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Cosmological constraints on R-parity violation from neutrino decay

Gautam Bhattacharyya·Subhendu Rakshit·Amitava Raychaudhuri
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Abstract

If the neutrino mass is non-zero, as hinted by several experiments, then R-parity-violating supersymmetric Yukawa couplings can drive a heavy neutrino decay into lighter states. The heavy neutrino may either decay radiatively into a lighter neutrino, or it may decay into three light neutrinos through a Z-mediated penguin. For a given mass of the decaying neutrino, we calculate its lifetime for the various modes, each mode requiring certain pairs of R-parity-violating couplings be non-zero. We then check whether the calculated lifetimes fall in zones allowed or excluded by cosmological requirements. For the latter case, we derive stringent new constraints on the corresponding products of R-parity-violating couplings for given values of the decaying neutrino mass.

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Gautam Bhattacharyya, Subhendu Rakshit, Amitava Raychaudhuri. 2000-06-30. Cosmological constraints on R-parity violation from neutrino decay. https://doi.org/10.1103/physrevd.62.093007

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