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Production of elements heavier than iron, their abundance and cite of production remain an active field of research to-date. In this paper I would present a brief review of the nucleosynthesis process and then focus further on the proton capture processes with particular emphasis on the nuclear physics aspects of the rp-process. The present calculation clearly shows that the electron capture rates on waiting point nuclei are at least of similar magnitude as the competing positron decay rates under rp-process conditions. The study strongly suggests that electron capture rates form an integral part of weak-interaction mediated rates under rp-process conditions and should not be neglected in nuclear reaction network calculations as done in past.

Neutrino energy loss rates are required as a key nuclear physics input parameter in the simulation codes of core‐collapse supernovae of massive stars. The weak interaction rates due to isotopes of iron, 54,55,56Fe, are considered to play an important role during the presupernova evolution of massive stars. Proton‐neutron quasi‐particle random phase approximation (pn‐QRPA) theory has recently being used for a microscopic calculation of stellar weak interaction rates of iron isotopes with success. The calculation of neutrino energy loss rates due to 54,55,56Fe is presented along with a comparison with large scale shell model results.

During the late phases of stellar evolution beta decay on iron isotopes, in the core of massive stars, plays a crucial role in the dynamics of core‐collapse. The beta decay contributes in maintaining a ‘respectable’ lepton‐to‐baryon ratio (Ψe) of the core prior to collapse which results in a larger shock energy to power the explosion. It is indeed a fine tuning of the parameter Ψe at various stages of supernova physics which can lead to a successful transformation of the collapse into an explosion. The calculations presented here might help in fine‐tuning of Ψe for the collapse simulators of massive stars.

Nuclear level densities are important in nuclear physics for a number of reasons. They are required in the designing of fission and fusion reactors, they have medical as well as astrophysical applications. Of the many important consequences of level densities in astrophysics, I am mainly concerned here with the nucleosynthesis problem. Nucleosynthesis calculations require nuclear level densities for hundreds or even thousands of nuclides. Ideally one would like to constrain these level densities by microscopically motivated yet computationally cheap models. A statistical approach suggests that low moments of the Hamiltonian might be sufficient. Recently Zuker proposed a simple combinatoric formula for level densities based upon the binomial distribution. In this paper I rigorously test the binomial formula against full scale shell‐model diagonalization calculations for selected sd‐ and fp‐shell nuclides and also against Monte Carlo path integration calculations.