Model Independent Analysis of $$\bar{B}^* \rightarrow P l \bar{\nu }_l $$ Decay Processes

A spectacular deviation of Standard Model (SM) value of lepton nonuniversality (LNU) parameters \(\big (R_D, R_{D^*}, R_K, R_{K*}, R_{J/\psi }\big )\) from their experimental one, provides a clear hint for the presence of new physics (NP) beyond the SM. In this context, we have studied the effect of NP in the semileptonic \(\bar{B}^* \rightarrow P l \bar{\nu }_l\) decay process in a model independent way. In this approach, we considered the NP to have scalar, vector, and tensor type of couplings and treated the new Wilson coefficients as complex quantities in our analysis. We constrained the parameter space of new couplings using the measured values of \(\mathrm{Br(B}_{u}^+ \rightarrow \tau ^+ \nu _\tau \mathrm{)}\), \(\mathrm{Br(B} \rightarrow \pi \tau \bar{\nu }_\tau \mathrm{)}\), \(R_\pi ^l\) for \(b\rightarrow u l \bar{\nu }_l\) processes and \(\mathrm{Br(B}_{c}^+ \rightarrow \tau ^+ \nu _\tau {)}\), \(R_{D^{(*)}}\) and \(R_{J/\psi }\) observables for \(b \rightarrow c l \bar{\nu }_l\) processes. Using the constrained parameters, we analyzed the \(q^2\) variation of branching ratio, forward-backward asymmetry, and LNU parameters of \(\bar{B}^* \rightarrow P l \bar{\nu }_{l}\) process, in the context of NP.