Evidence for X(3872) in Pb-Pb collisions and studies of its prompt production at √sNN = 5.02 TeV

The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of √sNN = 5.02 TeV per nucleon pair, using the decay chain X(3872) → J/ψπ+π -→ μ+μ-π+π-. The data were recorded wit...

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Detalles Bibliográficos
Autores: Sirunyan, Albert M., CMS Collaboration, Albajar Molera, Carmen, Fernández Trocóniz Acha, Jorge, Reyes Almanza, Rogelio
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/706566
Acceso en línea:http://hdl.handle.net/10486/706566
https://dx.doi.org/10.1103/PhysRevLett.128.032001
Access Level:acceso abierto
Palabra clave:CMS Detectors
Decay Chains
Pb-Pb Collisions
Heavy Ions
Física
Descripción
Sumario:The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of √sNN = 5.02 TeV per nucleon pair, using the decay chain X(3872) → J/ψπ+π -→ μ+μ-π+π-. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7 nb-1. The measurement is performed in the rapidity and transverse momentum ranges |y| <1.6 and 15 < pT< 50 GeV/c. The significance of the inclusive X(3872) signal is 4.2 standard deviations. The prompt X(3872) to ψ2S yield ratio is found to be ρPb-Pb = 1.08±0.49(stat) ± 0.52(syst), to be compared with typical values of 0.1 for pp collisions. This result provides a unique experimental input to theoretical models of the X(3872) production mechanism, and of the nature of this exotic state