Study of semileptonic decay B→ρl+l- in non-universal Z' model

Abstract

Exclusive B decays based on <i>b → s(d)</i> transition provide useful information about the various parameters in the standard model (SM) and also offer a great possibility for searching the new physics (NP). Although, there exists a lot of precise results on <i>b → sl⁺l^-</i> induced processes, there is lack of sufficient data for <i>b → dl⁺l^-</i> induced decays. From experimental evidences it is found that the B meson decays which have the quark level transition <i>b → d</i> have small branching ratio <i>O</i>(10^-8) and large CP asymmetry. So, B meson decays induced by <i>b → d</i> flavour changing neutral current (FCNC) transitions are very challenging to probe the quark-flavour sector of the standard model (SM) and also to search NP. To the best of our knowledge, the decay mode <i>B → ρl⁺l^-</i> (<i>l = τ, µ, e</i>) has not been studied experimentally so far. In this work, we are interested to study theoretically <i>B → ρl⁺l^-</i> decay which proceeds via <i>B → dl⁺l^-</i> transition at the quark level. We study the CP violation asymmetry in the exclusive decay channel <i>B → dl⁺l^-</i> in a non-universal Z' model. We find a significant deviation from the SM value of CP violation asymmetry for this decay which provides a clear conjecture for NP arising from Z' gauge boson.