Differential cross sections for jet photoproduction in the reaction ep --> e jet X have been measured with the ZEUS detector at HERA using 82.2 pb(-1) of integrated luminosity. Inclusive jet cross sections are presented as a function of the jet transverse energy, E-T(jet), for jets with E-T(jet) > 17 GeV and pseudorapidity -1 < eta(jet) < 2.5, in the gammap centre-of-mass-energy range 142 < Wgammap < 293 GeV. Scaled jet invariant cross sections are presented as a function of the dimensionless variable x(T) equivalent to 2E(T)(jet)/W-gammap for (W-gammap) = 180 and 255 GeV: Next-to-leading-order QCD calculations give a good description of the measured differential cross sections in both magnitude and shape. The ratio of scaled jet invariant cross sections at the two (Wgammap) values shows clear non-scaling behaviour. A value for the strong coupling constant of alpha(s) (M-Z) = 0.1224 +/- 0.0001(stat.)(-0.0019)(+0.0022)(exp.)(-0.0042)(+0.0054)(th.) has been extracted from a QCD analysis of the measured dsigma/dE(T)(jet). The variation of sigma(s) with E-T(jet) is in good agreement with the running of sigma(s) as predicted by QCD. (C) 2003 Published by Elsevier Science B.V. RI De Pasquale, Salvatore/B-9165-2008; Wing, Matthew/C-2169-2008; Doyle, Anthony/C-5889-2009; collins-tooth, christopher/A-9201-2012; Ferrando, James/A-9192-2012; Gladilin, Leonid/B-5226-2011; Golubkov, Yury/E-1643-2012

Differential cross sections for jet photoproduction in the reaction ep --> e jet X have been measured with the ZEUS detector at HERA using 82.2 pb(-1) of integrated luminosity. Inclusive jet cross sections are presented as a function of the jet transverse energy, E(T)(jet), for jets with E(T)(jet) > 17 GeV and pseudorapidity -1 < eta(jet) < 2.5, in the gammap centre-of-mass-energy range 142 < Wgammap < 293 GeV. Scaled jet invariant cross sections are presented as a function of the dimensionless variable x(T) equivalent to 2E(T)(jet)/W(gammap) for (W(gammap)) = 180 and 255 GeV: Next-to-leading-order QCD calculations give a good description of the measured differential cross sections in both magnitude and shape. The ratio of scaled jet invariant cross sections at the two (Wgammap) values shows clear non-scaling behaviour. A value for the strong coupling constant of alpha(s) (M(Z)) = 0.1224 +/- 0.0001(stat.)(-0.0019)(+0.0022)(exp.)(-0.0042)(+0.0054)(th.) has been extracted from a QCD analysis of the measured dsigma/dE(T)(jet). The variation of sigma(s) with E(T)(jet) is in good agreement with the running of sigma(s) as predicted by QCD. (C) 2003 Published by Elsevier Science B.V.

Scaling violations and determination of alpha(s) from jet production in gamma p interactions at HERA

Chekanov S;Capua M;SCHIOPPA, Marco;Tassi E;
2003-01-01

Abstract

Differential cross sections for jet photoproduction in the reaction ep --> e jet X have been measured with the ZEUS detector at HERA using 82.2 pb(-1) of integrated luminosity. Inclusive jet cross sections are presented as a function of the jet transverse energy, E-T(jet), for jets with E-T(jet) > 17 GeV and pseudorapidity -1 < eta(jet) < 2.5, in the gammap centre-of-mass-energy range 142 < Wgammap < 293 GeV. Scaled jet invariant cross sections are presented as a function of the dimensionless variable x(T) equivalent to 2E(T)(jet)/W-gammap for (W-gammap) = 180 and 255 GeV: Next-to-leading-order QCD calculations give a good description of the measured differential cross sections in both magnitude and shape. The ratio of scaled jet invariant cross sections at the two (Wgammap) values shows clear non-scaling behaviour. A value for the strong coupling constant of alpha(s) (M-Z) = 0.1224 +/- 0.0001(stat.)(-0.0019)(+0.0022)(exp.)(-0.0042)(+0.0054)(th.) has been extracted from a QCD analysis of the measured dsigma/dE(T)(jet). The variation of sigma(s) with E-T(jet) is in good agreement with the running of sigma(s) as predicted by QCD. (C) 2003 Published by Elsevier Science B.V. RI De Pasquale, Salvatore/B-9165-2008; Wing, Matthew/C-2169-2008; Doyle, Anthony/C-5889-2009; collins-tooth, christopher/A-9201-2012; Ferrando, James/A-9192-2012; Gladilin, Leonid/B-5226-2011; Golubkov, Yury/E-1643-2012
Differential cross sections for jet photoproduction in the reaction ep --> e jet X have been measured with the ZEUS detector at HERA using 82.2 pb(-1) of integrated luminosity. Inclusive jet cross sections are presented as a function of the jet transverse energy, E(T)(jet), for jets with E(T)(jet) > 17 GeV and pseudorapidity -1 < eta(jet) < 2.5, in the gammap centre-of-mass-energy range 142 < Wgammap < 293 GeV. Scaled jet invariant cross sections are presented as a function of the dimensionless variable x(T) equivalent to 2E(T)(jet)/W(gammap) for (W(gammap)) = 180 and 255 GeV: Next-to-leading-order QCD calculations give a good description of the measured differential cross sections in both magnitude and shape. The ratio of scaled jet invariant cross sections at the two (Wgammap) values shows clear non-scaling behaviour. A value for the strong coupling constant of alpha(s) (M(Z)) = 0.1224 +/- 0.0001(stat.)(-0.0019)(+0.0022)(exp.)(-0.0042)(+0.0054)(th.) has been extracted from a QCD analysis of the measured dsigma/dE(T)(jet). The variation of sigma(s) with E(T)(jet) is in good agreement with the running of sigma(s) as predicted by QCD. (C) 2003 Published by Elsevier Science B.V.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11770/127675
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 41
  • ???jsp.display-item.citation.isi??? 42
social impact