Implication of $R_{D^{(\ast )}}$ anomalies on semileptonic decays of ${\Sigma }_b$ and ${\Omega }_b$ baryons

Abstract

The flavor changing decays of heavy bottom quarks to the corresponding lighter quarks ($u$, $c$ and $s$) in various $B$-meson decays via charged current and neutral current semileptonic transitions have emerged as promising candidates to explore the physics beyond the standard model. Experimentally the lepton flavor universality violation in $b\to (c,u)l\nu$ and $b\to s{l}^{+}{l}^{-}$ transitions have been reported to a higher precision. The measurements of the lepton flavor violating ratios such as $R_{D^{(\ast )}}$, $R_{J/\Psi }$ and $R_{K^{(\ast )}}$ are observed to deviate from the standard model expectations at the level of $1.4\sigma$, $2.5\sigma$, $1.5\sigma$, $2.4\sigma$ and $2.2\sigma$ respectively. Motivated by these anomalies, we investigate the lepton flavor universality violation in ${\Sigma }_b\to {\Sigma }_{c}l\nu$ and ${\Omega }_b\to {\Omega }_{c}l\nu$ decays. We follow a model independent effective field theory formalism and study the implications of $R_{D^{(\ast )}}$ anomalies on ${\Sigma }_b\to {\Sigma }_c\tau \nu$ and ${\Omega }_b\to {\Omega }_c\tau \nu$ decay modes. We give predictions of various physical observables such as the ratio of branching ratios, total differential decay rate, forward-backward asymmetry, lepton side polarization fraction and convexity parameter within the standard model and within various new physics scenarios.

Comments: 15 pages, 8 figures