Observation of the B+c meson in Pb-Pb and pp collisions at √sNN = 5.02  TeV and measurement of its nuclear modification factor

• Autor(a) principal: Tumasyan, Armen
• Data de Publicação: 2022
• Outros Autores: Silveira, Gustavo Gil da, Bernardes, César Augusto, CMS Collaboration
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/249590
• topic: Aceleradores de partículas; Colisões proton-proton; Colisao de ions pesados; Mesons

The B+c meson is observed for the first time in heavy ion collisions. Data from the CMS detector are used to study the production of the B+c meson in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a center of-mass energy per nucleon pair of √sNN = 5.02 TeV, via the B+c → (J/ψ→μ+μ−)μ+νμ decay. The B+c nuclear modification factor, derived from the Pb-Pb–to–pp ratio of production cross sections, is measured in two bins of the trimuon transverse momentum and of the Pb-Pb collision centrality. The B+c meson is shown to be less suppressed than quarkonia and most of the open heavy-flavor mesons, suggesting that effects of the hot and dense nuclear matter created in heavy ion collisions contribute to its production. This measurement sets forth a promising new probe of the interplay of suppression and enhancement mechanisms in the production of heavy-flavor mesons in the quark-gluon plasma.