Observation of J/ψp Resonances Consistent with Pentaquark States in Λ0b→J/ψK−p Decays
Observations of exotic structures in the J/ψp channel, which we refer to as charmonium-pentaquark states, in Λ0b→J/ψK−p decays are presented. The data sample corresponds to an integrated luminosity of 3 fb−1 acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude analysis of th...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2015 |
| País: | España |
| Institución: | Universitat Ramon Llull (URL) |
| Repositorio: | DAU Arxiu Digital de la Universitat Ramon Llull |
| OAI Identifier: | oai:dau.url.edu:20.500.14342/3281 |
| Acceso en línea: | http://hdl.handle.net/20.500.14342/3281 https://doi.org/10.1103/PhysRevLett.115.072001 |
| Access Level: | acceso abierto |
| Palabra clave: | Gran col·lisionador d'hadrons (França i Suïssa) Partícules (Física nuclear) 53 |
| Sumario: | Observations of exotic structures in the J/ψp channel, which we refer to as charmonium-pentaquark states, in Λ0b→J/ψK−p decays are presented. The data sample corresponds to an integrated luminosity of 3 fb−1 acquired with the LHCb detector from 7 and 8 TeV pp collisions. An amplitude analysis of the three-body final state reproduces the two-body mass and angular distributions. To obtain a satisfactory fit of the structures seen in the J/ψp mass spectrum, it is necessary to include two Breit-Wigner amplitudes that each describe a resonant state. The significance of each of these resonances is more than 9 standard deviations. One has a mass of 4380±8±29 MeV and a width of 205±18±86 MeV, while the second is narrower, with a mass of 4449.8±1.7±2.5 MeV and a width of 39±5±19 MeV. The preferred JP assignments are of opposite parity, with one state having spin 3/2 and the other 5/2. |
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