Measurement of the cross section ratio σ(χc₂)/σ(χc₁) for prompt χc production with CMS experiment

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2012

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Akin, Ilina Vasileva

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The prompt production of χc quarkonia is studied in proton-proton collisions at 7 TeV, using data collected by CMS in 2011 corresponding to an integrated luminosity of 4.6 fb −1. The χc mesons are reconstructed through their radiative decays to J/ψ and photon with J/ψ → μ+μ− . The photons are reconstructed through their conversion in electron-positron pairs in the tracking detector which gives a mass resolution sufficient for resolving these states. The ratio of the prompt production ₁cross sections for the χc1 and χc2 states, σ(χc2)/σ(χc1), has been determined as a function of the J/ψ transverse momentum between 7 and 25 GeV/c.

Subject Keywords

Proton-proton interactions., Nuclear reactions., Colliders (Nuclear physics)., Quarkoniums., Quantum chromodynamics., Mesons, Positronium., Particles (Nuclear physics)., Particle accelerators.

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http://etd.lib.metu.edu.tr/upload/12614979/index.pdf
https://hdl.handle.net/11511/21766

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

I. V. Akin, “Measurement of the cross section ratio σ(χc₂)/σ(χc₁) for prompt χc production with CMS experiment,” Ph.D. - Doctoral Program, Middle East Technical University, 2012.