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arXiv · hep-ex/0112030

High-mass dijet cross sections in photoproduction at HERA

ZEUS Collaboration
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Abstract

Dijet differential cross sections for the reaction e+p -> e+ + jet + jet + X in the photoproduction regime have been measured with the ZEUS detector at HERA using an integrated luminosity of 42.7 pb**{-1}. The cross sections are given for photon-proton centre-of-mass energies in the range 134< W <277 GeV. The differential cross sections as a function of the dijet mass, Mjj, and of the dijet angular variables have been measured for 47 < Mjj < 160 GeV and compared to next-to-leading-order QCD calculations. The dijet events in the region 75< Mjj < 100 GeV have been used to derive a 95% C.L. upper limit on the cross section for Z0 photoproduction of sigma(e+ p -> e+ Z0 X} < 5.9 pb. Upper limits on the photoproduction of new heavy resonances decaying into two jets are also presented for masses in the range between 60 GeV and 155 GeV.

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ZEUS Collaboration. 2001-12-21. High-mass dijet cross sections in photoproduction at HERA. https://doi.org/10.1016/s0370-2693(02)01327-8

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