Observation of Associated Near-Side and Away-Side Long-Range Correlations in √sNN=5.02 TeV Proton-Lead Collisions with the ATLAS Detector

Aad, G. and Abajyan, T. and Abbott, B. and Abdallah, J. and Khalek, S. A. and Abdelalim, A. A. and Abdinov, O. and Aben, R. and Abi, B. and Abolins, M. and AbouZeid, O. S. and Abramowicz, H. and Abreu, H. and Acharya, B. S. and Adamczyk, L. and Adams, D. L. and Addy, T. N. and Adelman, J. and Adomeit, S. and Adragna, P. and Adye, T. and Aefsky, S. and Aguilar-Saavedra, J. A. and Agustoni, M. and Ahlen, S. P. and Ahles, F. and Ahmad, A. and Ahsan, M. and Aielli, G. and Akesson, T. P. A. and Krasznahorkay, Attila and Nagai, Yoshikazu and Pásztor, Gabriella and Tóth, József (2013) Observation of Associated Near-Side and Away-Side Long-Range Correlations in √sNN=5.02 TeV Proton-Lead Collisions with the ATLAS Detector. PHYSICAL REVIEW LETTERS, 110 (18). ISSN 0031-9007

Preview

Text 1212.5198v3.pdf Available under License Creative Commons Attribution. Download (467kB) | Preview

Abstract

Two-particle correlations in relative azimuthal angle (∆φ) and pseudorapidity (∆η) are measured in √sNN = 5.02 TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1 μb−1 of data as a function of transverse momentum (pT) and the transverse energy (ΣEPb T ) summed over 3.1 < η < 4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2 < |∆η| < 5) near-side (∆φ ∼ 0) correlation that grows rapidly with increasing ΣEPb T . A long-range away-side (∆φ ∼ π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣEPb T , is found to match the near-side correlation in magnitude, shape (in ∆η and ∆φ) and ΣEPb T dependence. The resultant ∆φ correlation is approximately symmetric about π/2, and is consistent with a dominant cos 2∆φ modulation for all ΣEPb T ranges and particle pT.

Actions (login required)

Edit Item