The Q(2) dependence of dijet cross sections in gamma p interactions at HERA

Breitweg, J. et al. (2000) The Q(2) dependence of dijet cross sections in gamma p interactions at HERA. Physics Letters B, 479(1-3), 37 -52. (doi: 10.1016/S0370-2693(00)00311-7)

Abstract

The dependence of the photon structure on the photon virtuality, Q(2), is studied by measuring the reaction e(+) p - → e(+) + jet + jet + X at photon-proton centre-of-mass energies 134 lt W lt 223 GeV. Events have been selected in the Q(2) ranges approximate to 0 GeV2, 0.1-0.55 GeV2, and 1.5-4.5 GeV2, having two jets with transverse energy E-f(jet) gt 5.5 GeV in Ihe Final state. The dijet cross section has been measured as a Function of the fractional momentum of the photon participating in the hard process, x(gamma)(OBS). The ratio of the dijet cross section with x(gamma)(OBS) lt 0.75 to that with x(gamma)(OBS) gt 0.75 decreases as Q(2) increases. The data are compared with the predictions of NLO pQCD and leading-order Monte Carlo programs using various parton distribution functions of the photon. The measurements can be interpreted in terms of a resolved photon component that falls with Q(2) but remains present at values of Q(2) up to 4.5 GeV2. However, none of the models considered gives a good description of the data.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Saxon, Professor David and Bussey, Dr Peter and Doyle, Professor Anthony and Skillicorn, Professor Ian
• Authors: Breitweg, J., Chekanov, S., Derrick, M., Krakauer, D., Magill, S., Musgrave, B., Pellegrino, A., Repond, J., Stanek, R., Yoshida, R., Mattingly, M.C.K., Abbiendi, G., Anselmo, F., Antonioli, P., Bari, G., Basile, M., Bellagamba, L., Boscherini, D., Bruni, A., Bruni, G., Romeo, G.C., Castellini, G., Cifarelli, L., Cindolo, F., Contin, A., Coppola, N., Corradi, M., de Pasquale, S., Giusti, P., Iacobucci, G., Laurenti, G., Levi, G., Margotti, A., Massam, T., Nania, R., Palmonari, F., Pesci, A., Polini, A., Sartorelli, G., Garcia, Y.Z., Zichichi, A., Amelung, C., Bornheim, A., Brock, I., Coboken, K., Crittenden, J., Deffner, R., Hartmann, H., Heinloth, K., Hilger, E., Irrgang, P., Jakob, H.P., Kappes, A., Katz, U.F., Kerger, R., Paul, E., Schnurbusch, H., Stifutkin, A., Tandler, J., Voss, K.C., Weber, A., Wieber, H., Bailey, D.S., Barret, O., Brook, N.H., Foster, B., Heath, G.P., Heath, H.F., McFall, J.D., Piccioni, D., Rodrigues, E., Scott, J., Tapper, R.J., Capua, M., Mastroberardino, A., Schioppa, M., Susinno, G., Jeoung, H.Y., Kim, J.Y., Lee, J.H., Lim, I.T., Ma, K.J., Pac, M.Y., Caldwell, A., Liu, W., Liu, X., Mellado, B., Paganis, S., Sacchi, R., Sampson, S., Sciulli, F., Chwastowski, J., Eskreys, A., Figiel, J., Klimek, K., Olkiewicz, K., Piotrzkowski, K., Przybycien, M.B., Stopa, P., Zawiejski, L., Adamczyk, L., Bednarek, B., Jelen, K., Kisielewska, D., Kowal, A.M., Kowalski, T., Przybycien, M., Rulikowska-Zarebska, E., Suszycki, L., Szuba, D., Kotanski, A., Bauerdick, L.A.T., Behrens, U., Bienlein, J.K., Burgard, C., Desler, K., Drews, G., Fox-Murphy, A., Fricke, U., Goebel, F., Gottlicher, P., Graciani, R., Haas, T., Hain, W., Hartner, G.F., Hasell, D., Hebbel, K., Johnson, K.F., Kasemann, M., Koch, W., Kotz, U., Kowalski, H., Lindemann, L., Lohr, B., Martinez, M., Milite, M., Monteiro, T., Moritz, M., Notz, D., Pelucchi, F., Petrucci, M.C., Rohde, M., Saull, P.R.B., Savin, A.A., Schneekloth, U., Selonke, F., Sievers, M., Stonjek, S., Tassi, E., Wolf, G., Wollmer, U., Youngman, C., Zeuner, W., Coldewey, C., Grabosch, H.J., Viani, A.L.D., Meyer, A., Schlenstedt, S., Straub, P.B., Barbagli, G., Gallo, E., Pelfer, P., Maccarrone, G., Votano, L., Bamberger, A., Benen, A., Eisenhardt, S., Markun, P., Raach, P., Wolfle, S., Bussey, P.J., Doyle, A.T., Lee, S.W., Macdonald, N., McCance, G.J., Saxon, D.H., Sinclair, L.E., Skillicorn, I.O., Waugh, R., Bohnet, I., Gendner, N., Holm, U., Meyer-Larsen, A., Salehi, H., Wick, K., Dannheim, D., Garfagnini, A., Gialas, I., Gladilin, L.K., Kcira, D., Klanner, R., Lohrmann, E., Poelz, G., Zetsche, F., Goncalo, R., Long, K.R., Miller, D.B., Tapper, A.D., Walker, R., Mallik, U., Cloth, P., Filges, D., Ishii, T., Kuze, M., Nagano, K., Tokushuku, K., Yamada, S., Yamazaki, Y., Ahn, S.H., An, S.H., Hong, S.J., Lee, S.B., Nam, S.W., Park, S.K., Lim, H., Park, I.H., Son, D., Barreiro, F., Garcia, G., Glasman, C., Gonzalez, O., Labarga, L., del Peso, J., Redondo, I., Terron, J., Barbi, M., Corriveau, F., Hanna, D.S., Ochs, A., Padhi, S., Riveline, M., Stairs, D.G., Wing, M., Tsurugai, T., Bashkirov, V., Dolgoshein, B.A., Dementiev, R.K., Ermolov, P.F., Golubkov, Y.A., Katkov, I.I., Khein, L.A., Korotkova, N.A., Korzhavina, I.A., Kuzmin, V.A., Lukina, O.Y., Proskuryakov, A.S., Shcheglova, L.M., Solomin, A.N., Vlasov, N.N., Zotkin, S.A., Bokel, C., Botje, M., Brummer, N., Engelen, J., and Grijpink, S.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Physics Letters B
• Publisher: Elsevier BV
• ISSN: 0370-2693
• ISSN (Online): 1873-2445