Status of nuclear physics behind nucleosynthesis processes: The role of exotic neutron-rich nuclei

Abstract

We give a brief overview of the current status of important nuclear physics inputs, like reaction rates, in hydrostatic and explosive nucleosynthesis. Recently, it has been proposed that exotic neutron-rich nuclei play an important role even in the formation of heavy elements via the r-process. The main problems here are identification, abundance estimation of seed nuclei in these processes, and their pathways. We will try to highlight how improved nuclear structure and reaction calculations can affect our present understanding of radiative capture rates of light-mass and medium-mass nuclei, which in turn can drastically influence the abundance of heavier-mass elements.

Estimation of radiative capture 13B(n, γ 0+1)14B reaction rate in the modified potential cluster model*

“…where N1 = E1 or M1, μ is the reduced mass in the n + 13 B channel, K is the γ-quantum wave number, , k is the relative motion wave number related to the non-relativistic kinetic energy as , J i and J f are the total angular momenta, the multipolarity is fixed as the dipole J = 1, and are the radial matrix elements over the relative distance r. We use masses of m n = 1.00866491597 amu [24] and = 13.0177802 amu [25], and the constant = 41.4686 MeV•fm 2 , where m 0 is the atomic mass unit (amu). The magnetic moments in (5) are given in nuclear magneton μ N : μ n = −1.9130μ N , and = 3.1778 μ N [18,19,24,25].…”

“…Short-lived isotopes may provide r-processes in an explosive environment and neutron-rich matter at high densities [37]. The conventional density -temperature conditions for the r-process are assumed as ~ 10 22 -10 23 cm −3 and T 9 ~ 1 [2,38]. We examine these conditions for the 13 B(n, γ) 14 B reaction based on the calculated reaction rates.…”

“…Conventional studies on r-processes focus on producing heavy unstable nuclei. Among the thousands of publications, one may be impressed by the recent reviews [1][2][3].…”