Constraining the Self-Interacting Neutrino Interpretation of the Hubble Tension

Journal Article · 07 November 2019 · Physical Review Letters

DOI: https://doi.org/10.1103/PhysRevLett.123.191102 · OSTI ID:1545086

Blinov, Nikita  ^[1]; Kelly, Kevin J.  ^[1]; Krnjaic, Gordan  ^[1]; McDermott, Samuel D.  ^[1]

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1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

Large, nonstandard neutrino self-interactions have been shown to resolve the ~4σ tension in Hubble constant measurements and a milder tension in the amplitude of matter fluctuations. Herein we demonstrate that interactions of the necessary size imply the existence of a force carrier with a large neutrino coupling (>10^-4) and mass in the keV–100 MeV range. This mediator is subject to stringent cosmological and laboratory bounds, and we find that nearly all realizations of such a particle are excluded by existing data unless it carries spin 0 and couples almost exclusively to $$τ$$-flavored neutrinos. Furthermore, we find that the light neutrinos must be Majorana particles, and that a UV-complete model requires a nonminimal mechanism to simultaneously generate neutrino masses and appreciable self-interactions.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-07CH11359
• OSTI ID: 1545086
• Report Number(s): arXiv:1905.02727; FERMILAB-PUB-19-175-A-T; arXiv:1905.02727v2; PRLTAO; oai:inspirehep.net:1733842
• Journal Information: Physical Review Letters, Vol. 123, Issue 19; ISSN 0031-9007
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English