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$B \to D^{(*)} τ ν_{τ}$ decay properties with the relativistic independent quark model

Sonali Patnaik ^*, Lopamudra Nayak ^†, and Sanjay Kumar Swain ^‡

National Institute of Science Education and Research, An OCC of Homi Bhabha National Institute, Bhubaneswar, Odisha, India

^*Contact author: sonali_patnaik@niser.ac.in
^†Contact author: lopalmnayak@niser.ac.in
^‡Contact author: sanjay@niser.ac.in

Phys. Rev. D 112, 033003 – Published 13 August, 2025

DOI: https://doi.org/10.1103/xtcf-2vw9

Abstract

In this work we compute the branching fraction of $B \to D^{(*)} τ ν_{τ}$ and $B_{s} \to D_{s}^{(*)} τ ν_{τ}$ within the relativistic independent quark model, emphasizing the harmonic potential model-dependent analysis of these decay channels in the precision flavor physics era. Considering the experimental observation of longitudinal $τ$ -polarization and fraction of longitudinal polarization at LHCb and Belle, we have also investigated these observables within our model framework which are aligning well with the standard model expectations. We perform a comprehensive analysis of the form factors across the whole accessible kinematic range of $q^{2}$ . Our results are consistent and compatible with other theoretical approaches as well as with the experimental measurements. Furthermore, we evaluated the clean ratios of $B_{s}$ to $B_{0}$ in the semimuonic mode that are in accordance with the LHCb measurements, and support the validity of the SU(3) flavor symmetry. Although the concept of new physics is facing a significant challenge at the current TeV scale, semileptonic $B$ decays, nevertheless, always serve as a valuable probe to study the decay dynamics.

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https://github.com/Patnaik93-collab/semileptonicBdata.git

Phys. Rev. D 112, 033003– Published 13 August, 2025

Vol. 112, Iss. 3 — 1 August 2025

Received 19 May 2025
Accepted 10 July 2025

DOI: https://doi.org/10.1103/xtcf-2vw9

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

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$B \to D^{(*)} τ ν_{τ}$ decay properties with the relativistic independent quark model

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B→D(*)τντ decay properties with the relativistic independent quark model

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References (82)

$B \to D^{(*)} τ ν_{τ}$ decay properties with the relativistic independent quark model