Cosmological bound on Dirac neutrino mass via. gamma. gamma. r arrow. pi. sup 0 r arrow. nu. nu

Journal Article · Fri Nov 15 00:00:00 EST 1991 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.44.3345· OSTI ID:6159861

Lam, W P; Ng, K ^[1]

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1. Institute of Physics, Academia Sinica, Taipei, Taiwan 11529 (Republic of China)

Cosmological production of massive right-handed Dirac neutrinos via the pion-pole mechanism, {gamma}{gamma}{r arrow}{pi}{sup 0}{r arrow}{nu}{bar {nu}}, is considered. Using the upper bound on the effective number of neutrino species during primordial nucleosynthesis, we obtain a limit on the branching ratio for the decay {pi}{sup 0}{r arrow}{nu}{bar {nu}}, {ital R}{lt}2.9{times}10{sup {minus}13}, and an upper bound on the mass of Dirac neutrinos, {ital m}{sub {nu}}{lt}420 keV.

• OSTI ID: 6159861
• Journal Information: Physical Review, D (Particles Fields); (United States), Vol. 44:10; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
COSMOLOGICAL MODELS
NUCLEOSYNTHESIS
NEUTRINOS
MASS
ANNIHILATION
BRANCHING RATIO
DECAY
DIRAC EQUATION
PARTICLE PRODUCTION
PHOTON-PHOTON INTERACTIONS
PIONS NEUTRAL
STANDARD MODEL
SUPERNOVAE
BASIC INTERACTIONS
BOSONS
DIFFERENTIAL EQUATIONS
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
EQUATIONS
ERUPTIVE VARIABLE STARS
FERMIONS
HADRONS
INTERACTIONS
LEPTONS
MASSLESS PARTICLES
MATHEMATICAL MODELS
MESONS
PARTIAL DIFFERENTIAL EQUATIONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PIONS
PSEUDOSCALAR MESONS
STARS
SYNTHESIS
UNIFIED GAUGE MODELS
VARIABLE STARS
WAVE EQUATIONS
661300* - Other Aspects of Physical Science- (1992-)
662430 - Properties of Leptons- (1992-)