Beam-energy dependence of correlations between mean transverse momentum and anisotropic flow of charged particles in Au+Au collisions at RHIC

Authors

• B. E. Aboona, Texas AandM University
• J. Adam, Czech Technical University in Prague
• G. Agakishiev, Joint Institute for Nuclear Research, Dubna
• I. Aggarwal, Panjab University
• M. M. Aggarwal, Panjab University
• Z. Ahammed, Variable Energy Cyclotron Centre
• A. Aitbayev, Joint Institute for Nuclear Research, Dubna
• I. Alekseev, Russian Research Centre Kurchatov Institute
• E. Alpatov, Moscow Engineering Physics Institute
• A. K. Alshammri, Kent State University
• A. Aparin, Joint Institute for Nuclear Research, Dubna
• S. Aslam, Fudan University
• J. Atchison, Abilene Christian University
• G. S. Averichev, Joint Institute for Nuclear Research, Dubna
• V. Bairathi, Universidad de Tarapaca
• X. Bao, Shandong University
• P. Barik, Indian Institute of Science Education and Research (IISER)
• K. Barish, University of California Riverside
• S. Behera, Indian Institute of Science Education and Research (IISER) Tirupati
• P. Bhagat, University of Jammu
• A. Bhasin, University of Jammu
• S. Bhatta, Stony Brook University
• I. G. Bordyuzhin, Russian Research Centre Kurchatov Institute
• J. D. Brandenburg, Ohio State University
• A. V. Brandin, Moscow Engineering Physics Institute
• C. Broodo, University of Houston
• X. Z. Cai, Chinese Academy of Sciences
• H. Caines, Yale University
• M. Calderón De La Barca Sánchez, University of California Davis
• D. Cebra, University of California Davis
• J. Ceska, Czech Technical University in Prague

Abstract

The correlation between the mean transverse momentum, [p _T], and the squared anisotropic flow, v_n², on an event-by-event basis has been suggested to be influenced by the initial conditions in heavy-ion collisions. We present measurements of the variances and covariance of [p _T] and v_n², along with their dimensionless ratio, for Au+Au collisions at various beam energies: s_NN = 14.6, 19.6, 27, 54.4, and 200 GeV. Our measurements reveal a distinct energy-dependent behavior in the variances and covariances. In addition, the dimensionless ratio displays a similar behavior across different beam energies. We compare our measurements with hydrodynamic models and similar measurements from Pb+Pb collisions at the Large Hadron Collider (LHC). These findings provide valuable insights into the beam energy dependence of the specific shear viscosity (η / s) and initial-state effects, allowing for differentiating between different initial-state models.

Document Type

Article

Publication Date

5-1-2026

Notes/Citation Information

Publisher Copyright: © 2026 The Authors.

Digital Object Identifier (DOI)

10.1016/j.physletb.2026.140378

Archival?

Archival

Repository Citation

Aboona, B. E.; Adam, J.; Agakishiev, G.; Aggarwal, I.; Aggarwal, M. M.; Ahammed, Z.; Aitbayev, A.; Alekseev, I.; Alpatov, E.; Alshammri, A. K.; Aparin, A.; Aslam, S.; Atchison, J.; Averichev, G. S.; Bairathi, V.; Bao, X.; Barik, P.; Barish, K.; Behera, S.; Bhagat, P.; Bhasin, A.; Bhatta, S.; Bordyuzhin, I. G.; Brandenburg, J. D.; Brandin, A. V.; Broodo, C.; Cai, X. Z.; Caines, H.; Sánchez, M. Calderón De La Barca; Cebra, D.; and Ceska, J., "Beam-energy dependence of correlations between mean transverse momentum and anisotropic flow of charged particles in Au+Au collisions at RHIC" (2026). Physics and Astronomy Faculty Publications. 777.
https://uknowledge.uky.edu/physastron_facpub/777