arXiv subjects

N. R. Soni

Publications and source records attributed to N. R. Soni.

4 recordsLinked to original sources

arXiv2023

Prediction of various observables for $B_s^0 \to D_s^{(*)-}\ell^+ν_\ell$ within covariant confined quark model

In 2020, the LHCb collaboration reported the exclusive branching fractions for the channels $B_s^0 \to D_s^{(*)-}μ^+ν_μ$ for the very first time. In view of these observations, we have recently reported the form factors and branching fraction computations for these channels employing the covariant confined quark model. As different other channels corresponding to $b \to c \ell ν_\ell$ have provided the hint for New Physics, the analysis of observables such as forward-backward asymmetry, longitudinal and transverse polarizations across the lepton flavours can serve as one of the important probes for the search for possible New Physics. In present work, we compute these observables for all the lepton flavours and compare our predictions with the other theoretical approaches.

hep-ph↗

arXiv2018

$Q\bar Q$ ($Q\in \{b, c\}$) spectroscopy using Cornell potential

The mass spectra and decay properties of heavy quarkonia are computed in nonrelativistic quark-antiquark Cornell potential model. We have employed the numerical solution of Schrödinger equation to obtain their mass spectra using only four parameters namely quark mass ($m_c$, $m_b$) and confinement strength ($A_{c\bar c}$, $A_{b\bar b}$). The spin hyperfine, spin-orbit and tensor components of the one gluon exchange interaction are computed perturbatively to determine the mass spectra of excited $S$, $P$, $D$ and $F$ states. Digamma, digluon and dilepton decays of these mesons are computed using the model parameters and numerical wave functions. The predicted spectroscopy and decay properties for quarkonia are found to be consistent with available experimental observations and results from other theoretical models. We also compute mass spectra and life time of the $B_c$ meson without additional parameters. The computed electromagnetic transition widths of heavy quarkonia and $B_c$ mesons are in tune with available experimental data and other theoretical approaches.

hep-ph↗

arXiv2017

Decay ${\mathit{D} \to} {{\mathit K}^{(*)}}{{\mathit \ell}^{+}}{{\mathit ν}_{\mathit \ell}}$ in covariant quark model

We study the leptonic and semileptonic $D$-meson decays (${{\mathit D} \to} {{\mathit \ell}^{+}}{{\mathit ν}_{\mathit \ell}}$ and ${\mathit{D} \to} {{\mathit K}^{(*)}}{{\mathit \ell}^{+}}{{\mathit ν}_{\mathit \ell}}$) in the framework of covariant quark model with built-in infrared confinement. We compute the required form factors in the entire kinematical momentum transfer region. The calculated form factors are used to evaluate the branching fractions of these transitions. We determine the following ratios of the partial widths: $Γ({{\mathit D}^{0}} \rightarrow {{\mathit K}^{-}}{{\mathit e}^{+}}{{\mathit ν}_{e}})/Γ({{\mathit D}^{+}} \rightarrow {\overline{\mathit K}^{0}}{{\mathit e}^{+}}{{\mathit ν}_{e}}) = 1.02$, $Γ({{\mathit D}^{0}} \rightarrow {{\mathit K}^{-}}{{\mathit μ}^{+}}{{\mathit ν}_{μ}})/Γ({{\mathit D}^{+}} \rightarrow {\overline{\mathit K}^{0}}{{\mathit μ}^{+}}{{\mathit ν}_{μ}}) = 0.99$ and $Γ({{\mathit D}^{+}} \rightarrow {\overline{\mathit K}^{0}}{{\mathit μ}^{+}}{{\mathit ν}_{μ}}) / Γ({{\mathit D}^{+}} \rightarrow {\overline{\mathit K}^{0}}{{\mathit e}^{+}}{{\mathit ν}_{e}}) = 0.97$ which are in close resemblance with the iso-spin invariance and experimental results.

hep-ph↗

arXiv2015

Decay rates and electromagnetic transitions of heavy quarkonia

The electromagnetic radiative transition widths for heavy quarkonia, as well as digamma and digluon decay widths, are computed in the framework of the extended harmonic confinement model (ERHM) and Coulomb plus power potential (CPP$_ν$) with varying potential index $ν$. The outcome is compared with the values obtained from other theoretical models and experimental results. While the mass spectra, digamma and digluon widths from ERHM as well as CPP$_{ν=1}$ are in good agreement with experimental data, the electromagnetic transition widths span over a wide range for the potential models considered here making it difficult to prefer a particular model over the others because of the lack of experimental data for most transition widths.

hep-ph↗