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{\large\bf Rapidity gaps between jets in photoproduction at HERA
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{H1 Collaboration}\\                            
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{\small \em DESY, Hamburg, Germany}\\[6mm]
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Photoproduction events which have two or more jets have been studied
in the $\gamma p$ centre-of-mass energy range $170$ GeV $ <  W <  243$ GeV
with the H1 detector at HERA. The fraction $f(\Delta \eta)$ of events with a
rapidity gap between the two highest $E_T$ jets is measured for $\Delta \eta >
3.5$ between the jet axes. An excess of events with a rapidity gap, over what
would be expected from standard photoproduction processes, is observed. The
excess can be interpreted as the result of the exchange of a strongly
interacting colour singlet object.

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