Inclusive-jet photoproduction at HERA and determination of [formula omitted

H Abramowicz,A Eskreys,D Bot,V Aushev,L Wiggers,A Longhin,B Foster,A Keramidas,M Basile,V Trusov,K Olkiewicz,U Samson,Y Eisenberg,Y Iga,B Reisert,I Rubinsky,F Januschek,A Parenti,K Wrona,V Monaco,O Kononeko,S Limentani,I Gialas,O Gogota,J Grebenyuk,O Behnke,T Tsurugai,S De Pasquale,N Zhmak,V Drugakov,E Brownson,O Bachynska,W Słomiński,A Stifutkin,B Brzozowska,K Oliver,B Löhr,A Nigro,H Hartmann,U Karshon,S Bhadra,T Kanno,N Brümmer,B Pawlik,T Tymieniecka,R Walczak,J Sztuk-Dambietz,G Grzelak,D.S Zotkin,L Zawiejski,K Horton,H Wolfe,U Noor,G Bari,K Papageorgiu,D Szuba,F Mohamad Idris,G Marini,S Fazio,D Notz,D Gladkov,J Szuba,G Sartorelli,F Dal Corso,P Kaur,U Kötz,A.S Proskuryakov,A Kotański,M Derrick,K Mujkic,A Bruni,E Lohrmann,C Youngman,B.O Zhautykov,A Hüttmann,L Suszycki,M Wlasenko,B Musgrave,T Namsoo,A Garfagnini,T Theedt,S Schlenstedt,N Okazaki,R Brugnera,A Galas,I Abt,V Bokhonov,U Schneekloth,R Hamatsu,M Turcato,S Kananov,J Ciborowski,J Malka,S Magill,W Hain,C Blohm,S Dusini,E Hilger,Y Aushev,B.Y Oh,M Jüngst,M.C.K Mattingly,P Stopa,D Boscherini,J Del Peso,M Adamus,A Polini,S Antonelli,D Hochman,J Tomaszewska,G Grigorescu,A Bertolin,A Bamberger,Y.D Ri,F Karstens,A Raval,M Kuze,H Kowalski,V Schönberg,R Yoshida,D.D Reeder,Ie Korol,R Ingbir,L Bellagamba,R Hori,B Kahle,P Göttlicher,O Zabiegalov,I A Korzhavina ,J F Martin ,L A Khein ,E Gallo,R Nania,N Vlasov ,F Sciulli,A Lee,G Dolinska,V Libov,E Koffeman,A Margotti,А Спиридонов ,D Bartsch,R C E Devenish ,M Schioppa,M Forrest,L Adamczyk,Z Zolkapli,B Bylsma,S Yamada,I M Gregor ,G Hartner,A Tapper ,J Behr,L Cifarelli,R J Nowak ,Philipp Roloff ,Y Yamazaki,O Viazlo,A Gizhko,A Mastroberardino,J Terrón,M P Guzik ,P Bussey ,D Lontkovskyi,R K Dementiev ,N Kondrashova,J.Y Kim,N Stefaniuk,A Savin ,S Chekanov,A F Żarnecki ,J M Pawlak ,M Vázquez,K Nagano,I.-A Melzer-Pellmann,L.M Shcheglova,І Каденко ,W B Schmidke ,M Lisovyi,J Figiel,J Ferrando,Y Onishchuk ,N S Pokrovskiy ,A Verbytskyi,G Barbagli,B A Dolgoshein ,H Perrey,S Shimizu,R Shehzadi,Wolfram Dietrich Zeuner ,G D’agostini ,А Антонов ,A M Cooper-Sarkar ,A Stern,G Bruni,P Antonioli,N Bartosik,W Lohmann,A Zichichi,C Glasman,J J Whitmore ,M Corradi,R Mankel,C Zhou,K Long ,Wan Ahmad Tajuddin Wan Abdullah ,D Kisielewska,G Wolf,J J Chwastowski ,J C Hart ,A N Barakbaev ,N Coppola,Ning Ye ,R Klanner,R Sacchi,T Haas,I Grabowska-Bołd,M Wing,E Lobodzinska,L K Gladilin ,T Bołd,Z Ren,U Klein,R Aggarwal,M Przybycién ,T P Stewart ,Yu A Golubkov ,O Yu Lukina ,J Schwartz,R Ciesielski,S Kitamura,P Kooijman,A Montanari,Inderpal Singh ,I Katkov ,S Miglioranzi,S Mergelmeyer,S S Fang ,M Bindi,B B Levchenko ,D Dobur,V Sosnovtsev,O Turkot,L Stančo ,F Corriveau,P Pluciński,A Levy,G Susinno,J Repond,J Maeda,M I Ferrero ,M Kaur,D Son,A G Yagües-Molina ,T Schörner-Sadenius,P Ermolov ,A Pellegrino,T Nobe,M Capua,K Tokushuku,M Ishitsuka,O Kuprash,U Behrens,Lloyd Stanley Durkin ,S Suchkov,C D Catterall ,P G Pelfer ,J D Morris ,K Borras,P Schleper,H Stadie,O Zenaiev,Zainol Abidin Ibrahim ,A T Doyle ,D H Saxon ,O Gueta,I Brock,H.‐P Jakob ,R Carlin,A Caldwell,I O Skillicorn ,M Costa,W H Smith ,M Ruspa,K Piotrzkowski,C Gwenlan,A Geiser,I Makarenko,A E Nuncio-Quiroz ,G P Gach ,E.G Boos,A I Robertson ,A Solano,F Barreiro,V Sola,T W Jones ,A Contin,T Y Ling ,M Arneodo,E Paul,E Tassi,F Cindolo,H Tiecke,Kyrylo Bondarenko ,W Perlański

doi:10.1016/j.nuclphysb.2012.06.006

Abstract

Inclusive-jet cross sections have been measured in the reaction ep→e+jet+X for photon virtuality Q2<1 GeV2 and γp centre-of-mass energies in the region 142<Wγp<293 GeV with the ZEUS detector at HERA using an integrated luminosity of 300 pb−1. Jets were identified using the kT, anti-kT or SIScone jet algorithms in the laboratory frame. Single-differential cross sections are presented as functions of the jet transverse energy, ETjet, and pseudorapidity, ηjet, for jets with ETjet>17 GeV and −1<ηjet<2.5. In addition, measurements of double-differential inclusive-jet cross sections are presented as functions of ETjet in different regions of ηjet. Next-to-leading-order QCD calculations give a good description of the measurements, except for jets with low ETjet and high ηjet. The influence of non-perturbative effects not related to hadronisation was studied. Measurements of the ratios of cross sections using different jet algorithms are also presented; the measured ratios are well described by calculations including up to O(αs2) terms. Values of αs(MZ) were extracted from the measurements and the energy-scale dependence of the coupling was determined. The value of αs(MZ) extracted from the measurements based on the kT jet algorithm is αs(MZ)=0.1206−0.0022+0.0023(exp.)−0.0035+0.0042(th.); the results from the anti-kT and SIScone algorithms are compatible with this value and have a similar precision.

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