6533b835fe1ef96bd129fc12
RESEARCH PRODUCT
Precision Measurement of the Mass and Lifetime of the Xi(-)(b) Baryon
Carlos Sánchez MayordomoArantza Oyanguren CamposPablo Ruiz VallsFernando Martínez VidalLhcb Collaborationsubject
inclusive weak decays; discarding 1/N(C); quark-model; beaty; charm; ruleFísica nuclearLHCb - Abteilung HofmannQCParticle Physics - ExperimentSettore FIS/04 - Fisica Nucleare e SubnucleareHigh Energy Physics - Experimentdescription
We report on measurements of the mass and lifetime of the Ξ[- over b] baryon using about 1800 Ξ[- over b] decays reconstructed in a proton-proton collision data set corresponding to an integrated luminosity of 3.0 fb[superscript -1] collected by the LHCb experiment. The decays are reconstructed in the Ξ[- over b] → Ξ[0 over c]π[superscript -], Ξ[0 over c] → pK[superscript -]K[superscript -]π[superscript +] channel and the mass and lifetime are measured using the Λ[0 over b] → Λ[+ over c]π[superscript -] mode as a reference. We measure M(Ξ[- over b] - M(Λ[0 over b]) = 178.36 ± 0.46 ± 0.16 MeV/c[superscript 2], (τ[subscript Ξ[- over b]/τ[subscript Λ[0 over b]) = 1.089 ± 0.026 ± 0.011, where the uncertainties are statistical and systematic, respectively. These results lead to a factor of 2 better precision on the Ξ[- over b] mass and lifetime compared to previous best measurements, and are consistent with theoretical expectations.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-05-02 |