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Measurement of Dijet Production at Low Q^2 at HERA

H1 Collaboration
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Abstract

Triple differential dijet cross sections in e^\pm p interactions are presented in the region of photon virtualities 2 7GeV, E_T2>5GeV, and pseudorapidities -2.5 < eta_1^*, eta_2^* <0. The measurements are made in the gamma^* p centre-of-mass frame, using an integrated luminosity of 57pb^-1. The data are compared with NLO QCD calculations and LO Monte Carlo programs with and without a resolved virtual photon contribution. NLO QCD calculations fail to describe the region of low Q^2 and low jet transverse energies, in contrast to a LO Monte Carlo generator which includes direct and resolved photon interactions with both transversely and longitudinally polarised photons. Initial and final state parton showers are tested as a mechanism for including higher order QCD effects in low E_T jet production.

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H1 Collaboration. 2004-01-12. Measurement of Dijet Production at Low Q^2 at HERA. https://doi.org/10.1140/epjc%2Fs2004-01957-3

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