28 July 2020 to 6 August 2020
virtual conference
Europe/Prague timezone

Two-particle azimuthal correlations as a probe of collective behaviour in deep inelastic ep scattering at HERA

31 Jul 2020, 09:36
24m
virtual conference

virtual conference

Talk 07. Heavy Ions Heavy Ions

Speaker

Achim Geiser (Deutsches Elektronen-Synchrotron (DE))

Description

Two-particle azimuthal correlations have been measured in neutral current deep inelastic $ep$ scattering with virtuality $Q^2 > 5$ GeV$^2$ at a centre-of-mass energy $\sqrt{s}=318$ GeV recorded with the ZEUS detector at HERA. The correlations of charged particles have been measured in the range of laboratory pseudorapidity $-1.5 < \eta < 2$ and transverse momentum $0.1 < p_T < 5$ GeV and event multiplicities $N_{ch}$ up to six times larger than the average $\langle N_{ch} \rangle \approx 5$. The two-particle correlations have been measured in terms of the angular observables $c_n\{2\}=\langle\langle\cos n\Delta\phi\rangle\rangle$, where $n$ is between 1 and 4 and $\Delta\phi$ is the relative azimuthal angle between the two particles. The correlations observed in HERA data do not indicate the kind of collective behaviour recently observed at the highest RHIC and LHC energies in high-multiplicity hadronic collisions. Available Monte Carlo models of deep inelastic scattering, tuned to reproduce inclusive particle production, provide a qualitative description of the HERA data.

Secondary track (number) 07

Primary authors

Matthew Wing (University College London) Achim Geiser (Deutsches Elektronen-Synchrotron (DE))

Presentation materials