A Possible Detection of the Cosmic Antineutrino Background in the Presence of Flavor Effects

TL;DR

This paper explores the potential to detect the cosmic antineutrino background using holmium-163, analyzing how neutrino flavor effects influence the detection rate and emphasizing the importance of future calorimetric measurements.

Contribution

It provides a detailed calculation of relic antineutrino capture rates on holmium-163 considering neutrino flavor effects and mass hierarchies, highlighting their significance.

Findings

Flavor effects significantly impact detection rates.

Calorimetric detection of cosmic antineutrinos may be feasible.

Neutrino mass hierarchy influences capture rates.

Abstract

Lusignoli and Vignati have recently pointed out that it is in principle possible to directly detect the cosmic antineutrino background by using the rather stable isotope holmium-163 as a target, which can decay into dysprosium-163 via electron capture (EC) with a very small energy release. In this paper we calculate the rate of the relic antineutrino capture on holmium-163 nuclei against the corresponding EC decay rate by taking account of different neutrino mass hierarchies and reasonable values of theta_13. We show that such flavor effects are appreciable and even important in some cases, and stress that a calorimetric measurement of the cosmic antineutrino background might be feasible in the far future.