing factor to achieve the record high GFET detector performance. Thus, our results show the importance to use graphene with high quality and the importance to minimize contamination during the fabrication process.

title: Structural distortions induced during stress relaxation affecting electrical transport of nanometer-thick La0.67(Ba,Ca)0.33MnO3 films; abstract: X-ray diffraction (XRD) and medium-energy ion scattering (MEIS) were used to clarify distortions induced during mechanical stress relaxation in nanometer-thick epitaxial La0.67Ba0.33MnO3 (LBMO) and La0.67Ca0.33MnO3 (LCMO) films fabricated by pulsed laser deposition. It follows from measured XRD and MEIS spectra that LBMO films grown on mismatched LaAlO3 were partly relaxed in the main part of the film, leaving about 4 nm heavily strained portion close to the interface. The critical thickness of LCMO films grown on LaAlO3 substrates was several times larger than that of LBMO due to a better match in lattice parameters. Electro- and magneto-transport parameters of nanometer-thick manganite films grown on mismatched substrates differed markedly from those of LBMO and LCMO layers nucleated and grown on well-matched ones because of non-stoichiometry, biaxial mechanical stresses, and phase separation. The resistivity ρ of manganite films grown coherently at a substrate with small mismatch obeyed the relation ρ=ρ1+ρ2(H)T4.5 at temperatures well below the Curie point. Parameter ρ1 was temperature T and magnetic field H independent while ρ2 was temperature independent but decreased linearly with increasing H.

title: Polarons in crystalline and non-crystalline materials; abstract: The current state of polaron theory as applicable to transition metal oxides is reviewed, including problems such as impurity conduction where disorder plays a role. An estimate is given of the conditions under which polaron formation leads to an enhancement of the mass but no hopping energy. The binding energy of a polaron to a donor or acceptor in narrow-band semiconductors is discussed. The experimental evidence about the conductivity of TiO 2 and NiO is reviewed. Impurity conduction in NiO and conduction in glasses containing transition metal ions is discussed and it is emphasized that the activation energy for hopping nearly all vanishes at low temperatures. Pollak\u0027s theory of a.c. impurity conductivity is reviewed and applied to the problem of dielectric loss in these materials.

title: The GeV-TeV Galactic gamma-ray diffuse emission - I. Uncertainties in the predictions of the hadronic component; abstract: The Galactic gamma-ray diffuse emission is currently observed in the GeV-TeV energy range with unprecedented accuracy by the Fermi satellite. Understanding this component is crucial as it provides a background to many different signals such as extragalactic sources or annihilating dark matter. It is timely to reinvestigate how it is calculated and to assess the various uncertainties which are likely to affect the accuracy of the predictions. The Galactic gamma-ray diffuse emission is mostly produced above a few GeV by the interactions of cosmic ray primaries impinging on the interstellar material. The theoretical error on that component is derived by exploring various potential sources of uncertainty. Particular attention is paid to cosmic ray propagation. Nuclear cross sections, the proton and helium fluxes at the Earth, the Galactic radial profile of supernova remnants and the hydrogen distribution can also severely affect the signal. The propagation of cosmic ray species throughout the Galaxy is described in the framework of a semi-analytic two-zone diffusion/convection model. This allows to convert the constraints set by the boron-to-carbon data into a theoretical uncertainty on the diffuse emission. New deconvolutions of the HI and CO sky maps are also used to get the hydrogen distribution within the Galaxy. The thickness of the cosmic ray diffusive halo is found to have a significant effect on the Galactic gamma-ray diffuse emission while the interplay between diffusion and convection has little influence on the signal. The uncertainties related to nuclear cross sections and to the primary cosmic ray fluxes at the Earth are significant. The radial distribution of supernova remnants along the Galactic plane turns out to be a key ingredient. As expected, the predictions are extremely sensitive to the spatial distribution of hydrogen within the Milky Way.

title: A Correlation Between the Eclipse Depths of Kepler Gas Giant Candidates and the Metallicities of their Parent Stars; abstract: Previous studies of the interior structure of transiting exoplanets have shown that the heavy element content of gas giants increases with host star metallicity. Since metal-poor planets are less dense and have larger radii than metal-rich planets of the same mass, one might expect that metal-poor stars host a higher proportion of gas giants with large radii than metal-rich stars. Here I present evidence for a negative correlation at the 2.3-sigma level between eclipse depth and stellar metallicity in the Kepler gas giant candidates. Based on Kendall\u0027s tau statistics, the probability that eclipse depth depends on star metallicity is 0.981. The correlation is consistent with planets orbiting low-metallicity stars being, on average, larger in comparison with their host stars than planets orbiting metal-rich stars. Furthermore, since metal-rich stars have smaller radii than metal-poor stars of the same mass and age, a uniform population of planets should show a rise in median eclipse depth with [M/H]. The fact that I find the opposite trend indicates that substantial changes in gas giant interior structure must accompany increasing [M/H]. I investigate whether the known scarcity of giant planets orbiting low-mass stars could masquerade as an eclipse depth-metallicity correlation, given the degeneracy between metallicity and temperature for cool stars in the Kepler Input Catalog. While the eclise depth-metallicity correlation is not yet on firm statistical footing and will require spectroscopic [Fe/H] measurements for validation, it is an intriguing window into how the interior structure of planets and even the planet formation mechanism may be changing with Galactic chemical evolution.

title: Lattice Boltzmann simulation of nanofluid in lid-driven cavity; abstract: Lattice Boltzmann Method is applied to investigate the mixed convection flows utilizing nanofluids in a lid-driven cavity. The fluid in the cavity is a water-based nanofluid containing Cu, Cuo or Al2O3 nanoparticles. The effects of Reynolds number and solid volume fraction for different nanofluids on hydrodynamic and thermal characteristics are investigated. The effective thermal conductivity and viscosity of nanofluid are calculated by Chon and Brinkman models, respectively. The results indicate that the effects of solid volume fraction grow stronger sequentially for Al2O3, Cuo and Cu. In addition the increases of Reynolds number leads to decrease the solid concentration effect.

title: Nuclear Data Sheets for A = 124; abstract: The 1997 evaluation for A = 124 mass chain (1997Ii01) has been revised using experimental results from decays and reactions. Adopted values for the level and decay properties are tabulated. Inconsistencies and discrepancies are noted.

title: Oscillons from String Moduli; abstract: A generic feature of string compactifications is the presence of many scalar fields, called moduli. Moduli are usually displaced from their post-inflationary minimum during inflation. Their relaxation to the minimum could lead to the production of oscillons: localised, long-lived, non-linear excitations of the scalar fields. Here we discuss under which conditions oscillons can be produced in string cosmology and illustrate their production and potential phenomenology with two explicit examples: the case of an initially displaced volume modulus in the KKLT scenario and the case of a displaced blow-up Kaehler modulus in the Large Volume Scenario (LVS). One, in principle, observable consequence of oscillon dynamics is the production of gravitational waves which, contrary to those produced from preheating after high scale inflation, could have lower frequencies, closer to the currently observable range. We also show that, for the considered parameter ranges, oscillating fibre and volume moduli do not develop any significant non-perturbative dynamics. Furthermore, we find that the vacua in the LVS and the KKLT scenario are stable against local overshootings of the field into the decompatification region, which provides an additional check on the longevity of these metastable configurations.

title: Magnetodielectric coupling of a polar organic-inorganic hybrid Cr(II) phosphonate; abstract: Cr[(H(3)N-(CH(2))(2)-PO(3))(Cl)(H(2)O)] represents a rare example of a polar organic-inorganic hybrid material that exhibits a canted antiferromagnetic order below T(N)=5.5 K. The unusual coexistence of a polar crystal structure and magnetic order triggered our investigation of the magnetodielectric coupling. The coupling is evidenced by an anomaly in the temperature dependence of the dielectric constant epsilon below the Neel temperature. The magnetocapacitance is enhanced by one order of magnitude below T(N). The main characteristics of the magnetodielectic response are interpreted by Landau theoretical coupling terms.

title: Episodic mass ejections from common-envelope objects; abstract: After the initial fast spiral-in phase experienced by a common-envelope binary, the system mayenter a slow, self-regulated phase, possibly lasting hundreds of years, in which all the energy released by orbital decay can be efficiently transported to the surface, where it is radiated away.If the remaining envelope is to be removed during this phase, this removal must occur throughsome as-yet-undetermined mechanism. We carried out 1D hydrodynamic simulations of alow-mass red giant undergoing a synthetic common-envelope event in such a slow spiral-inphase, using the stellar evolutionary code MESA. We simulated the heating of the envelopedue to frictional dissipation from a binary companion\u0027s orbit in multiple configurations and investigated the response of the giant\u0027s envelope. We find that our model envelopes become dynamically unstable and develop large-amplitude pulsations, with periods in the range 3-20yr and very short growth time-scales of similar order. The shocks and associated rebounds that emerge as these pulsations grow are in some cases strong enough to dynamically eject shellsof matter of up to 0.1 M⊙, ~10 percent of the mass of the envelope, from the stellar surfaceat above escape velocity. These ejections are seen to repeat within a few decades, leading toa time-averaged mass-loss rate of the order of 10 -3 M⊙ yr -1 , which is sufficiently high torepresent a candidate mechanism for removing the entire envelope over the duration of theslow spiral-in phase.

title: Atomi orientati in campo magnetico variabile; abstract: L’autore calcola la probabilita che abbiano luogo processi non adiabatici quando un raggio di vapore orientato passa in prossimita di, un punto in cui il campo magnetico si anmulla.

title: Modeling and prediction of the effective thermal conductivity of random open-cell porous foams; abstract: Although highly desirable, accurate prediction of the effective thermal conductivity of high-porosity open-cell porous foam materials has remained to be a challenging problem. Aiming at this thorny obstacle, we have developed a random generation-growth method to reproduce the microstructures of open-cell foam materials via computer modeling, and then solve the energy transport equations through the complex structure by using a high-efficiency lattice Boltzmann method in this contribution. The effective thermal conductivities of open-cell foam materials are thus numerically calculated and the predictions are compared with the existing experimental data. Since the porosity is high, the predicted thermal conductivity caused by thermal conduction is lower than the measured data when the thermal conductivity of either component is very low and the radiation heat transfer is non-negligible. After considering the radiation effect, the numerical predictions agree rather well with the experimental data. The radiation influence is diminishing as the material porosity decreases. In general the effective thermal conductivity of open-cell foam materials is much higher than that of granular materials of the same components due to the enhanced heat transfer by the inner netlike morphology of the foam materials.

title: The heavily polluted atmosphere of the DAZ white dwarf GALEX J193156.8+011745; abstract: We report on the discovery of a new heavily polluted white dwarf. The DAZ white dwarf GALEX J193156.8+011745 was identified in a joint Galaxy Evolution Explorer (GALEX)/GSC survey of ultraviolet-excess objects. Optical spectra obtained at ESO New Technology Telescope show strong absorption lines of magnesium and silicon, and a detailed abundance analysis based on Very Large Telescope-Kueyen UVES spectra reveal super-solar abundances of silicon and magnesium and near-solar abundances of oxygen, calcium and iron. The overall abundance pattern bears the signature of on-going accretion on to the white dwarf atmosphere. The infrared spectral energy distribution shows an excess in the H and K bands likely associated with the accretion source.

title: Complexity Factor for Charged Spherical System; abstract: In this paper, we study the complexity factor for a charged anisotropic self-gravitating object. We formulate the Einstein-Maxwell field equations, Tolman-Opphenheimer-Volkoff equation, and the mass function. We form the structure scalars by the orthogonal splitting of the Riemann tensor and then find the complexity factor with the help of these scalars. Finally, we investigate some astrophysical objects for the vanishing of complexity condition. It is found that the presence of the electromagnetic field decreases the complexity of the system.

title: Phantom without ghost; abstract: The Nine-Year WMAP results combined with other cosmological data seem to indicate an enhanced favor for the phantom regime, comparing to previous analyses. This behavior, unless reversed by future observational data, suggests to consider the phantom regime more thoroughly. In this work we provide three modified gravitational scenarios in which we obtain the phantom realization without the appearance of ghosts degrees of freedom, which plague the naive approaches on the subject, namely the Brans-Dicke type gravity, the scalar-Einstein-Gauss-Bonnet gravity, and the $F(R)$ gravity, which are moreover free of perturbative instabilities. The phantom regime seems to favor the gravitational modification instead of the universe-content alteration.

title: Exploring the variable stars in the globular cluster NGC 5024 (M53): new RR Lyrae and SX Phoenicis stars; abstract: We report CCD V and I time series photometry of the globular cluster NGC 5024 (M53). The technique of difference image analysis has been used which enables photometric precisions better than 10 mmag for stars brighter than V ∼ 18.5 mag even in the crowded central regions of the cluster. The high photometric precision has resulted in the discovery of two new RR1 stars and 13 SX Phe stars. A detailed identification chart is given for all the variable stars in the field of our images of the cluster. Periodicities were calculated for all RR Lyrae and SX Phe stars and a critical comparison is made with previous determinations. Out of the four probable SX Phe variables reported by Dekany \u0026 Kovacs, the SX Phe nature is confirmed only for V80; V81 is an unlikely case while V82 and V83 remain as dubious cases. Previous misidentifications of three variables are corrected. Astrometric positions with an uncertainty of ∼0.3 arcsec are provided for all variables. The light-curve Fourier decomposition of RR0 and RR1 is discussed, we find a mean metallicity of [Fe/H] = ―1.92 ± 0.06 in the scale of Zinn \u0026 West from 19 RR0 stars. The true distance moduli 16.36 ± 0.05 and 16.28 ± 0.07 and the corresponding distances 18.7 ± 0.4 and 18.0 ± 0.5 kpc are found from the RR0 and RR1 stars, respectively. These values are in agreement with the theoretical period-luminosity relations for RR Lyrae stars in the I band and with recent luminosity determinations for the RR Lyrae stars in the Large Magellanic Cloud (LMC). The age of 13.25 ± 0.50 Gyr, for NGC 5024, E(B ― V) = 0.02 and the above physical parameters of the cluster, as indicated from the RR0 stars, produce a good isochrone fitting to the observed colour-magnitude diagram (CMD). The period-luminosity (PL) relation for SX Phe stars in NGC 5024 in the V and I bands is discussed in the light of the 13 newly found SX Phe stars, and their pulsation mode is identified in most cases.

title: Absolute E3 and M2 transition probabilities for the electromagnetic decay of the $\mathrm{\ensuremath I^{\pi}=K^{\pi}=8^{-}}$ isomeric state in 132Ce; abstract: The decay of the \\(\\ensuremath I^{\\pi}=K^{\\pi}=8^{-}\\) isomeric state at 2340keV in 132Ce has been investigated in the 120Sn(16O, 4n)132Ce reaction. The measurements were carried out in e -\\( \\gamma\\) and \\( \\gamma\\) -\\( \\gamma\\) coincidence modes using an electron spectrometer coupled to the OSIRIS II gamma-ray array at the Heavy Ion Laboratory of the University of Warsaw. Experimentally obtained internal conversion coefficients for the \\(\\ensuremath 8^{-} \\rightarrow 6^{+}\\) and \\(\\ensuremath 8^{-} \\rightarrow 5^{+}\\) transitions allowed the multipolarities, mixing ratios, reduced transition probabilities and hindrance factors to be determined.

title: Solar cycle evolution of the solar wind speed distribution from 1985 to 2008; abstract: [1] The evolution of solar wind speed distribution during the period 1985–2008, which covers two solar cycles (22 and 23), has been investigated using multistation interplanetary scintillation (IPS) measurements at 327 MHz. The results obtained here clearly demonstrate that fast (slow) wind areas increase (decrease) systematically as the solar activity diminishes, reaching the maximum (minimum) value at the minimum phase. The intermediate-speed wind areas appear to remain constant over the solar cycle. The preponderance of slow wind at low latitudes was confirmed from our IPS observations throughout the period, while a slight increase in the fast wind area was revealed in the declining to minimum phases. In contrast, the high-latitude solar wind was mostly dominated by the fast wind except for a few years around the maxima. An important point to note is the clear difference in the solar wind speed distribution between the 1996 and 2008 minima. The fast wind areas in 2008 showed a marked increase at low latitudes, which is consistent with in situ observations at 1 AU, and a distinct decrease at high latitudes, resulting in a net decrease at all latitudes, as compared with those in 1996. This difference is ascribed to the weaker polar fields during the 2008 minimum. An excellent positive (negative) correlation between fast (slow) wind areas and the polar fields is revealed from a comparison between IPS and magnetograph observations. The results obtained here suggest a strong control of the Sun\u0027s polar field in determining the solar wind acceleration and structure.

title: FORMALISM FOR INCLUSION OF MEASURED REACTION CROSS SECTIONS IN STELLAR RATES INCLUDING UNCERTAINTIES AND ITS APPLICATION TO NEUTRON CAPTURE IN THE s-PROCESS; abstract: A general formalism to include experimental reaction cross sections into calculations of stellar rates is presented. It also allows us to assess the maximally possible reduction of uncertainties in the stellar rates by experiments. As an example for the application of the procedure, stellar neutron capture reactivities from KADoNiS v0.3 are revised and the remaining uncertainties shown. Many of the uncertainties in the stellar rates are larger than those obtained experimentally. This has important consequences for s-process models and the interpretation of meteoritic data because it allows the rates of some reactions to vary within a larger range than previously assumed.

title: Thermodynamics of Asymptotically Locally AdS Spacetimes; abstract: We formulate the variational problem for AdS gravity with Dirichlet boundary conditions and demonstrate that the covariant counterterms are necessary to make the variational problem well-posed. The holographic charges associated with asymptotic symmetries are then rederived via Noether\u0027s theorem and `covariant phase space\u0027 techniques. This allows us to prove the first law of black hole mechanics for general asymptotically locally AdS black hole spacetimes. We illustrate our discussion by computing the conserved charges and verifying the first law for the four dimensional Kerr-Newman-AdS and the five dimensional Kerr-AdS black holes.