Nucleosynthesis from neutrino-dominated accretion disks in gamma-ray bursts and its application

¹ Department of Astronomy and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen, Fujian 361005, China
² State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190, China

^a e-mail: tongliu@xmu.edu.cn

Published online: 20 March 2014

Abstract

We investigate the element distribution in neutrino-dominated accretion flows around black holes with the proton-rich nuclear statistical equilibrium. According to our calculations, the radial nuclei distribution (around equatorial plane) is dominated by free nucleons, ⁴He, and ⁵⁶Fe in the inner, middle, and outer region, respectively. For the vertical distribution, the heavy nuclei tend to be produced in a thin region near the disk surface, in which we find that ⁵⁶Ni is dominant for the flow with low accretion rate but it would switch to ⁵⁶Fe for high accretion rate. Our results imply that ⁵⁶Ni produced by central engine would tend to outflow and subsequently decay to drive the bumps observed in the light curves of the core collapse supernovae.