Excited doubly heavy baryon production via $W^+$ boson decays

TL;DR

This paper theoretically calculates the production rates and differential decay widths of doubly heavy baryons $\\Xi_{cc}$ and $\\\Xi_{bc}$ from $W^+$ boson decays using NRQCD, including S and P wave contributions, predicting high event numbers at the LHC.

Contribution

It provides the first comprehensive calculation of decay widths and differential distributions for doubly heavy baryons from $W^+$ decays, including P wave contributions and phase space analysis.

Findings

P wave contributions are about one order lower than S wave.

Estimated LHC events: 3.69×10^5 for $\Xi_{cc}$ and 4.91×10^4 for $\Xi_{bc}$ per year.

Differential decay widths are provided for various kinematic variables.

Abstract

In this paper, decay widths of the doubly heavy baryons ($\Xi_{cc} ~\text{and} ~\Xi_{bc}$) production are theoritically calculated in the whole phase space through $W^+ \to \Xi_{cc}+ \bar{c}+\bar{s}$ and $W^+ \to \Xi_{bc}+ \bar{b}+\bar{s}$, within the framework of nonrelativistic QCD (NRQCD). Differential widths $d\Gamma/ds_{12}$, $d\Gamma/ds_{23}$, $d\Gamma/dcos\theta_{12}$, and $d\Gamma/dcos\theta_{13}$ are also given. In addition to the ordinary S wave contributions for the baryons, we specifically calculate P wave contributions as a comparison, namely the high excited states of the intermediate diquark, including $[^1P_1]$ and $[^3P_J]$ (with $J=0,1,2$) in both color anti-triplet state $\overline{\mathbf{3}}$ and color sextuplet state $\mathbf{6}$. It shows that the contribution from P wave is about one order lower than S wave. According to the results, we can expect plentiful events produced at the LHC, i.e., $3.69\times10^5$ $\Xi_{cc}$ events and $4.91\times10^4$ $\Xi_{bc}$ events per year.