One loop correction to $Z\rightarrow \nu\nu$ in the Minimal R-symmetric Supersymmetric Standard Model

Abstract

We analyze the one loop correction to $Z\rightarrow \nu\nu$ decay in framework of Minimal R-symmetric Supersymmetric Standard Model(MRSSM) in detail with normal and inverse neutrino mass orderings, as a function of $\tan\beta$, Dirac mass parameters $M_D^W$ and $\mu_u(\mu_d)$, slepton mass $m_l$ that parameterize the mass matrices. The numerical results indicate that the branching ratio for $Z\rightarrow \nu\nu$ decay is compatible with the experimental measurement and the SM expectation at $2\sigma$ level. For inverse neutrino mass ordering, the prediction exceeds the SM expectation at $1\sigma$ level. The prediction on $Br(Z\rightarrow \nu\nu)$ increases proportionally to $\tan\beta$ and inversely proportionally to $m_l$. For normal neutrino mass ordering, the peak value of the prediction on $Br(Z\rightarrow \nu\nu)$ exceeds the SM expectation at $1\sigma$ level.