No abstract available

[en] Elastic scattering cross sections extracted for 412, 468, and 662 keV γ rays scattering by uranium, platinum, tungsten, barium, cadmium, and silver are reported at scattering angles from 30⁰ to 130⁰ using a Ge-Li detector. The results are compared with theoretical cross sections obtained from the Dirac-Hartree-Fock-Slater form-factor approximation and correction factors evaluated by interpolation techniques from recent second order perturbation scattering amplitude calculations. Good agreement between the measurements and theory exists when both the K and L shell contributions to Rayleigh scattering are included

[en] In this paper we introduce a notion of free energy and large deviations rate function for asymptotically additive sequences of potentials via an approximation method by families of continuous potentials. We provide estimates for the topological pressure of the set of points whose non-additive sequences are far from the limit described through Kingman’s sub-additive ergodic theorem and give some applications in the context of Lyapunov exponents for diffeomorphisms and cocycles, and the Shannon-McMillan-Breiman theorem for Gibbs measures. (paper)

[en] We study Poincaré recurrence from a purely geometrical viewpoint. In (Downarowicz and Weiss 2004 Illinois J. Math. 48 59–69) it was proven that the metric entropy is given by the exponential growth rate of return times to dynamical balls. Here we use combinatorial arguments to provide an alternative and more direct proof of this result and to prove that minimal return times to dynamical balls grow linearly with respect to its length. Some relations using weighted versions of recurrence times are also obtained for equilibrium states. Then we establish some interesting relations between recurrence, dimension, entropy and Lyapunov exponents of ergodic measures

[en] We use a sample of 149 spectroscopically confirmed UV-selected galaxies at z ∼ 2 to investigate the relative dust attenuation of the stellar continuum and the nebular emission lines. For each galaxy in the sample, at least one rest-frame optical emission line (Hα/[N ii] λ6583 or [O iii] λ5007) measurement has been taken from the litterature, and 41 galaxies have additional Spitzer/MIPS 24 μm observations that are used to infer infrared luminosities. We use a spectral energy distribution (SED) fitting code that predicts nebular line strengths when fitting the stellar populations of galaxies in our sample, and we perform comparisons between the predictions of our models and the observed/derived physical quantities. We find that on average our code is able to reproduce all the physical quantities (e.g., UV β slopes, infrared luminosities, emission line fluxes), but we need to apply a higher dust correction to the nebular emission compared to the stellar emission for the largest star formation rate (SFR) (log SFR/M_⊙ yr"−"1 > 1.82, Salpeter initial mass function). We find a correlation between SFR and the difference in nebular and stellar color excesses, which could resolve the discrepant results regarding nebular dust correction at z ∼ 2 from previous studies

No abstract available

[en] Let N be the space of Gaussian distribution functions over ℝ, regarded as a 2-dimensional statistical manifold parameterized by the mean μ and the deviation σ. In this paper, we show that the tangent bundle of N, endowed with its natural Kähler structure, is the Siegel-Jacobi space appearing in the context of Number Theory and Jacobi forms. Geometrical aspects of the Siegel-Jacobi space are discussed in detail (completeness, curvature, group of holomorphic isometries, space of Kähler functions, and relationship to the Jacobi group), and are related to the quantum formalism in its geometrical form, i.e., based on the Kähler structure of the complex projective space. This paper is a continuation of our previous work [M. Molitor, “Remarks on the statistical origin of the geometrical formulation of quantum mechanics,” Int. J. Geom. Methods Mod. Phys. 9(3), 1220001, 9 (2012); M. Molitor, “Information geometry and the hydrodynamical formulation of quantum mechanics,” e-print arXiv (2012); M. Molitor, “Exponential families, Kähler geometry and quantum mechanics,” J. Geom. Phys. 70, 54–80 (2013)], where we studied the quantum formalism from a geometric and information-theoretical point of view

[en] In this paper we study the distributions of hitting and return times for observations of dynamical systems. We apply the results to get an exponential law for the distributions of hitting and return times for rapidly mixing random dynamical systems. In particular, this allows us to obtain an exponential law for random expanding maps, random circle maps expanding on average and randomly perturbed dynamical systems. (paper)

[en] Differential cross sections for Compton scattering on Cu, Zn, Cd, Sn, W, Pt, Pb, and U were measured for scattering angles between 5⁰ to 60⁰. The measurements are in agreement with values of the incoherent-scattering-factor theory, and for small scattering angles deviations from the free-electron Klein-Nishina value occur

No abstract available