Measurement of the t distribution
in
diffractive photoproduction at HERA
The ZEUS Collaboration, J. Breitweg et al.
Argonne National Laboratory, Argonne, IL, USA
Received: 3 December 1997
Abstract
Photon diffractive dissociation, 
, has been
studied at HERA with the ZEUS detector using ep interactions where the
virtuality Q2 of the exchanged photon is smaller than 0.02 GeV2.
The squared four-momentum t exchanged at the proton vertex was
determined in the range 0.073<|t|<0.40 GeV2 by measuring the
scattered proton in the ZEUS Leading Proton Spectrometer.
In the photon-proton centre-of-mass energy interval
176<W<225 GeV and for masses of the dissociated photon system 4<MX<32 GeV,
the t distribution has an exponential shape,
, with a slope
parameter 
(stat.) +1.2-1.1 (syst.) GeV-2.
Copyright Springer-Verlag
