Impact of binary interactions on the diffuse supernova neutrino background

TL;DR

This study examines how binary star interactions, such as mergers and mass transfer, influence the predicted flux of diffuse supernova neutrinos, revealing a potential 15-20% increase in detection rates and highlighting significant uncertainties.

Contribution

It introduces stellar population synthesis models that incorporate binary interactions to refine predictions of the diffuse supernova neutrino background.

Findings

Detection rates increased by 15%-20% with binary effects.

Uncertainty due to rapid rotation in merger remnants is significant.

Potential enhancement ranges from a few percent to 75%.

Abstract

Binary interactions, especially mass transfer and mergers, can strongly influence the evolution of massive stars and change their final properties and the occurrence of supernovae. Here, we investigate how binary interactions affect predictions of the diffuse flux of neutrinos. By performing stellar population syntheses including prescriptions for binary interactions, we show that the resulting detection rates of the diffuse supernova neutrino background is enhanced by 15%-20% compared to estimates without binary considerations. A source of significant uncertainty arises due to the presently sparse knowledge of the evolution of rapidly rotating carbon-oxygen cores, especially those created as a result of mergers near the white dwarf to core collapse boundary. The enhancement effect may be as small as a few percent if the effects of rotation in postmerger systems are neglected, or as large as 75% if trends are extrapolated. Our estimates serve to highlight that binary effects can be important.