Abstract
We present a full angular distribution of the four body Λb → Λ(→ N π)ℓ+ℓ− decay where the leptons are massive and the Λb is unpolarized, in an operator basis which includes the Standard Model operators, new vector and axial-vector operators, and scalar and pseudo-scalar operators. The angular coefficients are expressed in terms of transversity amplitudes. We study several Λb → Λ(→ pπ)τ +τ − observables in the Standard Model and in the presence of the new operators. For our numerical analysis, we use the form factors from lattice QCD calculations.
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Das, D. On the angular distribution of Λb → Λ(→ N π)τ +τ − decay. J. High Energ. Phys. 2018, 63 (2018). https://doi.org/10.1007/JHEP07(2018)063
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DOI: https://doi.org/10.1007/JHEP07(2018)063