The circumstellar environment of pre-SN Ia systems

TL;DR

This paper investigates the circumstellar debris around potential Type Ia supernova progenitors, highlighting how recurrent nova shells could create observable non-spherical shells of gas and dust that influence supernova environments.

Contribution

It proposes a model for the formation and distribution of circumstellar shells from recurrent nova systems as potential Type Ia supernova progenitors.

Findings

Recurrent nova shells form non-spherical, thin shells of gas and dust.

These shells can be observed as radio flashes around 100 years after a supernova.

Such shells influence the supernova environment and its observational signatures.

Abstract

Here we explore the possible preexisting circumstellar debris of supernova type Ia systems. Classical, symbiotic and recurrent novae all accrete onto roughly solar mass white dwarfs from main sequence or Mira type companions and result in thermonuclear runaways and expulsion of the accreted material at high velocity. The expelled material forms a fast moving shell that eventually slows to planetary nebula expansion velocities within several hundred years. All such systems are recurrent and thousands of shells (each of about 0.001 Mo) snow plough into the environment. As these systems involve common envelope binaries the material is distributed in a non-spherical shell. These systems could be progenitors of some SN Ia and thus explode into environments with large amounts of accumulated gas and dust distributed in thin non-spherical shells. Such shells should be observable around 100 years after a SN Ia event in a radio flash as the SN Ia debris meets that of the ejected material of the systems previous incarnation.