$D_{sJ}(2860)$ From The Semileptonic Decays Of $B_s$ Mesons

TL;DR

This paper calculates decay form factors, rates, and branching ratios for semileptonic B_s decays into excited D-wave D_s mesons using heavy quark effective theory and QCD sum rules, providing predictions for experimental tests.

Contribution

It introduces a calculation of semileptonic decay form factors and decay widths for B_s mesons into excited D-wave D_s states using QCD sum rules within heavy quark effective theory, including newly observed states.

Findings

Decay widths are on the order of 10^{-19} to 10^{-16} GeV.

Branching ratios range from 10^{-7} to 10^{-4}.

Predictions include decay widths and branching ratios for B_s and B_s* semileptonic decays.

Abstract

In the framework of heavy quark effective theory, the leading order Isgur-Wise form factors relevant to semileptonic decays of the ground state $\bar{b}s$ meson $B_{s}$ into orbitally excited $D$-wave $\bar{c}s$ mesons, including the newly observed narrow $D^{*}_{s1}(2860)$ and $D^{*}_{s3}(2860)$ states by the LHCb Collaboration, are calculated with the QCD sum rule method. With these universal form factors, the decay rates and branching ratios are estimated. We find that the decay widths are $\Gamma(B_s\rightarrow D^{*}_{s1}\ell\bar{\nu}) =1.25^{+0.80}_{-0.60}\times10^{-19} \mbox{GeV}$, $\Gamma(B_s\rightarrow D^{'}_{s2}\ell\bar{\nu}) =1.49^{+0.97}_{-0.73}\times10^{-19} \mbox{GeV}$, $\Gamma(B_s\rightarrow D_{s2}\ell\bar{\nu}) =4.48^{+1.05}_{-0.94}\times10^{-17} \mbox{GeV}$, and $\Gamma(B_s\rightarrow D^{*}_{s3}\ell\bar{\nu}) = 1.52^{+0.35}_{-0.31}\times10^{-16} \mbox{GeV}$. The corresponding branching ratios are $\mathcal {B}(B_s\rightarrow D^{*}_{s1}\ell\bar{\nu}) =2.85^{+1.82}_{-1.36}\times 10^{-7}$, $\mathcal {B}(B_s\rightarrow D^{'}_{s2}\ell\bar{\nu}) =3.40^{+2.21}_{-1.66}\times 10^{-7}$, $\mathcal {B}(B_{s}\rightarrow D_{s2}\ell\bar{\nu}) =1.02^{+0.24}_{-0.21}\times 10^{-4}$, and $\mathcal {B}(B_s\rightarrow D^{*}_{s3}\ell\bar{\nu}) = 3.46^{+0.80}_{-0.70}\times 10^{-4}$. The decay widths and branching ratios of corresponding $B^{*}_{s}$ semileptonic processes are also predicted.