A Comparative Study on SN II Progenitors for the Synthesis of Li-7 and B-11 with the help of Neutrinos

作者：Lahkar N^*; Kalita S; Duorah H L; Duorah K

来源：Journal of Astrophysics and Astronomy, 2015, 36(3): 375-383.

DOI：10.1007/s12036-015-9339-8

• Supernova progenitor
• neutrino process
• neutral current

The synthesis of Li-7 and B-11 confronts astrophysicists. Type II (SN II) and Type Ic (SN Ic) supernovae are supposed to be the producers of these two elements. In this study we calculate the yields of these two elements for SN II progenitors with 8, 10 and 20 solar masses. The process considered here is the neutral current interaction of heavy flavour neutrinos (nu (mu) or nu (tau) ) with He-4 nuclei of the helium zone. The low mass progenitors are considered because the helium zone lies much closer to the core and hence experiences large neutrino flux. The starting point of the helium zone depends on detail stellar model. However, the shell radius at which it begins is available for these stars. 20 solar mass is considered for comparison of our production ratio Li/B with that of an earlier work. It is contrasted with the shock heating yields in the hydrogen envelope. The Li/B ratio has been found to be about 0.96. In the three model stars, the Li-7 and B-11 yields are found to be in the range 6.61x10(-6)-2.63x10(-6) M (Sun) and 6.92x10(-6)-2.75x10(-6) M (Sun) respectively as we go from 8 to 20M (Sun). Some equivalence is found with shock induced nucleosynthesis model for SN II. The SN II yield is found to be compatible with that of hypernovae produced by C-O core collapse but higher than the yields obtained by neutrino processes in SNIc.

• 出版日期2015-9