Double Bangs from New Physics in IceCube

TL;DR

This paper explores how IceCube can detect new physics involving heavy neutrinos through distinctive double-bang events caused by atmospheric neutrinos, providing a novel way to constrain models with sterile neutrinos.

Contribution

It introduces the concept of using double-bang event topology at IceCube to search for heavy neutrinos from new physics models, offering a new experimental signature.

Findings

IceCube can already set competitive constraints on GeV-scale sterile neutrino models.

Double-bang events have a very low background, making them a clean signal for new physics.

Atmospheric neutrinos can produce detectable double-bang signatures if heavy neutrinos are involved.

Abstract

A variety of new physics models allows for neutrinos to up-scatter into heavier states. If the incident neutrino is energetic enough, the heavy neutrino may travel some distance before decaying. In this work, we consider the atmospheric neutrino flux as a source of such events. At IceCube, this would lead to a "double-bang" (DB) event topology, similar to what is predicted to occur for tau neutrinos at ultra-high energies. The DB event topology has an extremely low background rate from coincident atmospheric cascades, making this a distinctive signature of new physics. Our results indicate that IceCube should already be able to derive new competitive constraints on models with GeV-scale sterile neutrinos using existing data.