Measurement of QCD jet broadening in pbar p collisions at √s=1.8 TeV

Abe, F.; Amidei, D.; Apollinari, G.; Ascoli, G.; Atac, M.; Auchincloss, P.; Baden, A.; Barbaro Galtieri, A.; Barnes, V.; Bedeschi, F.; Behrends, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Bensinger, J.; Beretvas, A.; Berge, P.; Bertolucci, S.; Bhadra, S.; Binkley, M.; Blair, R.; Blocker, C.; Bofill, J.; Bolognesi, V.; Booth, A.; Brandenburg, G.; Brown, D.; Byon, A.; Byrum, K.; Campbell, M.; Carey, R.; Carithers, W.; Carlsmith, D.; Carroll, J.; Cashmore, R.; Cervelli, F.; Chadwick, K.; Chapin, T.; Chiarelli, G.; Chinowsky, W.; Cihangir, S.; Cline, D.; Connor, D.; Contreras, M.; Cooper, J.; Cordelli, M.; Curatolo, M.; Day, C.; Delfabbro, R.; Dell'Orso, M.; Demortier, L.; Devlin, T.; Dibitonto, D.; Diebold, R.; Dittus, F.; Divirgilio, A.; Elias, J.; Ely, R.; Errede, S.; Esposito, B.; Feldman, A.; Flaugher, B.; Focardi, Ettore; Foster, G.; Franklin, M.; Freeman, J.; Frisch, H.; Fukui, Y.; Garfinkel, A.; Giannetti, P.; Giokaris, N.; Giromini, P.; Gladney, L.; Gold, M.; Goulianos, K.; Grosso Pilcher, C.; Haber, C.; Hahn, S.; Handler, R.; Harris, R.; Hauser, J.; Hessing, T.; Hollebeek, R.; Hu, P.; Hubbard, B.; Hurst, P.; Huth, J.; Jensen, H.; Johnson, R.; Joshi, U.; Kadel, R.; Kamon, T.; Kanda, S.; Kardelis, D.; Karliner, I.; Kearns, E.; Kephart, R.; Kesten, P.; Keutelian, H.; Kim, S.; Kirsch, L.; Kondo, K.; Kruse, U.; Kuhlmann, S.; Laasanen, A.; Li, W.; Liss, T.; Lockyer, N.; Marchetto, F.; Markeloff, R.; Markosky, L.; Mcintyre, P.; Menzione, A.; Meyer, T.; Mikamo, S.; Miller, M.; Mimashi, T.; Miscetti, S.; Mishina, M.; Miyashita, S.; Mondal, N.; Mori, S.; Morita, Y.; Mukherjee, A.; Newman Holmes, C.; Ng, J.; Nodulman, L.; Paoletti, R.; Para, A.; Patrick, J.; Phillips, T.; Piekarz, H.; Plunkett, R.; Pondrom, L.; Proudfoot, J.; Punzi, G.; Quarrie, D.; Ragan, K.; Redlinger, G.; Rhoades, J.; Rimondi, F.; Ristori, L.; Rohaly, T.; Roodman, A.; Sansoni, A.; Sard, R.; Scarpine, V.; Schlabach, P.; Schmidt, E.; Schoessow, P.; Schub, M.; Schwitters, R.; Scribano, A.; Segler, S.; Sekiguchi, M.; Sestini, P.; Shapiro, M.; Sheaff, M.; Shibata, M.; Shochet, M.; Siegrist, J.; Sinervo, P.; Skarha, J.; Smith, D.; Snider, F.; Denis, R.; Stefanini, A.; Takaiwa, Y.; Takikawa, K.; Theriot, D.; Tollestrup, A.; Tonelli, G.; Trischuk, W.; Tsay, Y.; Ukegawa, F.; Underwood, D.; Vidal, R.; Wagner, R.; Wagner, R.; Walsh, J.; Watts, T.; Webb, R.; Westhusing, T.; White, S.; Wicklund, A.; Williams, H.; Yamanouchi, T.; Yamashita, A.; Yasuoka, K.; Yeh, G.; Yoh, J.; Zetti, F.

doi:10.1103/PhysRevD.44.601

A measurement of the QCD jet-broadening parameter 〈QT〉 is described for high-ET jet data in the central calorimeter of the Collider Detector at Fermilab. As an alternate approach to clustering analysis, this method involves the use of a global event parameter which is free from the ambiguities associated with the definition and separation of individual clusters. The parameter QT is defined as the scalar sum of the transverse momentum perpendicular to the transverse thrust axis. Parton-level QCD predictions are made for 〈QT〉 as a function of ET, the total transverse energy in the events, and suggest that a measurement would show a dependence on the running of the strong coupling constant αs. Comparisons are made to first-order QCD parton-level calculations, as well as to fully evolved and hadronized leading-log simulations. The data are well described by the QCD predictions.

Measurement of QCD jet broadening in pbar p collisions at √s=1.8 TeV / F. Abe, D. Amidei, G. Apollinari, G. Ascoli, M. Atac, P. Auchincloss, A. Baden, A. Barbaro-Galtieri, V. Barnes, F. Bedeschi, S. Behrends, S. Belforte, G. Bellettini, J. Bellinger, J. Bensinger, A. Beretvas, P. Berge, S. Bertolucci, S. Bhadra, M. Binkley, et al.. - In: PHYSICAL REVIEW D. - ISSN 0556-2821. - ELETTRONICO. - 44:(1991), pp. 601-616. [10.1103/PhysRevD.44.601]