Abstract
In this extended analysis using the ZEUS detector at HERA, the photoproduction of isolated photons together with a jet is measured for different ranges of the fractional photon energy, x meas γ , contributing to the photon-jet final state. Cross sections are evaluated in the photon transverse-energy and pseudorapidity ranges 6 < E γ T < 15 GeV and −0.7 < η γ < 0.9, and for jet transverse-energy and pseudorapidity ranges 4 < E jet T < 35 GeV and −1.5 < η jet < 1.8, for an integrated luminosity of 374 pb−1. The kinematic observables studied comprise the transverse energy and pseudorapidity of the photon and the jet, the azimuthal difference between them, the fraction of proton energy taking part in the interaction, and the difference between the pseudorapidities of the photon and the jet. Higher-order theoretical calculations are compared to the results.
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ArXiv ePrint: 1405.7127
Supported by the Italian National Institute for Nuclear Physics (INFN). (1, 2, 5, 23, 24, 26, 29, 30)
Supported by the German Federal Ministry for Education and Research (BMBF), under contract No. 05 H09PDF. (3)
Supported by HIR grant UM.C/625/1/HIR/149 and UMRG grants RU006-2013, RP012A-13AFR and RP012B-13AFR from Universiti Malaya, and ERGS grant ER004-2012A from the Ministry of Education, Malaysia. (6)
Supported by the National Science Centre under contract No. DEC-2012/06/M/ST2/00428. (7, 8)
Supported by the Science and Technology Facilities Council, U.K. (12, 22, 32)
Supported by the German Federal Ministry for Education and Research (BMBF), under contract No. 05h09GUF, and the SFB 676 of the Deutsche Forschungsgemeinschaft (DFG). (13)
Supported by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) and its grants for Scientific Research. (14, 19, 25, 28)
Supported by the Natural Sciences and Engineering Research Council of Canada (NSERC). (18, 31, 36)
Supported by RF Presidential grant N 3042.2014.2 for the Leading Scientific Schools and by the Russian Ministry of Education and Science through its grant for Scientific Research on High Energy Physics. (20)
Supported by the Israel Science Foundation. (27)
Also funded by Max Planck Institute for Physics, Munich, Germany. (R. Aggarwal, P. Kaur, I. Singh)
Partially supported by the Polish National Science Centre projects DEC-2011/01/B/ST2/03643 and DEC-2011/03/B/ST2/00220. (W. Slominski)
Also affiliated with University College London, U.K. (K. Mujkic)
Supported by the Alexander von Humboldt Foundation. (V. Myronenko, O. Turkot, K. Wichmann)
Alexander von Humboldt Professor. (B. Foster)
Supported by DESY, Germany. (V. Aushev, Y. Aushev, V. Bokhonov, N. Zhmak)
Member of National Technical University of Ukraine, Kyiv Polytechnic Institute, Kyiv, Ukraine. (Y. Aushev, A. Iudin, R. Shevchenko)
Member of National University of Kyiv - Mohyla Academy, Kyiv, Ukraine. (N. Kovalchuk, O. Shkola, A. Trofymov, N. Zakharchuk)
External Scientific Member. (H. Abramowicz)
Also supported by DESY. (M. Wing)
Member of Lódz University, Poland. (W. Perlanski)
Deceased (A.S. Proskuryakov).
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The ZEUS collaboration., Abramowicz, H., Abt, I. et al. Further studies of the photoproduction of isolated photons with a jet at HERA. J. High Energ. Phys. 2014, 23 (2014). https://doi.org/10.1007/JHEP08(2014)023
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DOI: https://doi.org/10.1007/JHEP08(2014)023