Azimuthal correlations in photoproduction and deep inelastic ep scattering at HERA

Abt, I. et al. (2021) Azimuthal correlations in photoproduction and deep inelastic ep scattering at HERA. Journal of High Energy Physics, 2021(12), 102. (doi: 10.1007/JHEP12(2021)102)

Abstract

Collective behaviour of final-state hadrons, and multiparton interactions are studied in high-multiplicity ep scattering at a centre-of-mass energy s = 318 GeV with the ZEUS detector at HERA. Two- and four-particle azimuthal correlations, as well as multiplicity, transverse momentum, and pseudorapidity distributions for charged-particle multiplicities Nch ≥ 20 are measured. The dependence of two-particle correlations on the virtuality of the exchanged photon shows a clear transition from photoproduction to neutral current deep inelastic scattering. For the multiplicities studied, neither the measurements in photoproduction processes nor those in neutral current deep inelastic scattering indicate significant collective behaviour of the kind observed in high-multiplicity hadronic collisions at RHIC and the LHC. Comparisons of PYTHIA predictions with the measurements in photoproduction strongly indicate the presence of multiparton interactions from hadronic fluctuations of the exchanged photon.

• Item Type: Articles
• Keywords: Collective flow, lepton-nucleon scattering (experiments), particle correlations and fluctuations, quark gluon plasma.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Bussey, Dr Peter and Skillicorn, Professor Ian
• Authors: Abt, I., Aggarwal, R., Aushev, V., Behnke, O., Bertolin, A., Bloch, I., Brock, I., Brook, N. H., Brugnera, R., Bruni, A., Bussey, P. J., Caldwell, A., Catterall, C. D., Chwastowski, J., Ciborowski, J., Ciesielski, R., Cooper-Sarkar, A. M., Corradi, M., Dementiev, R. K., Dusini, S., Ferrando, J., Floerchinger, S., Foster, B., Gallo, E., Gangadharan, D., Garfagnini, A., Geiser, A., Gladilin, L. K., Golubkov, Y. A., Grzelak, G., Gwenlan, C., Hochman, D., Jomhari, N. Z., Kadenko, I., Karshon, U., Kaur, P., Klanner, R., Klein, U., Korzhavina, I. A., Kovalchuk, N., Kuze, M., Levchenko, B. B., Levy, A., Löhr, B., Lohrmann, E., Longhin, A., Lorkowski, F., Lukina, O. Y., Makarenko, I., Malka, J., Masciocchi, S., Nagano, K., Nam, J. D., Onderwaater, J., Onishchuk, Y., Paul, E., Pidhurskyi, I., Polini, A., Przybycień, M., Quintero, A., Ruspa, M., Schneekloth, U., Schörner-Sadenius, T., Selyuzhenkov, I., Shchedrolosiev, M., Shcheglova, L. M., Skillicorn, I. O., Słomiński, W., Solano, A., Stanco, L., Stefaniuk, N., Surrow, B., Tokushuku, K., Turkot, O., Tymieniecka, T., Verbytskyi, A., Wan Abdullah, W. A. T., Wichmann, K., Wing, M., Yamada, S., Yamazaki, Y., Żarnecki, A. F., and Zenaiev, O.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Journal of High Energy Physics
• Publisher: Springer
• ISSN: 1126-6708
• ISSN (Online): 1029-8479
• Published Online: 16 December 2021
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Journal of High Energy Physics 2021(12): 102
• Publisher Policy: Reproduced under a Creative Commons License