Visibility stacking in the quest for SNIa radio emission

TL;DR

This paper introduces a method called visibility stacking to enhance radio observations of type Ia supernovae, setting new upper limits on their radio luminosity and companion star mass loss rates, with implications for supernova progenitor models.

Contribution

The paper presents a novel visibility stacking technique for radio interferometry data, enabling deeper composite imaging of supernovae and improved constraints on their progenitor systems.

Findings

Set a new upper limit on SNIa radio luminosity of 1.2x10^{25} erg/s/Hz.

Constrained the average companion stellar wind mass loss rate to 1.3x10^{-7} M_sun/yr.

Ruled out intermediate and high mass companions in the single degenerate scenario.

Abstract

We describe the process of stacking radio interferometry visibilities to form a deep composite image and its application to the observation of transient phenomena. We apply "visibility stacking" to 46 archival Very Large Array observations of nearby type Ia supernovae (SNeIa). This new approach provides an upper limit on the SNIa ensemble peak radio luminosity of 1.2x10^{25}erg/s/Hz at 5GHz, which is 5-10 times lower than previously measured. This luminosity implies an upper limit on the average companion stellar wind mass loss rate of 1.3x10^{-7}M_o/yr. This mass loss rate is consistent with the double degenerate scenario for SNeIa and rules out intermediate and high mass companions in the single degenerate scenario. In the era of time domain astronomy, techniques such as visibility stacking will be important in extracting the maximum amount of information from observations of populations of short lived events.