Exclusive electroproduction of J/psi mesons at HERA

Chekanov, S. et al. (2004) Exclusive electroproduction of J/psi mesons at HERA. Nuclear Physics B, 695(1-2), pp. 3-37. (doi: 10.1016/j.nuclphysb.2004.06.034)

Abstract

The exclusive electroproduction of J/psi mesons, ep → epJ/psi, has been studied with the ZEUS detector at HERA for virtualities of the exchanged photon in the ranges 0.15 lt Q(2) lt 0.8 GeV2 and 2 lt Q(2) lt 100 GeV2 using integrated luminosities of 69 and 83 pb(-1), respectively. The photonproton centre-of-mass energy was in the range 30 lt W lt 220 GeV and the squared four-momentum transfer at the proton vertex \t\ lt 1 GeV2. The cross sections and decay angular distributions are presented as functions of Q(2), W and t. The effective parameters of the pomeron trajectory are in agreement with those found in J/psi photoproduction. The spin-density matrix elements, calculated from the decay angular distributions, are consistent with the hypothesis of s-channel helicity conservation. The ratio of the longitudinal to transverse cross sections, sigma(L)/sigma(T), grows with Q(2), whilst no dependence on W or t is observed. The results are in agreement with perturbative QCD calculations and exhibit a strong sensitivity to the gluon distribution in the proton.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Ferrando, Dr James and Saxon, Professor David and Bussey, Dr Peter and Doyle, Professor Anthony
• Authors: Chekanov, S., Derrick, A., Loizides, J.H., Magill, S., Miglioranzi, S., Musgrave, B., Repond, J., Yoshida, R., Mattingly, M.C.K., Pavel, N., Antonioli, P., Bari, G., Basile, M., Bellagamba, L., Boscherini, D., Bruni, A., Bruni, G., Romeo, G.C., Cifarelli, L., Clindolo, F., Contin, A., Corradi, M., De Pasquale, S., Giusti, P., Iacobucci, G., Margotti, A., Montanari, A., Nania, R., Palmonari, F., Pesci, A., Rinaldi, L., Sartorelli, G., Zichichi, A., Aghuzumtsyan, G., Bartsch, D., Brock, I., Goers, S., Hartmann, H., Hilger, E., Irrgang, P., Jakob, H.P., Kind, O., Meyer, U., Paul, E., Rautenberg, J., Renner, R., Stifutkin, A., Tandler, J., Voss, K.C., Wang, M., Bailey, D.S., Brook, N.H., Cole, J.E., Heath, G.P., Namsoo, T., Robins, S., Wing, M., Capua, M., Mastroberardino, A., Schioppa, M., Susinno, G., Kim, J.Y., Lim, I.T., Ma, K.J., Pac, M.Y., Helbich, M., Ning, Y., Ren, Z., Schmidke, W.B., Sciulli, F., Chwastowski, J., Eskreys, A., Figiel, J., Galas, A., Olkiewicz, K., Stopa, P., Zawiejski, L., Adamczyk, L., Bold, T., Grabowska-Bold, I., Kisielewska, D., Kowal, A.M., Kowal, M., Lukasik, J., Przybycien, M., Suszycki, L., Szuba, D., Szuba, J., Kotanski, A., Slominski, W., Adler, V., Behrens, U., Bloch, I., Borras, K., Chiochia, V., Dannheim, D., Drews, G., Fourletova, J., Fricke, U., Geiser, A., Gottlicher, P., Gutsche, O., Haas, T., Hain, W., Hillert, S., Horn, C., Kahle, B., Kotz, U., Kowalski, H., Kramberger, G., Labes, H., Lelas, D., Lim, H., Lohr, B., Mankel, R., Melzer-Pellmann, I.A., Nguyen, C.N., Notz, D., Nuncio-Quiroz, A.E., Polini, A., Raval, A., Rurua, L., Schneekloth, U., Stosslein, U., Wolf, G., Youngman, C., Zeuner, W., Schlenstedt, S., Barbagli, G., Gallo, E., Genta, C., Pelfer, P.G., Bamberger, A., Benen, A., Karstens, F., Dobur, D., Vlasov, N.N., Bell, M., Bussey, P.J., Doyle, A.T., Ferrando, J., Hamilton, J., Hanlon, S., Saxon, D.H., Skillicorn, I.O., Gialas, I., Carli, T., Gosau, T., Holm, U., Krumnack, N., Lohrmann, E., Milite, M., Salehi, H., Schleper, P., Schorner-Sadenius, T., Stonjek, S., Wichmann, K., Wick, K., Ziegler, A., Ziegler, A., Collins-Tooth, C., Foudas, C., Goncalo, R., Long, K.R., Tapper, A.D., Cloth, R., Filges, D., Kataoka, P., Nagano, K., Tokushuku, K., Yamada, S., Yamazaki, Y., Barakbaev, A., Boos, E.G., Pokrovskiy, N.S., Zhautykov, B.O., Son, D., Piotrzkowski, K., Barreiro, F., Glasman, C., Gonzalez, O., Labarga, L., del Peso, J., Tassi, E., Terron, J., Zambrana, M., Barbi, M., Corriveau, F., Gliga, S., Lainesse, J., Padhi, S., Stairs, D.G., Walsh, R., Tsurugai, T., Antonov, A., Danilov, P., Dolgoshein, B.A., Gladkov, D., Sosnovtsev, V., Suchkov, S., Dementiev, R.K., Ermolov, R., Katkov, I.I., Khein, L.A., Korzhavina, I.A., Kuzmin, V.A., Levchenko, B.B., Lukina, O.Y., Proskuryakov, A.S., Shcheglova, L.M., Zotkin, S.A., Abt, I., Buttner, C., Caldwell, A., Liu, X., Sutiak, J., Coppola, N., Grijpink, S., Koffeman, E., Kooijman, P., Maddox, E., Pellegrino, A., Schagen, S., Tiecke, H., Vazquez, M., Wiggers, L., de Wolf, E., Brummer, N., Bylsma, B., Durkin, L.S., Ling, T.Y., Cooper-Sarkar, A.M., Cottrell, A., Devenish, R.C.E., Foster, B., Grzelak, G., Gwenlan, C., Kohno, T., Patel, S., Straub, P.B., Walczak, R., Bertolin, A., Brugnera, R., Carlin, R., Dal Corso, F., Dusini, S., Garfagnini, A., Limentani, S., Longhin, A., Parenti, A., Posocco, M., Stanco, L., Turcato, M., Heaphy, E.A., and Metlica, F.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Nuclear Physics B
• ISSN: 0550-3213