Wave-driven outbursts and variability of low-mass supernova progenitors

TL;DR

This study uses hydrodynamic simulations to explore how wave-driven processes affect low-mass supernova progenitors, revealing significant stellar expansion and brightness changes but limited direct mass loss, impacting supernova observations.

Contribution

It provides new insights into wave heating effects on low-mass SN progenitors, especially regarding stellar expansion and luminosity changes prior to explosion.

Findings

Wave heating causes large stellar expansion and luminosity brightening.

Wave heating does not directly drive mass loss in models.

Progenitors may appear brighter and larger before supernova.

Abstract

In a substantial number of core-collapse supernovae, early-time interaction indicates a dense circumstellar medium (CSM) that may be produced by outbursts from the progenitor star. Wave-driven mass loss is a possible mechanism to produce these signatures, with previous work suggesting this mechanism is most effective for low mass ($ \sim \! 11 \, M_\odot$) SN progenitors. Using one-dimensional hydrodynamic simulations with MESA, we study the effects of this wave heating in SN progenitors of masses $M_{\rm ZAMS} = 10-13\, M_{\odot}$. This range encompasses stars that experience semi-degenerate, central neon burning and more degenerate, off-center neon ignition. We find that central Ne ignition at $M_{\rm ZAMS} = 11\, M_{\odot}$ produces a burst of intense wave heating that transmits $\sim10^{47}$ erg of energy at $10$ years before core collapse, whereas other masses experience smaller levels of wave heating. Wave heating does not hydrodynamically drive mass loss in any of our models and is unlikely to produce a very massive CSM on its own. However, wave heating can cause large radial expansion (by more than an order of magnitude), photospheric cooling, and luminosity brightening by up to $\sim 10^6\, L_{\odot}$ in hydrogen-poor stripped star models. Some type Ib/c progenitors could drastically change their appearance in the final years of their lives, with brightness in visual bands increasing by nearly 3 mags. Moreover, interaction with a close binary companion could drive intense mass loss, with implications for type Ibn and other interaction-powered SNe.