$^3_\Lambda\mathrm{H}$ and $^3_{\bar{\Lambda}}\mathrm{\bar{H}}$ lifetime measurement in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = $ 5.02 TeV via two-body decay

Abstract

An improved value for the lifetime of the (anti-)hypertriton has been obtained using the data sample of Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = $ 5.02 TeV collected by the ALICE experiment at the LHC. The (anti-)hypertriton has been reconstructed via its charged two-body mesonic decay channel and the lifetime has been determined from an exponential fit to the d$N$/d($ct$) spectrum. The measured value, $\tau$ = 242$^{+34}_{-38}$ (stat.) $\pm$ 17 (syst.) ps, is compatible with all the available theoretical predictions, thus contributing to the solution of the longstanding hypertriton lifetime puzzle.