Probing the R-parity violating supersymmetric effects in Bc→ J/ψℓ-νℓ,ηcℓ-νℓ and Λb→Λcℓ-νℓ decays

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Motivated by recent RD, RD* and Rⱼ/ψ anomalies in B→ Dℓ- νℓ, B→ D*ℓ- νℓ and Bc→ J/ψℓ- νℓ decays, respectively, we study possible R-parity violating supersymmetric effects in Bc→ J/ψℓ- νℓ,ηcℓ- νℓ and Λb → Λc ℓ- νℓ decays, which are also induced by b→ c ℓ- νℓ at quark level. We find that (I) the constrained slepton exchange couplings λᵢ₃₃λ'*ᵢ₂₃ involving in b→ c τ- ντ transition from relevant latest experimental data still have quite large effects on all (differential) branching ratios and the normalized forward-backward asymmetries of the exclusive semileptonic b→ c τ- ντ decays as well as the ratios of the (differential) branching ratios; (II) after satisfying the data of RD and RD*, the upper limit of Rⱼ/ψ, Rηc and RΛc could be increased by 10%, 112% and 24%, respectively, from their upper limits of the Standard Model predictions by the λᵢ₃₃λ'*ᵢ₂₃ couplings. The results in this work could be used to probe R-parity violating effects and will correlate with searches for direct supersymmetric signals at the running LHCb and the forthcoming Belle-II.