Measurement of exclusive Upsilon photoproduction from protons in pPb collisions at root sNN=5.02 Tev

• Main Authors: Sirunyan, A. M., Tumasyan, A. R., Adam, Wolfgang, Ambrogi, Federico, Asilar, Ece, Md. Ali, Mohd. Adli
• Format: Article
• Language: English; English; English
• Published: Springer New York LLC 2019
• Subjects: Q Science (General); QC Physics
• Online Access: http://irep.iium.edu.my/79910/1/79910_Measurement%20of%20exclusive%20%CF%92%20photoproduction_article.pdf; http://irep.iium.edu.my/79910/2/79910_Measurement%20of%20exclusive%20%CF%92%20photoproduction_scopus.pdf; http://irep.iium.edu.my/79910/3/79910_Measurement%20of%20exclusive%20%CF%92%20photoproduction_wos.pdf; http://irep.iium.edu.my/79910/; https://link.springer.com/content/pdf/10.1140/epjc/s10052-019-6774-8.pdf

The exclusive photoproduction of ϒ(nS) meson states from protons, γ p → ϒ(nS) p (with n = 1, 2, 3), is studied in ultraperipheral pPb collisions at a centre-of-mass energy per nucleon pair of √sNN = 5.02 TeV. The measurement is performed using the ϒ(nS) → μ+μ− decay mode, with data collected by the CMS experiment corresponding to an integrated luminosity of 32.6 nb−1. Differential cross sections as functions of the ϒ(nS) transverse momentum squared p2 T, and rapidity y, are presented. The ϒ(1S) photoproduction cross section is extracted in the rapidity range |y| < 2.2, which corresponds to photon–proton centre-ofmass energies in the range 91 < Wγ p < 826 GeV. The data are compared to theoretical predictions based on perturbative quantum chromodynamics and to previous measurements.