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Study of the effective transverse momentum of partons in the proton using prompt photons in photoproduction at HERA

ZEUS Collaboration
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Abstract

The photoproduction of prompt photons, together with an accompanying jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb^{-1}. A study of the effective transverse momentum, k_T, of partons in the proton, as modelled within the framework of the PYTHIA Monte Carlo, gives a value of k_T = 1.69+/-0.18 ^{+0.18}_{-0.20} GeV for the photon-proton centre-of-mass energy range 134 < W < 251 GeV. This result is in agreement with the previously observed trend in hadron-hadron scattering for k_T to rise with interaction energy.

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ZEUS Collaboration. 2001-05-11. Study of the effective transverse momentum of partons in the proton using prompt photons in photoproduction at HERA. https://doi.org/10.1016/s0370-2693(01)00615-3

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