Measurement of jet-medium interactions via direct photon-hadron correlations in Au+Au and d+Au collisions at sNN =200 GeV

Summary, in English

We present direct photon-hadron correlations in 200 GeV/A Au+Au, d+Au, and p+p collisions, for direct photon pT from 5-12 GeV/c, collected by the PHENIX Collaboration in the years from 2006 to 2011. We observe no significant modification of jet fragmentation in d+Au collisions, indicating that cold nuclear matter effects are small or absent. Hadrons carrying a large fraction of the quark's momentum are suppressed in Au+Au compared to p+p and d+Au. As the momentum fraction decreases, the yield of hadrons in Au+Au increases to an excess over the yield in p+p collisions. The excess is at large angles and at low hadron pT and is most pronounced for hadrons associated with lower momentum direct photons. Comparison to theoretical calculations suggests that the hadron excess arises from medium response to energy deposited by jets. © 2020 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.

• Author: U. Acharya; Peter Christiansen; Hans-Åke Gustafsson; Eva Haslum; Anders Oskarsson; Sarah Rosendahl; David Silvermyr; Evert Stenlund; L. Zou
• Department/s: eSSENCE: The e-Science Collaboration; Particle and nuclear physics
• Publishing year: 2020
• Language: English
• Publication/Series: Physical Review C
• Volume: 102
• Issue: 5
• Links: http://dx.doi.org/10.1103/PhysRevC.102.054910
• Document type: Journal article
• Publisher: American Physical Society
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 2469-9985