Observation of charge-dependent azimuthal correlations in p-Pb collisions and its implication for the search for the chiral magnetic effect

• Main Authors: Khachatryan, Vardan, Sirunyan, A. M., Tumasyan, A. R., Adam, Wolfgang, Asilar, Ece, Bergauer, Thomas, Md. Ali, Mohd. Adli
• Format: Article
• Language: English; English
• Published: American Physical Society 2017
• Subjects: Q Science (General); QC Physics
• Online Access: http://irep.iium.edu.my/63044/1/63044_Observation%20of%20Charge-Dependent%20Azimutha_article.pdf; http://irep.iium.edu.my/63044/2/63044_Observation%20of%20Charge-Dependent%20Azimutha_scopus.pdf; http://irep.iium.edu.my/63044/; https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.118.122301

Charge-dependent azimuthal particle correlations with respect to the second-order event plane in p-Pb and PbPb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV have been studied with the CMS experiment at the LHC. The measurement is performed with a three-particle correlation technique, using two particles with the same or opposite charge within the pseudorapidity range jηj < 2.4, and a third particle measured in the hadron forward calorimeters (4.4 < jηj < 5). The observed differences between the same and opposite sign correlations, as functions of multiplicity and η gap between the two charged particles, are of similar magnitude in p-Pb and PbPb collisions at the same multiplicities. These results pose a challenge for the interpretation of charge-dependent azimuthal correlations in heavy ion collisions in terms of the chiral magnetic effect.