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arXiv · hep-ex/0612008

Photoproduction of events with rapidity gaps between jets at HERA

ZEUS Collaboration·S. Chekanov
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Abstract

The photoproduction of dijet events, where the two jets with the highest transverse energy are separated by a large gap in pseudorapidity, have been studied with the ZEUS detector using an integrated luminosity of 39 pb$^{-1}$. Rapidity-gap events are defined in terms of the energy flow between the jets, such that the total summed transverse energy in this region is less than some value $E_{\rm T}^{\rm CUT}$. The data show a clear excess over the predictions of standard photoproduction models. This is interpreted as evidence for a strongly interacting exchange of a color-singlet object. Monte Carlo models which include such a color-singlet exchange are able to describe the data.

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ZEUS Collaboration, S. Chekanov. 2007-01-31. Photoproduction of events with rapidity gaps between jets at HERA. https://doi.org/10.1140/epjc%2Fs10052-007-0241-7

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