Electron capture rates on titanium isotopes in stellar matter

TL;DR

This paper calculates electron capture rates on titanium isotopes in stellar environments using pn-QRPA theory, highlighting their importance in supernova core collapse and comparing results with previous models.

Contribution

It provides new electron capture rate calculations for titanium isotopes across wide stellar conditions using pn-QRPA, and compares these with earlier shell model results.

Findings

Electron capture rates vary significantly with density and temperature.

The pn-QRPA results differ from previous shell model calculations.

These rates impact models of stellar core collapse and supernovae.

Abstract

Electron captures are amongst the most important weak interaction rates related to the dynamics of stellar core collapse. They play a key role in the gravitational collapse of the core of a massive star triggering the supernova explosion. Titanium isotopes are believed to have significant impact on controlling the lepton-to-baryon fraction in the late phases of evolution of core of massive stars. This work consists of the calculation of electron capture rates on titanium isotopes. The pn-QRPA theory is used to calculate electron capture rates in stellar matter. The electron capture rates are calculated over a wide range of densities (10 \leq {\rho}Ye (g cm-3) \leq 1011) and temperatures (107 \leq T (K) \leq 30 \times 109). Here we also report the differences in electron capture rates with the earlier calculations including those using large scale shell model.