Polarized Λb baryon decay to pπ and a dilepton pair

Autor: Diganta Das, Ria Sain
Rok vydání: 2021
Předmět:
Zdroj: Physical Review D. 104
ISSN: 2470-0029
2470-0010
DOI: 10.1103/physrevd.104.013002
Popis: The recent anomalies in $b\ensuremath{\rightarrow}s{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ transitions could originate from some new physics beyond the Standard Model. Either to confirm or to rule out this assumption, more tests of $b\ensuremath{\rightarrow}s{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ transition are needed. Polarized ${\mathrm{\ensuremath{\Lambda}}}_{b}$ decay to a $\mathrm{\ensuremath{\Lambda}}$ and a dilepton pair offers a plethora of observables that are suitable to discriminate new physics from the Standard Model. In this paper, we present a full angular analysis of a polarized ${\mathrm{\ensuremath{\Lambda}}}_{b}$ decay to a $\mathrm{\ensuremath{\Lambda}}(\ensuremath{\rightarrow}p\ensuremath{\pi}){\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$ final state. The study is performed in a set of the operator where the Standard Model operator basis is supplemented with its chirality flipped counterparts, and new scalar and pseudoscalar operators. The full angular distribution is calculated by retaining the mass of the final state leptons. At the low hadronic recoil, we use the heavy quark effective theory framework to relate the hadronic form factors which lead to simplified expression of the angular observables where short- and long-distance physics factorize. Using the factorized expressions of the observables, we construct a number of test of short- and long-distance physics including null tests of the Standard Model and its chirality flipped counterparts that can be carried out using experimental data.
Databáze: OpenAIRE