b → cτ(v)over-bar decay in supersymmetry with R-parity violation

In past years, several hints of lepton flavor universality (LFU) violation have emerged from the b -> c tau(v) over bar and b -> sl(+)l(-) data. More recently, the Belle Collaboration has reported the first measurement of the D* longitudinal polarization fraction in the B -> D*tau(v) over bar decay. Motivated by this intriguing result, along with the recent measurements of R-J/psi and tau polarization, we present the study of b -> c tau(v) over bar decays in supersymmetry (SUSY) with R-parity violation (RPV). We consider B -> D-(*())tau(v) over bar , B-C -> eta(C)tau(v) over bar, B-C -> J/psi tau(v) over bar and Lambda(b) -> Lambda(C)tau(v) over bar modes and focus on the branching ratios, LFU ratios, forward-backward asymmetries, polarizations of daughter hadrons, and the tau lepton. The RPV SUSY was capable of explaining the R-D(*) anomalies at the 2 sigma level, after taking into account various flavor constraints. In the allowed parameter space, the differential branching fractions and LFU ratios are largely enhanced by the SUSY effects, especially in the large dilepton invariant mass region. Moreover, a lower bound B(B+ -> K(+)v (v) over bar) > 7.37 x 10(-6) is obtained. These observables could provide testable signatures at the high-luminosity LHC and SuperKEKB, and correlate with direct searches for SUSY.