Abstract: Using a nonrelativistic constituent quark model in which the degrees of freedom are quarkantiquark and meson- meson components, we have recently shown that the Dd((*))K thresholds play an important role in lowering the mass of the c (S) over bar states associated with the physical D-s0(*)(2317) and D-s1(2460) mesons. This observation is also supported by other theoretical approaches such as latticeregularized QCD or chiral unitary theory in coupled channels. Herein, we extend our computation to the lowest P- wave Bs mesons, taking into account the corresponding J(P) = 0(+), 1(-) and 2(+) bottomstrange states predicted by the naive quark model and the BK and B* K thresholds. We assume that mixing with B-s((*))eta and isospin-violating decays to B-s((*))pi are negligible. This computation is important because there is no experimental data in the b (S) over bar sector for the equivalent j(q)(p) = 1/2(+) (D-s0(*)(2317), D-s1 (2460)) heavy-quark multiplet and, as it has been seen in the c (s) over bar sector, the naive theoretical result can be wrong by more than 100 MeV. Our calculation allows us to introduce the coupling with the D-wave B*K channel and to compute the probabilities associated with the different Fock components of the physical state.

Abstract: The low-lying energy levels of proton-rich Cu-56 have been extracted using in-beam gamma-ray spectroscopy with the state-of-the-art gamma-ray tracking array GRETINA in conjunction with the S800 spectrograph at the National Superconducting Cyclotron Laboratory at Michigan State University. Excited states in Cu-56 serve as resonances in the Ni-55(p,gamma)Cu-56 reaction, which is a part of the rp process in type-I x-ray bursts. To resolve existing ambiguities in the reaction Q value, a more localized isobaric multiplet mass equation (IMME) fit is used, resulting in Q = 639 +/- 82 keV. We derive the first experimentally constrained thermonuclear reaction rate for Ni-55(p,.) Cu-56. We find that, with this newrate, the rp processmay bypass the (56)Niwaiting point via the Ni-55(p,gamma) reaction for typical x-ray burst conditions with a branching of up to similar to 40%. We also identify additional nuclear physics uncertainties that need to be addressed before drawing final conclusions about the rp-process reaction flow in the Ni-56 region.

Abstract: In a well-established many-body framework, successful in modeling a great variety of nuclear processes, we analyze the role of the spectral functions (SFs) accounting for the modifications of the dispersion relation of nucleons embedded in a nuclear medium. We concentrate in processes mostly governed by one-body mechanisms, and study possible approximations to evaluate the particle hole propagator using SFs. We also investigate how to include together SFs and long-range RPA-correlation corrections in the evaluation of nuclear response functions, discussing the existing interplay between both type of nuclear effects. At low energy transfers (<= 50 MeV), we compare our predictions for inclusive muon and radiative pion captures in nuclei, and charge-current (CC) neutrino-nucleus cross sections with experimental results. We also present an analysis of intermediate energy quasi-elastic neutrino scattering for various targets and both neutrino and antineutrino CC driven processes. In all cases, we pay special attention to estimate the uncertainties affecting the theoretical predictions. In particular, we show that errors on the a,,sigma(mu)/sigma(e) ratio are much smaller than 5%, and also much smaller than the size of the SF+RPA nuclear corrections, which produce significant effects, not only in the individual cross sections, but also in their ratio for neutrino energies below 400 MeV. These latter nuclear corrections, beyond Pauli blocking, turn out to be thus essential to achieve a correct theoretical understanding of this ratio of cross sections of interest for appearance neutrino oscillation experiments. We also briefly compare our SF and RPA results to predictions obtained within other representative approaches.