The chemical yields of stars in the range 9-15 Msun

TL;DR

This study computes detailed chemical yields of stars with masses 9-15 Msun, revealing how yields vary with initial mass and their limited contribution to overall galactic chemical enrichment, with implications for supernova observations.

Contribution

It extends previous models by providing detailed nucleosynthesis yields for 9-15 Msun stars using a thermal bomb explosion framework.

Findings

Yields of intermediate elements decrease with initial mass.

Yields of s-weak component decrease linearly with initial mass.

Stars in this mass range have negligible contribution to overall isotope yields.

Abstract

In Limongi et al. (2024) we presented and discussed the main evolutionary properties and final fate of stars in the mass range 7-15 Msun. The evolutions of those models were computed by means of a medium size nuclear network that guaranteed a proper calculation of the nuclear energy generation and hence a good modeling of the physical evolution of these stars. In the present paper, we extend this study by computing the detailed chemical yields of stars in the mass range 9-15 Msun, i.e., those stars that explode as core collapse supernovae (CCSNe). The explosive nucleosynthesis is then computed in the framework of the thermal bomb induced explosion by means of the HYPERION code (Limongi and Chieffi 2020). We find that: (1) the yields of the intermediate mass elements (i.e., O to P) show a steep decrease as the inital mass decreases; (2) the yields of s-weak component, i.e., those produced by the slow neutron captures from Ga to to the first neutron closure shell, decrease almost linearly as a function of the initial mass with respect to the ones produced by the more massive stars; (3) the global contribution of the stars in the mass range 9.22-13 Msun to the yields of a generation of massive stars averaged over a standard initial mass function is negligible for essentially all the isotopes. In spite of this, however, the models of stars in this mass range can be fundamental to interpret the observations of specific supernovae.