Photon diffractive dissociation, gamma p --> Xp, has been studied at HERA with the ZEUS detector using ep interactions where the virtuality Q^2 of the exchanged photon is smaller than 0.02 GeV^2. The squared four-momentum t exchanged at the proton vertex was determined in the range 0.073 < \t\ < 0.40 GeV^2 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 < M(x) < 32 GeV, the t distribution has an exponential shape, dN/d\t\ proportional to exp (-b\t\), with a slope parameter b = 6.8 +/- 0.9 (stat.)(-1.1)(+1.2) (syst.) GeV^(-2).
Measurement of the t distribution in diffractive photoproduction at HERA.
ANZIVINO, Giuseppina
1998
Abstract
Photon diffractive dissociation, gamma p --> Xp, has been studied at HERA with the ZEUS detector using ep interactions where the virtuality Q^2 of the exchanged photon is smaller than 0.02 GeV^2. The squared four-momentum t exchanged at the proton vertex was determined in the range 0.073 < \t\ < 0.40 GeV^2 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 < M(x) < 32 GeV, the t distribution has an exponential shape, dN/d\t\ proportional to exp (-b\t\), with a slope parameter b = 6.8 +/- 0.9 (stat.)(-1.1)(+1.2) (syst.) GeV^(-2).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.