Nuclear reactions in hot astrophysical plasmas with $T>10^{10}$ K

TL;DR

This paper investigates nuclear reactions in extremely hot astrophysical plasmas exceeding 10^{10} K, using the TALYS code to analyze nuclear composition and gamma-ray emissions relevant to black holes and neutron stars.

Contribution

It provides a comprehensive nuclear reaction network for hot plasmas and studies their chemical evolution and gamma-ray signatures, filling data gaps for high-temperature astrophysics.

Findings

Calculated abundances of light elements like D, T, He-3, He-4, Li, Be, and B.

Analyzed prompt gamma-ray emissions from hot plasmas.

Discussed implications for astrophysical element abundances.

Abstract

The importance of nuclear reactions in low-density astrophysical plasmas with ion temperatures $T \geq 10^{10}$ K has been recognized for more than thirty years. However, the lack of comprehensive data banks of relevant nuclear reactions and the limited computational power have not previously allowed detailed theoretical studies. Recent developments in these areas make it timely to conduct comprehensive studies on the nuclear properties of very hot plasmas formed around compact relativistic objects such as black holes and neutron stars. Such studies are of great interest in the context of scientific programs of future low-energy cosmic $\gamma$-ray spectrometry. In this work, using the publicly available code TALYS, we have built a large nuclear network relevant for temperatures exceeding $10^{10}$ K. We have studied the evolution of the chemical composition and accompanying prompt gamma-ray emission of such high temperature plasmas. We present the results on the abundances of light elements D, T, $^3$He, $^4$He, $^{6}$Li, $^{7}$Li $^{9}$Be, $^{10}$B, $^{11}$B, and briefly discuss their implications on the astrophysical abundances of these elements.