Lepton flavor violating Λ${}_b$→Λℓ${}_1$ℓ${}_2$ decay

Inspired by the recent hints of lepton flavor universality violation in b→sℓℓ and b→cℓν transitions, we study lepton flavor violating exclusive Λ${}_b$→Λℓ${}_1^{+}$ℓ${}^{\text{â}}\text{ˆ}{\text{’}}_2$ (ℓ${}_1$≠ℓ${}_2$) decay, which is forbidden in the Standard Model. Starting from a general effective Hamiltonian for a b→sℓ${}_1^{+}$ℓ${}^{\text{â}}\text{ˆ}{\text{’}}_2$ transition that includes vector and axial-vector operators, and scalar and pseudo-scalar operators, we derive a two-fold decay distribution of Λ${}_b$→Λℓ${}_1^{+}$ℓ${}^{\text{â}}\text{ˆ}{\text{’}}_2$. The distribution helps us to construct the differential branching ratio and the lepton-side forward–backward asymmetry, which are studied in a vector leptoquark model. The parameter space of the vector leptoquark model is constrained by low energy observables.