Lepton flavour violating $${\Lambda }_{{b}}$$ decays in non-universal $${Z}^{\prime }$$ model

Abstract

Motivated by the recent LHCb results of lepton flavour violation on $$b\rightarrow s$$ b → s and $$b\rightarrow c$$ b → c transitions we study the lepton flavour violating (LFV) baryonic decays $${\Lambda }_{b}\rightarrow {\Lambda }l_{i}^{+}l_{j}^{-}$$ Λ b → Λ l i + l j - in non-universal $$Z^{\prime }$$ Z ′ model. We discuss the two-fold decay distribution of $${\Lambda }_{b}\rightarrow {\Lambda }l_{i}^{+}l_{j}^{-}$$ Λ b → Λ l i + l j - decays in terms of transversity amplitudes. From this distribution we study the differential branching ratio and lepton side forward-backward asymmetry in new physics (NP). The predicted values of the observables are very interesting and that might emboss the footprints of NP more aesthetically.

Imprints of new physics in Λb → Λ∗l+l− decay in nonuniversal Z′ model

“…It indicates that the higher value of NP couplings flip the nature of 𝐴 𝐹𝐵 faster. This result agrees with our previous work [67]. Another very exciting thing we observe that the zero crossing is absent for tau channel, it has negative value throughout the whole kinematic region.…”

Impact of non-universal $${{Z}}^{{'}}$$ in the lepton flavour violating $${{B}}\left( {{B}}_{{{s}}} \right) {\rightarrow }{{K}}^{{*}}\left( {\varphi } \right) {{l}}_{{{1}}}^{{-}}{{l}}_{{{2}}}^{{+}}$$ decays

“…We have calculated the branching ratio values, forward backward asymmetries and longitudinal polarization asymmetries for these decays. In our last work, we have constrained the LFV leptonic couplings [57] which are applied here. Our plots show that the 2 nd scenario provides higher values of the observables which offer a clear cut signature of NP in these LFV decays.…”

“…In this work, we study the differential branching ratio, forward backward asymmetry and longitudinal polarization for 𝑏 → 𝑠 transition. In our previous work [57], we have studied lepton flavour violating Λ 𝑏 decays and constrained the LFV leptonic couplings from the recent bound of various LFV decays of same quark transition. The LFV quark couplings are taken from refs [39,58] and are recorded in Table-1.…”

“…Another promising tool to explore NP in these decays is the lepton side forward-backward asymmetries. The sensitiveness of the observable on the LFV Λ 𝑏 baryon decays has been studied in the references [40,57]. We have studied the variation of forward-backward asymmetries in the 𝑍 ′ model in the allowed 𝑞 2 region in Fig.…”