Related papers: Thermal Contributions to Primordial Nucleosynthesi…
In this contribution we will review our present understanding of the matter equation of state in the density and temperature conditions where it can be described by nucleonic degrees of freedom. At zero temperature, all the information is…
We present nucleosynthesis studies based on hydrodynamical simulations of core-collapse supernovae and their subsequent neutrino-driven winds. Although the conditions found in these simulations are not suitable for the rapid neutron capture…
We calculate numerically the quasiparticle effective mass (m*) renormalization as a function of temperature and electron density in two- and three-dimensional electron systems with long-range Coulomb interaction. In two dimensions, the…
The influence of the electron environment on the alpha decay is elucidated. Within the frame of a simple model based on the generalized Thomas-Fermi theory of the atom, it is shown that the increase of the electron density around the parent…
The electron capture process plays an important role in the evolution of the core collapse of a massive star that precedes the supernova explosion. In this study, the electron capture on nuclei in stellar environment is described in the…
We consider the implications of the modified dispersion relations, due to the noncommutativity of the spacetime, for a photon gas filling the early Universe in the framework of the Big Bang Nucleosynthesis (BBN) processes, during the period…
We study effects of long-lived massive particles, which decay during the big-bang nucleosynthesis (BBN) epoch, on the primordial abundances of light elements. Compared to the previous studies, (i) the reaction rates of the standard BBN…
We recalculate the two loop corrections in the background heat bath using real time formalism. The procedure of the integrations of loop momenta with dependence on finite temperature before the momenta without it, has been followed. We…
In the primordial Universe, neutrino decoupling occurs only slightly before electron-positron annihilations, leading to an increased neutrino energy density with order $10^{-2}$ spectral distortions compared to the standard instantaneous…
Reheating is a process where the energy density of a dominant component of the universe other than radiation, such as a matter component, is transferred into radiation. It is usually assumed that the temperature of the universe decreases…
Finite temperature field theory is used to calculate the correction to the mass of the electron in plasma with finite temperature and arbitrary chemical potential, and the results are applied to the core regions of type II supernovae (SNe).…
We consider energy deposition of high energy electrons and photons in universe. We carry out detailed calculations of fractions of the initial energy of the injected electron or photon which are used to heat, ionize and excite background…
We point out that the existence of metastable, tau > 10^3 s, negatively charged electroweak-scale particles (X^-) alters the predictions for lithium and other primordial elemental abundances for A>4 via the formation of bound states with…
The effects of introducing a small amount of non-thermal distribution (NTD) of elements in big bang nucleosynthesis (BBN) are studied by allowing a fraction of the NTD to be time-dependent so that it contributes only during a certain period…
The theoretical predictions of the primordial abundances of elements in the big-bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction rates. We investigate the effect of modifying these reaction rates on…
Nuclear masses play a fundamental role in understanding how the heaviest elements in the Universe are created in the $r$-process. We predict $r$-process nucleosynthesis yields using neutron capture and photodissociation rates that are based…
The temperature dependence of stellar electron-capture (EC) rates is investigated, with a focus on nuclei around $N=50$, just above $Z=28$, which play an important role during the collapse phase of core-collapse supernovae (CCSN). Two new…
We re-investigate the evolution of the strongly degenerate neutrinos in the early universe. With the larger degeneracy, the neutrino number freezes at higher temperatures because the neutrino annihilation rate decreases. We consider very…
Experimental measurements in terrestrial laboratory, space and astrophysical observations of variation and fluctuation of nuclear decay constants, measurements of large enhancements in fusion reaction rate of deuterons implanted in metals…
We investigate the influences of the nuclear composition on the weak interaction rates of heavy nuclei during the core collapse of massive stars. The nuclear abundances in nuclear statistical equilibrium (NSE) are calculated by some…