Computing Neutron Capture Rates in Neutron-Degenerate Matter

Universe

Bryn Knight¹  Liliana Caballero¹ 

[1] Department of Physics, University of Guelph, Guelph, ON N1G 2W1, Canada;

关键词: neutron capture;    neutron stars;    degenerate matter;    nuclear reactions;   

DOI  :  10.3390/universe5010036

来源: DOAJ

【 摘 要 】

Neutron captures are likely to occur in the crust of accreting neutron stars (NSs). Their rate depends on the thermodynamic state of neutrons in the crust. At high densities, neutrons are degenerate. We find degeneracy corrections to neutron capture rates off nuclei, using cross sections evaluated with the reaction code TALYS. We numerically integrate the relevant cross sections over the statistical distribution functions of neutrons at thermodynamic conditions present in the NS crust. We compare our results to analytical calculations of these corrections based on a power-law behavior of the cross section. We find that although an analytical integration can simplify the calculation and incorporation of the results for nucleosynthesis networks, there are uncertainties caused by departures of the cross section from the power-law approach at energies close to the neutron chemical potential. These deviations produce non-negligible corrections that can be important in the NS crust.

【 授权许可】

Unknown