Seminar in Hadronic Physics

Jet as a multi-scale probe for quark-gluon plasma

Yasuki Tachibana

Akita Intl. University

The jet is a multi-scale probe that can explore interactions in the quark-gluon plasma medium across a wide range of momentum scales. In the first part of the talk, we focus on the impact of scale-dependent jet-medium interactions on jet substructure observables, particularly during the high momentum and virtuality phase. Utilizing the JETSCAPE framework, we perform event-by-event Monte Carlo simulations with explicit virtuality dependence in the jet-medium interaction rate within the MATTER+LBT setup [1,2]. We emphasize jet substructure observables, such as Soft Drop groomed observables and the jet fragmentation function. Our results are compared to data and highlight the significant reduction in jet-medium interaction during the early high-virtuality stage.

Furthermore, we examine the medium's reaction to jet propagation, contrasting results from weakly coupled descriptions featuring recoiling partons with those from strongly coupled reports utilizing hydrodynamics [3]. Our findings reveal that the difference between the two prescriptions is most pronounced when the background medium flow is present. This study demonstrates that reconstructed jets have the potential to distinguish between different flow patterns of the underlying strongly interacting fluid.

[1] A. Kumar, Y. Tachibana, C. Sirimanna et al. (JETSCAPE) Inclusive Jet and Hadron Suppression in a Multi-Stage Approach, [arXiv:2204.01163 [hep-ph]].
[2] Y. Tachibana, A. Kumar, A. Majumder, et al. (JETSCAPE) Hard Jet Substructure in a Multi-stage Approach, [arXiv:2301.02485 [nucl-th]].
[3] Y. Tachibana, C. Shen, A. Majumder, Bulk medium evolution has considerable effects on jet observables, Phys. Rev. C 106, L021902 (2022) [arXiv:2001.08321 [nucl-th]].