Study of FCNC mediated Z boson effectin the semileptonic rare baryonic decays Λ b → Λl + l -
Department of Physics, National Tsing Hua University, Hsinchu, Taiwan 300
2 University of Hyderabad, School of Physics, 500 046, Hyderabad, India
We study the effect of the FCNC mediated Z boson in the rare semileptonic baryonic decays Λ b → Λl + l -. We consider the model where the standard model fermion sector is extended by an extra vector-like down quark, as a consequence of which it allows for CP-violating Z mediated flavor changing neutral current at the tree level. We find that due to this non-universal Zbs coupling, the branching ratios of the rare semileptonic Λ b decays are enhanced reasonably from their corresponding standard model values and the zero point of the forward-backward asymmetry for Λ b → Λμ + μ - is shifted to the left.
© Springer-Verlag, 2006