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Study on $ν_μ$, $ν_τ$ Decays and CP-Non Invariance at Early Epoch of the Universe

Wu-Sheng Dai·Song Gao·Xue-Qian Li
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Abstract

We study the $ν_μ$ and $ν_τ$ decays in the early epoch of the universe. If $m_{ν_τ}>2m_e$, there would be a CP asymmetry between $ν_τ\rightarrow e^++e^-+ν_e$ and $\barν_τ \rightarrow e^++e^-+\barν_e$. The resultant CP non-invariance is a function of temperature and density and can reach $10^{-7}$ for a reasonable temperature range, but it is noticed that if $m_{ν_τ}>2m_μ\sim 200$ MeV, the CP non-invariance can be much larger.

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Wu-Sheng Dai, Song Gao, Xue-Qian Li. 1996-05-21. Study on $ν_μ$, $ν_τ$ Decays and CP-Non Invariance at Early Epoch of the Universe. https://arxiv.org/abs/hep-ph/9605366

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