A search for the doubly-charmed-baryon decay Xicc++->Xic0pi+pi+ is performed using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 5.4 fb-1. A significant structure consistent with the Xicc++ baryon is observed in the Xic0pi+pi+ invariant-mass spectrum. Using the Xicc++ ->Lambdac+K-pi+pi+ decay as the normalisation channel, the branching fraction ratio, BR(Xicc++ -> Xic0pi+pi+)/BR(Xicc++→Lambdac+K-pi+pi+, is measured to be 1.37 \pm 0.18 (stat) \pm 0.09 (syst) \pm 0.35 (ext). This measurement provides critical input for testing QCD factorisation methods in the weak decays of doubly-heavy baryons, particularly in quantifying nonperturbative effects such as final-state interactions and resonance contributions to the hadronisation process.
Observation of the doubly-charmed-baryon decay Xicc++ -> Xic0pi+pi+
Kleijne N.Membro del Collaboration Group
;Morello M. J.Membro del Collaboration Group
;Passaro D.Membro del Collaboration Group
;Riccardi D.Membro del Collaboration Group
;
2025
Abstract
A search for the doubly-charmed-baryon decay Xicc++->Xic0pi+pi+ is performed using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 5.4 fb-1. A significant structure consistent with the Xicc++ baryon is observed in the Xic0pi+pi+ invariant-mass spectrum. Using the Xicc++ ->Lambdac+K-pi+pi+ decay as the normalisation channel, the branching fraction ratio, BR(Xicc++ -> Xic0pi+pi+)/BR(Xicc++→Lambdac+K-pi+pi+, is measured to be 1.37 \pm 0.18 (stat) \pm 0.09 (syst) \pm 0.35 (ext). This measurement provides critical input for testing QCD factorisation methods in the weak decays of doubly-heavy baryons, particularly in quantifying nonperturbative effects such as final-state interactions and resonance contributions to the hadronisation process.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.



