# Type IIb supernova progenitors by fatal common envelope evolution

## TL;DR

This study uses stellar evolution simulations to demonstrate that the fatal common envelope evolution channel can produce Type IIb supernova progenitors with minimal hydrogen, aligning with observational data.

## Contribution

It introduces a new evolutionary pathway involving a tidally destroyed secondary star forming a giant envelope, explaining SNe IIb progenitors with low hydrogen mass.

## Key findings

- The fatal CEE channel can produce SNe IIb progenitors with 0.02-0.09 solar masses of hydrogen.
- Simulations show this pathway is viable for primary stars of 12-16 solar masses.
- The hydrogen mass at explosion matches observational constraints for SNe IIb.

## Abstract

From stellar evolution simulations (using MESA) we conclude that the fatal common envelope evolution (CEE) channel for the formation of Type IIb core collapse supernova (SN IIb) progenitors can indeed account for some SNe IIb. In the fatal CEE channel for SNe IIb a low mass main sequence secondary star inspirals inside the giant envelope of the massive primary star and removes most of the giant envelope before it merges with the giant core. The key ingredient of the scenario studied here is that the tidally destroyed secondary star forms a new giant envelope. The mass-loss process in a wind during the evolution from the merger process until core collapse, i.e., until the explosion, leaves little hydrogen mass at explosion as inferred from observations of SNe IIb. In the case of a massive primary star with a zero age main sequence mass of M(ZAMS)=16Mo that during its giant phase swallows a main sequence star of mass M2=0.5Mo, we find at explosion a hydrogen mass of M(H)=0.02-0.09Mo, depending on the rotation we assume. We find similar values for M(ZAMS)=12Mo.