Study of W boson production in PbPb and pp collisions at sNN=2.76 TeV

A measurement is presented of W-boson production in PbPb collisions carried out at a nucleon-nucleon (NN) centre-of-mass energy √ sNN of 2.76 TeV at the LHC using the CMS detector. In data corresponding to an integrated luminosity of 7.3 μb−1, the number of W → μνμ decays is extracted in the region...

Descripción completa

Detalles Bibliográficos
Autores: Chatrchyan, S., Brochero Cifuentes, Javier Andrés|||0000-0003-2093-7856, Cabrillo Bartolomé, José Iban|||0000-0002-0367-4022, Calderón Tazón, Alicia|||0000-0002-7205-2040, Chuang, S. H., Duarte Campderros, Jorge|||0000-0003-0687-5214, Felcini, Marta, Fernández García, Marcos|||0000-0002-4824-1087, Gómez Gramuglio, Gervasio|||0000-0002-1077-6553, González Sánchez, Francisco Javier, Jordá Lope, Clara, Lobelle Pardo, Patricia, López Virto, María Amparo, Marco de Lucas, Jesús|||0000-0001-7914-8494, Marco de Lucas, Rafael José, Martínez Rivero, Celso, Matorras Weinig, Francisco|||0000-0003-4295-5668, Muñoz Sánchez, Francisca Javiela, Rodrigo Anoro, Teresa, Rodríguez Marrero, Ana Yaiza, Ruiz Jimeno, Alberto|||0000-0002-3639-0368, Scodellaro, Luca|||0000-0002-4974-8330, Sobrón Sañudo, Mar, Vila Álvarez, Iván |||0000-0002-6797-7209, Vilar Cortabitarte, Rocío|||0000-0003-2045-8054
Tipo de recurso: artículo
Fecha de publicación:2012
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/26624
Acceso en línea:https://hdl.handle.net/10902/26624
Access Level:acceso abierto
Palabra clave:CMS
Physics
Heavy-ions
W bosons
Descripción
Sumario:A measurement is presented of W-boson production in PbPb collisions carried out at a nucleon-nucleon (NN) centre-of-mass energy √ sNN of 2.76 TeV at the LHC using the CMS detector. In data corresponding to an integrated luminosity of 7.3 μb−1, the number of W → μνμ decays is extracted in the region of muon pseudorapidity |ημ| < 2.1 and transverse momentum pμ T > 25 GeV/c. Yields of muons found per unit of pseudorapidity correspond to (159 ± 10(stat.) ± 12(syst.)) × 10−8 W+ and (154 ± 10(stat.) ± 12(syst.)) × 10−8 W−bosons per minimum-bias PbPb collision. The dependence of W production on the centrality of PbPb collisions is consistent with a scaling of the yield by the number of incoherent NN collisions. The yield of W bosons is also studied in a sample of pp interactions at s = 2.76 TeV corresponding to an integrated luminosity of 231 nb−1. The individual W+ and W- yields in PbPb and pp collisions are found to agree, once the neutron and proton content in Pb nuclei is taken into account. Likewise, the difference observed in the dependence of the positive and negative muon production on pseudorapidity is consistent with next-to-leading-order perturbative QCD calculations.