Explosive nucleosynthesis of ultra-stripped Type Ic supernovae: application to light trans-iron elements

TL;DR

This study models the explosive nucleosynthesis in ultra-stripped Type Ic supernovae, highlighting their role in producing light trans-iron elements and neutron-rich isotopes, with implications for understanding supernova contributions to galactic chemical evolution.

Contribution

It provides the first detailed two-dimensional explosion models of ultra-stripped Type Ic supernovae, quantifying their nucleosynthesis yields and light curve characteristics.

Findings

Ultra-stripped supernovae produce light trans-iron elements Ga-Zr.

They eject about 0.006-0.01 M$_\odot$ of $^{56}$Ni.

These supernovae have sub-luminous, fast-decaying light curves.

Abstract

We investigate the explosive nucleosynthesis during two dimensional neutrino-driven explosion of ultra-stripped Type Ic supernovae evolved from 1.45 and 1.5 M$_\odot$ CO stars. These supernovae explode with the explosion energy of $\sim 10^{50}$ erg and release $\sim 0.1$ M$_\odot$ ejecta. The light trans-iron elements Ga-Zr are produced in the neutrino-irradiated ejecta. The abundance distribution of these elements has a large uncertainty because of the uncertainty of the electron fraction of the neutrino-irradiated ejecta. The yield of the elements will be less than 0.01 M$_\odot$. Ultra-stripped supernova and core-collapse supernova evolved from a light CO core can be main sources of the light trans-iron elements. They could also produce neutron-rich nuclei $^{48}$Ca. The ultra-stripped supernovae eject $^{56}$Ni of $\sim$ 0.006 - 0.01 M$_\odot$. If most of neutrino-irradiated ejecta is proton-rich, $^{56}$Ni will be produced more abundantly. The light curves of these supernovae indicate sub-luminous fast decaying explosion with the peak magnitude of about $-15$ - $-16$. Future observations of ultra-stripped supernovae could give a constraint to the event rate of a class of neutron star mergers.