Measurements of the charm jet cross section and nuclear modification factor in pPb collisions at sNN=5.02 TeV

• Main Authors: Sirunyan, A. M., Tumasyan, A. R., Adam, Wolfgang, Asilar, Ece, Bergauer, Thomas, Md. Ali, Mohd. Adli
• Format: Article
• Language: English; English
• Published: Elsevier BV 2017
• Subjects: Q Science (General); QC Physics
• Online Access: http://irep.iium.edu.my/63041/1/63041_Measurements%20of%20the%20charm%20jet%20cross%20section_article.pdf; http://irep.iium.edu.my/63041/2/63041_Measurements%20of%20the%20charm%20jet%20cross%20section_scopus.pdf; http://irep.iium.edu.my/63041/; https://ac.els-cdn.com/S0370269317305294/1-s2.0-S0370269317305294-main.pdf?_tid=f963c02c-8822-4d8d-b79b-aaaea1b3d670&acdnat=1521951723_4d67c1903ff9672b5e400eabefeacf1c

The CMS Collaboration presents the first measurement of the differential cross section of jets from charm quarks produced in proton–lead (pPb) collisions at a nucleon–nucleon center-of-mass energy of √sNN = 5.02 TeV, as well as results from charm quark jets in proton–proton (pp) collisions at √s = 2.76 and 5.02 TeV. By comparing the yields of the pPb and pp collision systems at the same energy, a nuclear modification factor for charm jets from 55 to 400 GeV/c in pPb collisions at √sNN = 5.02 TeV of RpA = 0.92 ± 0.07 (stat)± 0.11 (syst) is obtained. This is consistent with an absence of final-state energy loss for charm quarks in pPb collisions. In addition, the fraction of jets coming from charm quarks is found to be consistent with that predicted by pythia 6 for pp collisions at √s = 2.76 and 5.02 TeV, and is independent of the jet transverse momentum from 55 to 400 GeV/c.