The invariant and helicity amplitudes in the transitions ${\mathrm{\Lambda }}_b\to {\mathrm{\Lambda }}^{\ast }({\frac{1}{2}}^{\pm },{\frac{3}{2}}^{\pm })+J\mathrm{/}\psi$

We present results for the invariant and helicity amplitudes in the transitions ${\mathrm{\Lambda }}_b\to {\mathrm{\Lambda }}^{(\ast )}(J^P)+J\mathrm{/}\psi$ where the ${\mathrm{\Lambda }}^{(\ast )}(J^P)$ are $\mathrm{\Lambda }(sud)$-type ground and excited states with $J^P$ quantum numbers $J^P={\frac{1}{2}}^{\pm },{\frac{3}{2}}^{\pm }$. The calculations are performed in the framework of a covariant confined quark model. This analysis is important for the identification of the hidden charm pentaquark states $P_c^{+}(4380)$ and $P_c^{+}(4450)$ which were discovered by the LHCb Coll. We also discuss the possible New Physics effects in the exclusive decays $\bar{B}^0 \to D^{(\ast)} \tau^- \bar{\nu}_{\tau}$. We extend the Standard Model by taking into account right-handed vector (axial), left- and right-handed (pseudo)scalar, and tensor current contributions. The $\bar{B}^0 \to D^{(\ast)}$transitionformfactorsarecalculatedinthefullkinematic$q^2$ range by employing a covariant quark model.