# Why Are Peculiar Type Ia Supernovae More Likely to Show the Signature of a Single-degenerate Model?

## TL;DR

This paper proposes a universal spin-up/spin-down model for Type Ia supernovae, explaining why peculiar SNe Ia are more likely to exhibit signatures of the single-degenerate progenitor scenario based on initial white dwarf mass.

## Contribution

It introduces a spin-up/spin-down model linking initial WD mass to SD signatures, explaining observational differences among SNe Ia.

## Key findings

- More massive initial WDs have shorter spin-down timescales.
- Hybrid carbon-oxygen-neon WDs are more likely to show SD signatures.
- The model accounts for the diversity in observed SNe Ia signatures.

## Abstract

Although type Ia supernovae (SNe Ia) are very useful in many astrophysical fields, their exact progenitor nature is still unclear. A basic method to distinguish the different progenitor models is to search the signal from the single degenerate (SD) model, e.g. the signal for the existence of a non-degenerate companion before or after supernova explosion. Observationally, some SNe Ia show such signal, while the others do not. Here, we propose a universal model to explain these observations based on the spin-up/spin-down model, in which a white dwarf (WD) will experience a spin-down phase before supernova explosion, and the spin-down timescale is determined by its initial mass, i.e. the more massive the initial WD, the shorter the spin-down timescale and then the more likely the SN Ia to show the SD signature. Therefore, our model predicts that the SNe Ia from hybrid carbon-oxygen-neon WDs are more likely to show the SD signature observationally, as some peculiar SNe Ia showed.