Measurement of the exclusive Υ production cross-section in pp collisions at √{s}=7 TeV and 8 TeV

A study is presented of central exclusive production of Υ(nS) states, where the Υ(nS) resonances decay to the µ +µ − final state, using pp collision data recorded by the LHCb experiment. The cross-section is measured in the rapidity range 2 < y(Υ) < 4.5 where the muons are reconstructed in the...

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Detalles Bibliográficos
Autores: Badalov, Alexey, Casanova Mohr, Raimon, Garrido Beltrán, Lluís, Gascón Fora, David, Graciani Díaz, Ricardo, Graugés Pous, Eugeni, Mann Benito, Carla, Picatoste Olloqui, Eduardo, Rives Molina, Vicente José, Ruiz, Hugo (Ruiz Pérez), LHCb collaboration
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/185791
Acceso en línea:https://hdl.handle.net/2445/185791
Access Level:acceso abierto
Palabra clave:Hadrons
Gran Col·lisionador d'Hadrons
Física de partícules
Experiments
Large Hadron Collider (France and Switzerland)
Particle physics
Descripción
Sumario:A study is presented of central exclusive production of Υ(nS) states, where the Υ(nS) resonances decay to the µ +µ − final state, using pp collision data recorded by the LHCb experiment. The cross-section is measured in the rapidity range 2 < y(Υ) < 4.5 where the muons are reconstructed in the pseudorapidity range 2 < η(µ ±) < 4.5. The data sample corresponds to an integrated luminosity of 2.9 fb−1 and was collected at centre-of-mass energies of 7 TeV and 8 TeV. The measured Υ(1S) and Υ(2S) production cross-sections are σ(pp → pΥ(1S)p) = 9.0 ± 2.1 ± 1.7 pb and σ(pp → pΥ(2S)p) = 1.3 ± 0.8 ± 0.3 pb, where the first uncertainties are statistical and the second are systematic. The Υ(1S) cross-section is also measured as a function of rapidity and is found to be in good agreement with Standard Model predictions. An upper limit is set at 3.4 pb at the 95% confidence level for the exclusive Υ(3S) production cross-section, including possible contamination from χb(3P) → Υ(3S)γ decays.