Exclusive ω meson muoproduction on transversely polarised protons

oleh: C. Adolph, M. Aghasyan, R. Akhunzyanov, M.G. Alexeev, G.D. Alexeev, A. Amoroso, V. Andrieux, N.V. Anfimov, V. Anosov, W. Augustyniak, A. Austregesilo, C.D.R. Azevedo, B. Badełek, F. Balestra, J. Barth, R. Beck, Y. Bedfer, J. Bernhard, K. Bicker, E.R. Bielert, R. Birsa, J. Bisplinghoff, M. Bodlak, M. Boer, P. Bordalo, F. Bradamante, C. Braun, A. Bressan, M. Büchele, W.-C. Chang, C. Chatterjee, M. Chiosso, I. Choi, S.-U. Chung, A. Cicuttin, M.L. Crespo, Q. Curiel, S. Dalla Torre, S.S. Dasgupta, S. Dasgupta, O.Yu. Denisov, L. Dhara, S.V. Donskov, N. Doshita, V. Duic, W. Dünnweber, M. Dziewiecki, A. Efremov, P.D. Eversheim, W. Eyrich, M. Faessler, A. Ferrero, M. Finger, M. Finger Jr., H. Fischer, C. Franco, N. du Fresne von Hohenesche, J.M. Friedrich, V. Frolov, E. Fuchey, F. Gautheron, O.P. Gavrichtchouk, S. Gerassimov, F. Giordano, I. Gnesi, M. Gorzellik, S. Grabmüller, A. Grasso, M. Grosse Perdekamp, B. Grube, T. Grussenmeyer, A. Guskov, F. Haas, D. Hahne, D. von Harrach, R. Hashimoto, F.H. Heinsius, R. Heitz, F. Herrmann, F. Hinterberger, N. Horikawa, N. d'Hose, C.-Y. Hsieh, S. Huber, S. Ishimoto, A. Ivanov, Yu. Ivanshin, T. Iwata, R. Jahn, V. Jary, R. Joosten, P. Jörg, E. Kabuß, B. Ketzer, G.V. Khaustov, Yu.A. Khokhlov, Yu. Kisselev, F. Klein, K. Klimaszewski, J.H. Koivuniemi, V.N. Kolosov, K. Kondo, K. Königsmann, I. Konorov, V.F. Konstantinov, A.M. Kotzinian, O.M. Kouznetsov, M. Krämer, P. Kremser, F. Krinner, Z.V. Kroumchtein, Y. Kulinich, F. Kunne, K. Kurek, R.P. Kurjata, A.A. Lednev, A. Lehmann, M. Levillain, S. Levorato, Y.-S. Lian, J. Lichtenstadt, R. Longo, A. Maggiora, A. Magnon, N. Makins, N. Makke, G.K. Mallot, C. Marchand, B. Marianski, A. Martin, J. Marzec, J. Matoušek, H. Matsuda, T. Matsuda, G.V. Meshcheryakov, M. Meyer, W. Meyer, T. Michigami, Yu.V. Mikhailov, M. Mikhasenko, E. Mitrofanov, N. Mitrofanov, Y. Miyachi, P. Montuenga, A. Nagaytsev, F. Nerling, D. Neyret, V.I. Nikolaenko, J. Nový, W.-D. Nowak, G. Nukazuka, A.S. Nunes, A.G. Olshevsky, I. Orlov, M. Ostrick, D. Panzieri, B. Parsamyan, S. Paul, J.-C. Peng, F. Pereira, M. Pešek, D.V. Peshekhonov, N. Pierre, S. Platchkov, J. Pochodzalla, V.A. Polyakov, J. Pretz, M. Quaresma, C. Quintans, S. Ramos, C. Regali, G. Reicherz, C. Riedl, M. Roskot, D.I. Ryabchikov, A. Rybnikov, A. Rychter, R. Salac, V.D. Samoylenko, A. Sandacz, C. Santos, S. Sarkar, I.A. Savin, T. Sawada, G. Sbrizzai, P. Schiavon, K. Schmidt, H. Schmieden, K. Schönning, S. Schopferer, E. Seder, A. Selyunin, O.Yu. Shevchenko, L. Silva, L. Sinha, S. Sirtl, M. Slunecka, J. Smolik, F. Sozzi, A. Srnka, D. Steffen, M. Stolarski, M. Sulc, H. Suzuki, A. Szabelski, T. Szameitat, P. Sznajder, S. Takekawa, M. Tasevsky, S. Tessaro, F. Tessarotto, F. Thibaud, F. Tosello, V. Tskhay, S. Uhl, J. Veloso, M. Virius, J. Vondra, S. Wallner, T. Weisrock, M. Wilfert, J. ter Wolbeek, K. Zaremba, P. Zavada, M. Zavertyaev, E. Zemlyanichkina, M. Ziembicki, A. Zink

Format: Article
Diterbitkan: Elsevier 2017-02-01

Deskripsi

Exclusive production of ω mesons was studied at the COMPASS experiment by scattering 160 GeV/c muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured in the range of photon virtuality 1 (GeV/c)2<Q2<10 (GeV/c)2, Bjorken scaling variable 0.003<xBj<0.3 and transverse momentum squared of the ω meson 0.05 (GeV/c)2<pT2<0.5 (GeV/c)2. The measured asymmetries are sensitive to the nucleon helicity-flip Generalised Parton Distributions (GPD) E that are related to the orbital angular momentum of quarks, the chiral-odd GPDs HT that are related to the transversity Parton Distribution Functions, and the sign of the πω transition form factor. The results are compared to recent calculations of a GPD-based model.