Annual modulation of cosmic relic neutrinos

The cosmic neutrino background (CνB), produced about one second after the big bang, permeates the Universe today. New technological advancements make neutrino capture on beta-decaying nuclei (NCB) a clear path forward towards the detection of the CνB. We show that gravitational focusing by the Sun c...

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Bibliographic Details
Main Authors: Safdi, Benjamin R., Lisanti, Mariangela, Formaggio, Joseph A., Spitz, Joshua B.
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:English
Published: American Physical Society 2014
Online Access:http://hdl.handle.net/1721.1/88672
https://orcid.org/0000-0002-3757-9883
Description
Summary:The cosmic neutrino background (CνB), produced about one second after the big bang, permeates the Universe today. New technological advancements make neutrino capture on beta-decaying nuclei (NCB) a clear path forward towards the detection of the CνB. We show that gravitational focusing by the Sun causes the expected neutrino capture rate to modulate annually. The amplitude and phase of the modulation depend on the phase-space distribution of the local neutrino background, which is perturbed by structure formation. These results also apply to searches for sterile neutrinos at NCB experiments. Gravitational focusing is the only source of modulation for neutrino capture experiments, in contrast to dark-matter direct-detection searches where the Earth’s time-dependent velocity relative to the Sun also plays a role.