Precision measurement of the $\Xi_{cc}^{++}$ mass

TL;DR

This paper reports the most precise measurement to date of the $ ext{Xi}_{cc}^{++}$ baryon's mass using LHCb data from 2016-2018, employing two decay modes in proton-proton collisions at 13 TeV.

Contribution

It provides a highly precise measurement of the $ ext{Xi}_{cc}^{++}$ mass, improving upon previous results with new data and analysis techniques.

Findings

Mass of $ ext{Xi}_{cc}^{++}$ measured as 3621.55 MeV/c^2

Measurement uncertainty reduced compared to previous results

First to use these decay modes for such precision

Abstract

A measurement of the $\Xi_{cc}^{++}$ mass is performed using data collected by the LHCb experiment between 2016 and 2018 in $pp$ collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.6 $\mathrm{fb}^{-1}$. The $\Xi_{cc}^{++}$ candidates are reconstructed via the decay modes $\Xi_{cc}^{++}\to\Lambda_c^+K^-\pi^+\pi^+$ and $\Xi_{cc}^{++}\to\Xi_c^+\pi^+$. The result, $3621.55 \pm 0.23{\rm\,(stat)\,} \pm 0.30 {\rm\,(syst)\,}{\rm MeV}/c^2$, is the most precise measurement of the $\Xi_{cc}^{++}$ mass to date.