The doubly exci ted 2s2p 1 P 1 level of Kr + populated via resonant transfer and excitation (RTE) feeds selectively the metastable ls2s 1S0 state which can only decay via sirnultaneous emission of two photons to the ground state ls2 1So. X-rayIX-ray coincidenee measurements in heavy ionatom collisions enable the direct measurement of the spectral distribution of the two-photon decay in He-like ...

In 1967 Glashow, Schnitzer and Weinberg derived a sum rule in the soft pion and soft kaon limit relating the ∆I = 1 2 non-leptonic K → 2π amplitude to integrals over strange and non-strange spectral functions. Using the recent ALEPH data from τ -decay, we show that the sum rule, slightly modified to reduce contributions near the cut, yields the correct magnitude decay amplitude corresponding to...

Swift captured for the first time a smoothly rising X-ray re-brightening of clear nonflaring origin after the steep decay in a long gamma-ray burst (GRB): GRB081028. A rising phase is likely present in all GRBs but is usually hidden by the prompt tail emission and constitutes the first manifestation of what is later to give rise to the shallow decay phase. Contemporaneous optical observations r...

Nelson R. F. Braga∗ and Luiz F. Ferreira† Instituto de F́ısica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, RJ 21941-972 – Brazil Abstract We present a holographic description of the thermal behavior of bb̄ heavy vector mesons inside a plasma at finite temperature and density. The meson dissociation in the medium is represented by the decrease in the height of the spectral functio...

The abBA collaboration proposes to conduct a comprehensive program of precise measurements of neutron β-decay coefficients a (the correlation between the neutrino momentum and the decay electron momentum), b (the electron energy spectral distortion term), A (the correlation between the neutron spin and the decay electron momentum), and B (the correlation between the neutron spin and the decay n...

In that paper, we prove an equivalence between Nash-type inequalities and an exponential decay (in the sense of the definition 2.2) for symmetric submarkovian semigroups. This exponential decay generalizes the notion of spectral gap where this number is replaced by a function. We discuss different formulations of the decay associated to the usual Nash inequality in terms of Lyapunov-type functi...

We propose to study echo dynamics in a random matrix framework, where we assume that the perturbation is time independent, random and orthogonally invariant. This allows to use a basis in which the unperturbed Hamiltonian is diagonal and its properties are thus largely determined by its spectral statistics. We concentrate on the effect of spectral correlations usually associated to chaos and di...

Remotely sensed data represents key information for characterizing and estimating biodiversity. Spectral distance among sites has proven to be a powerful approach for detecting species composition variability. Regression analysis of species similarity versus spectral distance may allow us to quantitatively estimate how beta-diversity in species changes with respect to spectral and ecological va...

In this paper, we propose a new generalized Hermite spectral method. We introduce an orthogonal family of new generalized Hermite functions, with the weight function (1 + 2 π arctanx) α(1 − 2 π arctanx)γ , α and γ being arbitrary real numbers. The basic results on the corresponding orthogonal approximation and interpolation are established. As examples of applications, we provide the spectral s...

We study cascades with partial which path ambiguity where entan-glement is distilled by spectral filtering. We develop a framework to calculate the amplitudes and phases of the density matrix. The results can be summarized in a two dimensional " phase diagram ". The theory is applied to the quantum tomography of the decay cascade of a biex-citon in a semiconductor quantum dot. The effect of inh...