(B)over-bar → D(*)τ(ν)over-bar excesses in ALRSM constrained form B, D decays and D0 - (D)over-bar0 mixing

Recent experimental results from the LHCb, BaBar and Belle collaborations on the semitauonic decays of B meson, (B) over bar -> D-(*) tau(nu) over bar, showing a significant deviation from the Standard Model (SM), hint towards a new physics scenario beyond the SM. In this work, we show that these enhanced decay rates can be explained within the framework of E-6 motivated Alternative Left-Right Symmetric Model (ALRSM), which has been successful in explaining the recent CMS excesses and has the feature of accommodating high scale leptogenesis. The R-parity conserving couplings in ALRSM can contribute universally to both (B) over bar -> D tau(nu) over bar and (B) over bar -> D-(*) tau(nu) over bar via the exchange of scalar leptoquarks. We study the leptonic decays D-s(+) -> tau(+) (nu) over barB(+) -> tau(+)(nu) over bar, D+ -> tau(+) (nu) over bar and D-0 - (D) over bar (0) mixing to constrain the couplings involved in explaining the enhanced B decay rates and we find that ALRSM can explain the current experimental data on R (D-(*)) quite well while satisfying these constraints.