On the absence of nova shells

TL;DR

This study used wide field Halpha+N[II] observations to search for nova shells around 15 cataclysmic variables, finding none and thus setting a lower limit of 13,000 years on their nova recurrence times.

Contribution

It provides the first systematic search for nova shells around high-mass transfer cataclysmic variables and establishes a lower recurrence time limit.

Findings

No nova shells detected around the 15 studied systems.

Sets a lower limit of 13,000 years on nova recurrence times.

Suggests high-mass transfer CVs may have longer recurrence intervals.

Abstract

We present our wide field Halpha+N[II] observations of 15 cataclysmic variables to search for remnant nova shells. Such shells have been found around other cataclysmic variables that were hitherto not known as novae. Our candidates were selected as objects in the period regime of high-mass transfer systems that experience - at least occasionally - low mass transfer rates. The fact that we find no indication of a nova shell in any of these systems allows us to set a lower limit of 13000 years to the recurrence time of these objects.