Inclusive-jet photoproduction at HERA and determination of α s
Nuclear Physics B 864:1 (2012) 1-37
Authors:
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 Bamberger, AN Barakbaev, G Barbagli, G Bari, F Barreiro, N Bartosik, D Bartsch, M Basile, O Behnke, J Behr, U Behrens, L Bellagamba, A Bertolin, S Bhadra, M Bindi, C Blohm, V Bokhonov, T Bołd, K Bondarenko, EG Boos, K Borras, D Boscherini, D Bot, I Brock, E Brownson, R Brugnera, N Brümmer, A Bruni, G Bruni, B Brzozowska, PJ Bussey, B Bylsma, A Caldwell, M Capua, R Carlin, CD Catterall, S Chekanov, J Chwastowski, J Ciborowski, R Ciesielski, L Cifarelli, F Cindolo, A Contin, AM Cooper-Sarkar, N Coppola, M Corradi, F Corriveau, M Costa, G D'Agostini, F Dal Corso, J del Peso, RK Dementiev, S De Pasquale, M Derrick, RCE Devenish, D Dobur, BA Dolgoshein, G Dolinska, AT Doyle, V Drugakov, LS Durkin, S Dusini, Y Eisenberg, PF Ermolov, A Eskreys, S Fang, S Fazio, J Ferrando, MI Ferrero, J Figiel, M Forrest, B Foster, G Gach, A Galas, E Gallo, A Garfagnini, A Geiser, I Gialas, A Gizhko, LK Gladilin, D Gladkov, C Glasman, O Gogota, YA Golubkov, P Göttlicher, I Grabowska-Bołd, J Grebenyuk, I Gregor
Abstract:
Inclusive-jet cross sections have been measured in the reaction ep→e+jet+X for photon virtuality Q 2<1 GeV 2 and γp centre-of-mass energies in the region 14217 GeV and -1< jet<2.5. In addition, measurements of double-differential inclusive-jet cross sections are presented as functions of ETjet in different regions of jet. Next-to-leading-order QCD calculations give a good description of the measurements, except for jets with low ETjet and high jet. 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 α s(M Z) were extracted from the measurements and the energy-scale dependence of the coupling was determined. The value of α s(M Z) extracted from the measurements based on the k T jet algorithm is αs(MZ)=0.1206-0.0022+0.0023(exp.)-0.0035+0.0042(th.); the results from the anti-k T and SIScone algorithms are compatible with this value and have a similar precision. © 2012 Elsevier B.V.
