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arXiv · hep-ex/9509004

Hard Photoproduction by Colour Singlet Exchange at HERA

L. E. Sinclair
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Abstract

A search for photoproduction events which contain a rapidity gap between the two highest transverse energy jets has been conducted at HERA using the ZEUS detector. The jets have transverse energies greater than 6~GeV, and are separated by pseudorapidity intervals of up to four units. The fraction of events containing a gap is measured as a function of the gap-width. It is expected that this gap-fraction will fall exponentially with the gap-width, until the dominant gap-production mechanism becomes colour singlet exchange, at which point it will plateau. An indication of a plateau in the measured gap-fraction has been found, at a higher level than that expected from electroweak exchange.

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L. E. Sinclair. 1995-09-09. Hard Photoproduction by Colour Singlet Exchange at HERA. https://arxiv.org/abs/hep-ex/9509004

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