Eur. Phys. J. C (2007) 52: 813-832
https://doi.org/10.1140/epjc/s10052-007-0426-0

Regular Article - Experimental Physics

Dijet production in diffractive deep inelastic scattering at HERA

¹ Argonne National Laboratory, Argonne, Illinois, 60439-4815, USA
² Andrews University, Berrien Springs, Michigan, 49104-0380, USA
³ Institut für Physik, Humboldt-Universität zu Berlin, Berlin, Germany
⁴ University and INFN Bologna, Bologna, Italy
⁵ Physikalisches Institut, Universität Bonn, Bonn, Germany
⁶ H.H. Wills Physics Laboratory, University of Bristol, Bristol, UK
⁷ Physics Department and INFN, Calabria University, Cosenza, Italy
⁸ Chonnam National University, Kwangju, South Korea
⁹ Jabatan Fizik, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
¹⁰ Nevis Laboratories, Columbia University, Irvington on Hudson, New York, 10027, USA
¹¹ The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow, Poland
¹² Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Cracow, Poland
¹³ Department of Physics, Jagellonian University, Cracow, Poland
¹⁴ Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
¹⁵ Deutsches Elektronen-Synchrotron DESY, Zeuthen, Germany
¹⁶ University and INFN Florence, Florence, Italy
¹⁷ Fakultät für Physik, Universität Freiburg i.Br., Freiburg i.Br., Germany
¹⁸ Department of Physics and Astronomy, University of Glasgow, Glasgow, UK
¹⁹ Department of Engineering in Management and Finance, Univ. of Aegean, Mytilene, Greece
²⁰ Institute of Exp. Physics, Hamburg University, Hamburg, Germany
²¹ High Energy Nuclear Physics Group, Imperial College London, London, UK
²² Institute of Particle and Nuclear Studies, KEK, Tsukuba, Japan
²³ Institute of Physics and Technology, Ministry of Education and Science of Kazakhstan, Almaty, Kazakhstan
²⁴ Institute for Nuclear Research, National Academy of Sciences and Kiev National University, Kiev, Ukraine
²⁵ Kyungpook National University, Center for High Energy Physics, Daegu, South Korea
²⁶ Institut de Physique Nucléaire, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
²⁷ Departamento de Física Teórica, Universidad Autónoma de Madrid, Madrid, Spain
²⁸ Department of Physics, McGill University, Montréal, Québec, H3A 2T8, Canada
²⁹ Faculty of General Education, Meiji Gakuin University, Yokohama, Japan
³⁰ Moscow Engineering Physics Institute, Moscow, Russia
³¹ Institute of Nuclear Physics, Moscow State University, Moscow, Russia
³² Max-Planck-Institut für Physik, München, Germany
³³ NIKHEF and University of Amsterdam, Amsterdam, Netherlands
³⁴ Physics Department, Ohio State University, Columbus, Ohio, 43210, USA
³⁵ Department of Physics, University of Oxford, Oxford, UK
³⁶ Dipartimento di Fisica, Università and INFN, Padova, Italy
³⁷ Department of Physics, Pennsylvania State University, University Park, Pennsylvania, 16802, USA
³⁸ Polytechnic University, Sagamihara, Japan
³⁹ Dipartimento di Fisica, Università ’La Sapienza’ and INFN, Rome, Italy
⁴⁰ Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, UK
⁴¹ Raymond and Beverly Sackler Faculty of Exact Sciences, School of Physics, Tel-Aviv University, Tel-Aviv, Israel
⁴² Department of Physics, Tokyo Institute of Technology, Tokyo, Japan
⁴³ Department of Physics, University of Tokyo, Tokyo, Japan
⁴⁴ Department of Physics, Tokyo Metropolitan University, Tokyo, Japan
⁴⁵ Università di Torino and INFN, Torino, Italy
⁴⁶ Università del Piemonte Orientale, Novara, and INFN, Torino, Italy
⁴⁷ Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7, Canada
⁴⁸ Physics and Astronomy Department, University College London, London, UK
⁴⁹ Institute of Experimental Physics, Warsaw University, Warsaw, Poland
⁵⁰ Institute for Nuclear Studies, Warsaw, Poland
⁵¹ Department of Particle Physics, Weizmann Institute, Rehovot, Israel
⁵² Department of Physics, University of Wisconsin, Madison, Wisconsin, 53706, USA
⁵³ Department of Physics, York University, York, Ontario, M3J 1P3, Canada
⁵⁴ University College London, London, UK
⁵⁵ Humboldt University, Berlin, Germany
⁵⁶ Univ. Libre de Bruxelles, Bruxelles, Belgium
⁵⁷ DESY group FEB, Hamburg, Germany
⁵⁸ Stanford Linear Accelerator Center, Stanford, USA
⁵⁹ University of Liverpool, Liverpool, UK
⁶⁰ Institut of Theoretical and Experimental Physics, Moscow, Russia
⁶¹ INP, Cracow, Poland
⁶² DESY, Hamburg, Germany
⁶³ CERN, Geneva, Switzerland
⁶⁴ University of Tokyo, Tokyo, Japan
⁶⁵ Kobe University, Kobe, Japan
⁶⁶ Max Planck Institute, Munich, Germany
⁶⁷ KEK, Tsukuba, Japan
⁶⁸ Nagoya University, Nagoya, Japan
⁶⁹ Department of Radiological Science, University College London, London, UK
⁷⁰ Łódź University, Łódź, Poland

^* e-mail: gallo@mail.desy.de

Received: 13 August 2007
Published online: 9 October 2007

Abstract

The production of dijets in diffractive deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 61 pb^-1. The dijet cross section has been measured for virtualities of the exchanged virtual photon, 5 < Q² < 100 GeV², and γ^*p centre-of-mass energies, 100 < W < 250 GeV. The jets, identified using the inclusive k_T algorithm in the γ^*p frame, were required to have a transverse energy E^* _T,jet > 4 GeV and the jet with the highest transverse energy was required to have E^* _T,jet > 5 GeV. All jets were required to be in the pseudorapidity range -3.5<η^* _jet<0. The differential cross sections are compared to leading-order predictions and next-to-leading-order QCD calculations based on recent diffractive parton densities extracted from inclusive diffractive deep inelastic scattering data.