https://doi.org/10.1140/epjc/s10052-011-1578-5
Regular Article - Experimental Physics
Measurement of the cross section for diffractive deep-inelastic scattering with a leading proton at HERA
1
I. Physikalisches Institut der RWTH, Aachen, Germany
2
Vinca Institute of Nuclear Sciences, Belgrade, Serbia
3
School of Physics and Astronomy, University of Birmingham, Birmingham, UK
4
Inter-University Institute for High Energies ULB-VUB, Brussels and Universiteit Antwerpen, Antwerpen, Belgium
5
National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest, Romania
6
Rutherford Appleton Laboratory, Chilton, Didcot, UK
7
Institute for Nuclear Physics, Cracow, Poland
8
Institut für Physik, TU Dortmund, Dortmund, Germany
9
Joint Institute for Nuclear Research, Dubna, Russia
10
CEA, DSM/Irfu, CE-Saclay, Gif-sur-Yvette, France
11
DESY, Hamburg, Germany
12
Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany
13
Max-Planck-Institut für Kernphysik, Heidelberg, Germany
14
Physikalisches Institut, Universität Heidelberg, Heidelberg, Germany
15
Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany
16
Institute of Experimental Physics, Slovak Academy of Sciences, Košice, Slovak Republic
17
Department of Physics, University of Lancaster, Lancaster, UK
18
Department of Physics, University of Liverpool, Liverpool, UK
19
Queen Mary and Westfield College, London, UK
20
Physics Department, University of Lund, Lund, Sweden
21
CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille, France
22
Departamento de Fisica Aplicada, CINVESTAV, Mérida, Yucatán, Mexico
23
Departamento de Fisica, CINVESTAV IPN, México City, Mexico
24
Institute for Theoretical and Experimental Physics, Moscow, Russia
25
Lebedev Physical Institute, Moscow, Russia
26
Max-Planck-Institut für Physik, München, Germany
27
LAL, Université Paris-Sud, CNRS/IN2P3, Orsay, France
28
LLR, Ecole Polytechnique, CNRS/IN2P3, Palaiseau, France
29
LPNHE, Université Pierre et Marie Curie Paris 6, Université Denis Diderot Paris 7, CNRS/IN2P3, Paris, France
30
Faculty of Science, University of Montenegro, Podgorica, Montenegro
31
Institute of Physics, Academy of Sciences of the Czech Republic, Praha, Czech Republic
32
Faculty of Mathematics and Physics, Czech Republic, Charles University Praha,
33
Dipartimento di Fisica, Università di Roma Tre and INFN Roma 3, Rome, Italy
34
Institute for Nuclear Research and Nuclear Energy, Sofia, Bulgaria
35
Institute of Physics and Technology of the Mongolian Academy of Sciences, Ulaanbaatar, Mongolia
36
Paul Scherrer Institut, Villigen, Switzerland
37
Fachbereich C, Universität Wuppertal, Wuppertal, Germany
38
Yerevan Physics Institute, Yerevan, Armenia
39
DESY, Zeuthen, Germany
40
Institut für Teilchenphysik, ETH, Zürich, Switzerland
41
Physik-Institut der Universität Zürich, Zürich, Switzerland
* e-mail: kruegerk@mail.desy.de
Received:
8
October
2010
Revised:
17
January
2011
Published online:
2
March
2011
The cross section for the diffractive deep-inelastic scattering process ep→eXp is measured, with the leading final state proton detected in the H1 Forward Proton Spectrometer. The data sample covers the range x ℙ<0.1 in fractional proton longitudinal momentum loss, 0.1<|t|<0.7 GeV2 in squared four-momentum transfer at the proton vertex and 4<Q 2<700 GeV2 in photon virtuality. The cross section is measured four-fold differentially in t,x ℙ,Q 2 and β=x/x ℙ, where x is the Bjorken scaling variable. The t and x ℙ dependences are interpreted in terms of an effective pomeron trajectory and a sub-leading exchange. The data are compared with perturbative QCD predictions at next-to-leading order based on diffractive parton distribution functions previously extracted from complementary measurements of inclusive diffractive deep-inelastic scattering. The ratio of the diffractive to the inclusive ep cross section is studied as a function of Q 2,β and x ℙ.
© Springer-Verlag / Società Italiana di Fisica, 2011
