Observation of a new Ξ b baryon

The observation of a new b baryon via its strong decay into Ξb-π + (plus charge conjugates) is reported. The measurement uses a data sample of pp collisions at √s=7TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3fb -1. The known Ξb- baryon is reconstru...

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Detalhes bibliográficos
Autores: Chatrchyan, S., Brochero Cifuentes, J. A., Cabrillo, I. J., Calderon, Alicia, Chuang, S. H., Duarte Campderros, J., Felcini, Marta, Fernández-García, Marcos, Gómez, Gervasio, González Sánchez, J., Jorda, C., Lobelle Pardo, P., López Virto, A., Marco, Jesús, Marco, Rafael, Martínez-Rivero, Celso, Matorras, Francisco, Muñoz Sánchez, F. J., Rodrigo Anoro, Teresa, Rodríguez Marrero, Ana Y., Ruiz Jimeno, Alberto, Scodellaro, Luca, Sobron Sañudo, M., Vila, Iván, Vilar Cortabitarte, R., CMS Collaboration
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/108963
Acesso em linha:http://hdl.handle.net/10261/108963
Access Level:acceso abierto
Palavra-chave:ddc:530
Descrição
Resumo:The observation of a new b baryon via its strong decay into Ξb-π + (plus charge conjugates) is reported. The measurement uses a data sample of pp collisions at √s=7TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3fb -1. The known Ξb- baryon is reconstructed via the decay chain Ξb-→J/ψΞ -→μ +μ -Λ0π -, with Λ0→pπ -. A peak is observed in the distribution of the difference between the mass of the Ξb-π + system and the sum of the masses of the Ξb- and π +, with a significance exceeding 5 standard deviations. The mass difference of the peak is 14.84±0.74(stat)±0.28(syst)MeV. The new state most likely corresponds to the JP=3/2 + companion of the Ξ b. © 2012 CERN.