The exclusive photoproduction reaction gamma p -> gamma(1S)p has been studied with the ZEUS detector in ep collisions at HERA using an integrated luminosity of 468 pb(-1). The measurement covers the kinematic range 60 < W < 220 GeV and Q(2) < 1 GeV2, where W is the photon-proton centre-of-mass energy and Q(2) is the photon virtuality. The exponential slope, b, of the t dependence of the cross section, where t is the squared four-momentum transfer at the proton vertex, has been measured, yielding b = 4.3(-1.3)(+2.0)(stat.)(-0.6)(+0.5) (syst.) GeV-2. This constitutes the first measurement of the t dependence of the gamma p -> gamma(1S)p cross section. (C) 2012 Elsevier B.V. All rights reserved.

Measurement of the t dependence in exclusive photoproduction of gamma(1s) mesons at HERA

COSTA, Marco;MONACO, Vincenzo;SACCHI, Roberto;V. Sola;SOLANO, Ada Maria;
2012-01-01

Abstract

The exclusive photoproduction reaction gamma p -> gamma(1S)p has been studied with the ZEUS detector in ep collisions at HERA using an integrated luminosity of 468 pb(-1). The measurement covers the kinematic range 60 < W < 220 GeV and Q(2) < 1 GeV2, where W is the photon-proton centre-of-mass energy and Q(2) is the photon virtuality. The exponential slope, b, of the t dependence of the cross section, where t is the squared four-momentum transfer at the proton vertex, has been measured, yielding b = 4.3(-1.3)(+2.0)(stat.)(-0.6)(+0.5) (syst.) GeV-2. This constitutes the first measurement of the t dependence of the gamma p -> gamma(1S)p cross section. (C) 2012 Elsevier B.V. All rights reserved.
2012
708
14
20
http://dx.doi.org/10.1016/j.physletb.2012.01.009
ZEUS; CENTRAL TRACKING DETECTOR; VIRTUAL COMPTON-SCATTERING; ZEUS BARREL CALORIMETER; J/PSI MESONS; UPSILON PHOTOPRODUCTION; VECTOR-MESONS; ELECTROPRODUCTION; DESIGN; CONSTRUCTION; SYSTEM
H. Abramowicz;I. Abt;L. Adamczyk;M. Adamus;R. Aggarwal;S. Antonelli;P. Antonioli;A. Antonov;M. Arneodo;V. Aushev;Y. Aushev;O. Bachynska;A....espandi
File in questo prodotto:
File Dimensione Formato  
820490.pdf

Accesso aperto

Tipo di file: PDF EDITORIALE
Dimensione 439.13 kB
Formato Adobe PDF
439.13 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/105553
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 21
  • ???jsp.display-item.citation.isi??? 16
social impact