$B^0-\overline{B^0}$ mixing in the $U(1{)}_X$SSM

Abstract

$U(1{)}_X$SSM is a non-universal Abelian extension of the Minimal Supersymmetric Standard Model (MSSM) and its local gauge group is extended to $SU(3{)}_C\times SU(2{)}_L\times U(1{)}_Y\times U(1{)}_X$. Based on the latest data of neutral meson mixing and experimental limitations, we investigate the process of $B^0-\overline{B^0}$ mixing in $U(1{)}_X$SSM. Using the effective Hamiltonian method, the Wilson coefficients and mass difference $△m_B$ are derived. The abundant numerical results verify that $v_S,M_D^2,{\lambda }_C,\mu ,M_2,\tan \beta ,g_{YX},M_1$ and ${\lambda }_H$ are sensitive parameters to the process of $B^0-\overline{B^0}$ mixing. With further measurement in the experiment, the parameter space of the $U(1{)}_X$SSM will be further constrained during the mixing process of $B^0-\overline{B^0}$.