Constraints on radiative decay of massive neutrinos

Journal Article · Tue Sep 15 04:00:00 EDT 1992 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.46.2362· OSTI ID:7275146

Wang, B ^[1]

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1. Department of Astronomy and Physics, and Center for Particle Astrophysics, University of California, Berkeley, California 94720 (United States)

Recent {beta}-decay experiments provide evidence for the existence of neutrinos with a mass of 17 keV. If they do exist, they should decay into lighter particles in order to avoid overclosing the Universe. Radiative decay may leave an imprint on the relic radiation from the big bang, and energy injection into the cosmic microwave background radiation should have observational consequences. In particular, the limits recently obtained on the {ital y} distortion of the blackbody spectrum of the cosmic microwave background provide stringent constraints on the radiative-decay properties of these neutrinos. We have found that the photon branching ratio has to be {ital B}{sub {gamma}}{approx lt}10{sup {minus}5} for the neutrino lifetime {tau}{congruent}10{sup 10}--10{sup 11} s. For {tau}{approx gt}10{sup 11} s, {ital B}{sub {gamma}} is constrained by the upper limits on the extragalactic background radiation at optical and UV wavelengths; the upper limit on {ital B}{sub {gamma}} decreases to about 10{sup {minus}6} at {tau}{congruent}10{sup 12} s.

• OSTI ID: 7275146
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 46:6; ISSN PRVDA; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

662370* -- Decays of Leptons-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BACKGROUND RADIATION
BLACKBODY RADIATION
BOSONS
BRANCHING RATIO
COSMIC NEUTRINOS
COSMIC RADIATION
DECAY
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
IONIZING RADIATIONS
KEV RANGE
KEV RANGE 10-100
LEPTONS
LIFETIME
MASS
MASSLESS PARTICLES
MICROWAVE RADIATION
NEUTRINOS
PARTICLE DECAY
PHOTONS
RADIATIONS
RADIATIVE DECAY
RELICT RADIATION
ULTRAVIOLET RADIATION
UNIVERSE