Diffractive dijet photoproduction in ep collisions at HERA

Summary, in English

Measurements are presented of single and double-differential dijet cross sections in diffractive photoproduction based on a data sample with an integrated luminosity of 47 pb(-1). The events are of the type ep -> eXY, where the hadronic system X contains at least two jets and is separated by a large rapidity gap from the system Y, which consists of a leading proton or low-mass proton excitation. The dijet cross sections are compared with QCD calculations at next-to-leading order and with a Monte Carlo model based on leading order matrix elements with parton showers. The measured cross sections are smaller than those obtained from the next-to-leading order calculations by a factor of about 0.6. This suppression factor has no significant dependence on the fraction x (gamma) of the photon four-momentum entering the hard subprocess. Ratios of the diffractive to the inclusive dijet cross sections are measured for the first time and are compared with Monte Carlo models.

• Author: F. D. Aaron; C. Alexa; V. Andreev; S. Backovic; A. Baghdasaryan; E. Barrelet; W. Bartel; K. Begzsuren; A. Belousov; J. C. Bizot; V. Boudry; I. Bozovic-Jelisavcic; J. Bracinik; G. Brandt; M. Brinkmann; V. Brisson; D. Bruncko; A. Bunyatyan; G. Buschhorn; L. Bystritskaya; A. J. Campbell; K. B. Cantun Avila; K. Cerny; V. Cerny; V. Chekelian; A. Cholewa; J. G. Contreras; J. A. Coughlan; J. Cvach; J. B. Dainton; K. Daum; M. Deak; B. Delcourt; J. Delvax; E. A. De Wolf; C. Diaconu; M. Dobre; V. Dodonov; A. Dossanov; A. Dubak; G. Eckerlin; V. Efremenko; S. Egli; A. Eliseev; E. Elsen; A. Falkiewicz; L. Favart; A. Fedotov; R. Felst; J. Feltesse; J. Ferencei; D. -J. Fischer; M. Fleischer; A. Fomenko; E. Gabathuler; J. Gayler; S. Ghazaryan; A. Glazov; L. Goerlich; N. Gogitidze; M. Gouzevitch; C. Grab; A. Grebenyuk; T. Greenshaw; B. R. Grell; G. Grindhammer; S. Habib; D. Haidt; C. Helebrant; R. C. W. Henderson; E. Hennekemper; H. Henschel; M. Herbst; G. Herrera; M. Hildebrandt; K. H. Hiller; D. Hoffmann; R. Horisberger; T. Hreus; F. Huber; M. Jacquet; X. Janssen; Leif Jönsson; A. W. Jung; H. Jung; M. Kapichine; J. Katzy; I. R. Kenyon; C. Kiesling; M. Klein; C. Kleinwort; T. Kluge; A. Knutsson; R. Kogler; P. Kostka; M. Kraemer; J. Kretzschmar; A. Kropivnitskaya; K. Krueger; K. Kutak; M. P. J. Landon; W. Lange; G. Lastovicka-Medin; P. Laycock; A. Lebedev; V. Lendermann; S. Levonian; K. Lipka; B. List; J. List; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A. Makankine; E. Malinovski; P. Marage; Ll. Marti; H. -U. Martyn; S. J. Maxfield; A. Mehta; A. B. Meyer; H. Meyer; J. Meyer; S. Mikocki; I. Milcewicz-Mika; F. Moreau; A. Morozov; J. V. Morris; M. U. Mozer; M. Mudrinic; K. Mueller; Th. Naumann; P. R. Newman; C. Niebuhr; A. Nikiforov; D. Nikitin; G. Nowak; K. Nowak; J. E. Olsson; Sakar Osman; D. Ozerov; P. Pahl; V. Palichik; I. Panagoulias; M. Pandurovic; Th. Papadopoulou; C. Pascaud; G. D. Patel; E. Perez; A. Petrukhin; I. Picuric; S. Piec; H. Pirumov; D. Pitzl; R. Placakyte; B. Pokorny; R. Polifka; B. Povh; V. Radescu; N. Raicevic; A. Raspiareza; T. Ravdandorj; P. Reimer; E. Rizvi; P. Robmann; R. Roosen; A. Rostovtsev; M. Rotaru; J. E. Ruiz Tabasco; S. Rusakov; D. Salek; D. P. C. Sankey; M. Sauter; E. Sauvan; S. Schmitt; L. Schoeffel; A. Schoening; H. -C. Schultz-Coulon; F. Sefkow; R. N. Shaw-West; L. N. Shtarkov; S. Shushkevich; T. Sloan; I. Smiljanic; Y. Soloviev; P. Sopicki; D. South; V. Spaskov; A. Specka; Z. Staykova; M. Steder; B. Stella; G. Stoicea; U. Straumann; D. Sunar; T. Sykora; G. Thompson; P. D. Thompson; T. Toll; T. H. Tran; D. Traynor; P. Truoel; I. Tsakov; B. Tseepeldorj; J. Turnau; K. Urban; A. Valkarova; C. Vallee; P. Van Mechelen; A. Vargas Trevino; Y. Vazdik; M. von den Driesch; D. Wegener; E. Wuensch; J. Zacek; J. Zalesak; Z. Zhang; A. Zhokin; H. Zohrabyan; F. Zomer
• Department/s: Particle and nuclear physics
• Publishing year: 2010
• Language: English
• Pages: 15-37
• Publication/Series: European Physical Journal C. Particles and Fields
• Volume: 70
• Issue: 1-2
• Links: http://dx.doi.org/10.1140/epjc/s10052-010-1448-6
• Document type: Journal article
• Publisher: Springer
• Topic: Subatomic Physics
• Status: Published
• ISBN/ISSN/Other: ISSN: 1434-6044