Energy dependence of the differences between the quark and gluon jet fragmentation

Three jet events arising from decays of the Z boson, collected by the DELPHI detector, were used to measure differences in quark and gluon fragmentation. Gluon jets were anti-tagged by identifying b quark jets. Unbiased quark jets came from events with two jets plus one photon. Quark and gluon jet p...

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Main Authors: Abreu, P, Adam, W, Adye, T, Agasi, E, Ajinenko, I, Aleksan, R, Alekseev, G, Alemany, R, Allport, P, Almehed, S, Alvsvaag, S, Amaldi, U, Amato, S, Andreazza, A, Andrieux, M, Antilogus, P, Apel, W, Arnoud, Y, Asman, B, Augustin, J, Augustinus, A, Baillon, P, Bambade, P, Barao, F, Barate, R
Format: Journal article
Language:English
Published: 1996
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author Abreu, P
Adam, W
Adye, T
Agasi, E
Ajinenko, I
Aleksan, R
Alekseev, G
Alemany, R
Allport, P
Almehed, S
Alvsvaag, S
Amaldi, U
Amato, S
Andreazza, A
Andrieux, M
Antilogus, P
Apel, W
Arnoud, Y
Asman, B
Augustin, J
Augustinus, A
Baillon, P
Bambade, P
Barao, F
Barate, R
author_facet Abreu, P
Adam, W
Adye, T
Agasi, E
Ajinenko, I
Aleksan, R
Alekseev, G
Alemany, R
Allport, P
Almehed, S
Alvsvaag, S
Amaldi, U
Amato, S
Andreazza, A
Andrieux, M
Antilogus, P
Apel, W
Arnoud, Y
Asman, B
Augustin, J
Augustinus, A
Baillon, P
Bambade, P
Barao, F
Barate, R
author_sort Abreu, P
collection OXFORD
description Three jet events arising from decays of the Z boson, collected by the DELPHI detector, were used to measure differences in quark and gluon fragmentation. Gluon jets were anti-tagged by identifying b quark jets. Unbiased quark jets came from events with two jets plus one photon. Quark and gluon jet properties in different energy ranges were compared for the first time within the same detector. Quark and gluon jets of nearly the same energy in symmetric three jet event topologies were also compared. Using three independent methods, the average value of the ratio of the mean charged multiplicities of gluon and quark jets is 〈 r 〉= 1.241 ± 0.015 (stat.) ± 0.025 (syst.). Gluon jets are broader and produce fragments with a softer energy spectrum than quark jets of equivalent energy. The string effect has been observed in fully symmetric three jet events. The measured ratio Rγ of the charged particle flow in the qq̄ inter-jet region of the qq̄g and qq̄γ samples agrees with the perturbative QCD expectation. The dependence of the mean charged multiplicity on the hadronic center-of-mass energy was analysed in photon plus n-jet events. The value for αs(MZ) determined from these data using a QCD prediction with corrections at leading and next-to-leading order is αs(MZ) = 0.116 ± 0.003 (stat.) ± 0.009 (syst.). © Springer-Verlag 1996.
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spelling oxford-uuid:9754f71e-54af-4485-96d8-5f792d5ad3902022-03-26T23:58:48ZEnergy dependence of the differences between the quark and gluon jet fragmentationJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:9754f71e-54af-4485-96d8-5f792d5ad390EnglishSymplectic Elements at Oxford1996Abreu, PAdam, WAdye, TAgasi, EAjinenko, IAleksan, RAlekseev, GAlemany, RAllport, PAlmehed, SAlvsvaag, SAmaldi, UAmato, SAndreazza, AAndrieux, MAntilogus, PApel, WArnoud, YAsman, BAugustin, JAugustinus, ABaillon, PBambade, PBarao, FBarate, RThree jet events arising from decays of the Z boson, collected by the DELPHI detector, were used to measure differences in quark and gluon fragmentation. Gluon jets were anti-tagged by identifying b quark jets. Unbiased quark jets came from events with two jets plus one photon. Quark and gluon jet properties in different energy ranges were compared for the first time within the same detector. Quark and gluon jets of nearly the same energy in symmetric three jet event topologies were also compared. Using three independent methods, the average value of the ratio of the mean charged multiplicities of gluon and quark jets is 〈 r 〉= 1.241 ± 0.015 (stat.) ± 0.025 (syst.). Gluon jets are broader and produce fragments with a softer energy spectrum than quark jets of equivalent energy. The string effect has been observed in fully symmetric three jet events. The measured ratio Rγ of the charged particle flow in the qq̄ inter-jet region of the qq̄g and qq̄γ samples agrees with the perturbative QCD expectation. The dependence of the mean charged multiplicity on the hadronic center-of-mass energy was analysed in photon plus n-jet events. The value for αs(MZ) determined from these data using a QCD prediction with corrections at leading and next-to-leading order is αs(MZ) = 0.116 ± 0.003 (stat.) ± 0.009 (syst.). © Springer-Verlag 1996.
spellingShingle Abreu, P
Adam, W
Adye, T
Agasi, E
Ajinenko, I
Aleksan, R
Alekseev, G
Alemany, R
Allport, P
Almehed, S
Alvsvaag, S
Amaldi, U
Amato, S
Andreazza, A
Andrieux, M
Antilogus, P
Apel, W
Arnoud, Y
Asman, B
Augustin, J
Augustinus, A
Baillon, P
Bambade, P
Barao, F
Barate, R
Energy dependence of the differences between the quark and gluon jet fragmentation
title Energy dependence of the differences between the quark and gluon jet fragmentation
title_full Energy dependence of the differences between the quark and gluon jet fragmentation
title_fullStr Energy dependence of the differences between the quark and gluon jet fragmentation
title_full_unstemmed Energy dependence of the differences between the quark and gluon jet fragmentation
title_short Energy dependence of the differences between the quark and gluon jet fragmentation
title_sort energy dependence of the differences between the quark and gluon jet fragmentation
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