QM 2022

Search for collective effects in small systems obtained in ep collisions at HERA

7 Apr 2022, 16:50

20m

medium aula A (Auditorium Maximum UJ)

Oral presentation Hadron production and collective dynamics Parallel Session T14: Hadron production and collective dynamics

Speaker

Chuan Sun (Stony Brook University)

Description

Measurements of two- and multi-particle angular correlations are presented in both $ep$ deep-inelastic scattering at $\sqrt{s}=319$ GeV and in photoproduction off protons at energies $W_{\gamma p}=270$ GeV, as a function of charged-particle multiplicity. No long-range ridge structure is observed in the correlation functions. The second-order ($V_{2∆}$) and third-order ($V_{3∆}$) azimuthal anisotropy Fourier harmonics are extracted. Further, $C_2\{4\}$ signals are extracted from four-particle correlations for the first time in $ep$ collisions and are found to be positive or consistent with 0. In summary, collective behavior has not been observed in collisions of protons with virtual or quasi-real photons at HERA energies.

H1prelim-20-033

Presentation materials

20220407 - QM2022 - ChuanSun.pdf