The polarised valence quark distribution from semi-inclusive DIS Academic Article uri icon

abstract

  • The semi-inclusive difference asymmetry Ah+ - h- for hadrons of opposite charge has been measured by the COMPASS experiment at CERN. The data were collected in the years 2002-2004 using a 160 GeV polarised muon beam scattered off a large polarised 6LiD target in the kinematic range 0.006 < x < 0.7 and 1 < Q2 < 100 (GeV / c)2. In leading order QCD (LO) the deuteron asymmetry Ah+ - h- measures the valence quark polarisation and provides an evaluation of the first moment of uv + dv which is found to be equal to 0.40 0.07 (stat.) 0.06 (syst.) over the measured range of x at Q2 = 10 (GeV / c)2. When combined with the first moment of g1d previously measured on the same data, this result favours a non-symmetric polarisation of light quarks over(u, ) = - over(d, ) at a confidence level of two standard deviations, in contrast to the often assumed symmetric scenario over(u, ) = over(d, ) = over(s, ) = s. 2008 Elsevier B.V. All rights reserved.

published proceedings

  • Physics Letters B

author list (cited authors)

  • Collaboration, C., Alekseev, M., Alexakhin, V. Y., Alexandrov, Y. u., Alexeev, G. D., Amoroso, A., ... Zvyagin, A.

citation count

  • 72

complete list of authors

  • Collaboration, COMPASS||Alekseev, M||Alexakhin, V Yu||Alexandrov, Yu||Alexeev, GD||Amoroso, A||Arbuzov, A||Badełek, B||Balestra, F||Ball, J||Barth, J||Baum, G||Bedfer, Y||Bernet, C||Bertini, R||Bettinelli, M||Birsa, R||Bisplinghoff, J||Bordalo, P||Bradamante, F||Bravar, A||Bressan, A||Brona, G||Burtin, E||Bussa, MP||Chapiro, A||Chiosso, M||Cicuttin, A||Colantoni, M||Costa, S||Crespo, ML||Torre, S Dalla||Dafni, T||Das, S||Dasgupta, SS||De Masi, R||Dedek, N||Denisov, O Yu||Dhara, L||Diaz, V||Dinkelbach, AM||Donskov, SV||Dorofeev, VA||Doshita, N||Duic, V||Dünnweber, W||Eversheim, PD||Eyrich, W||Faessler, M||Falaleev, V||Ferrero, A||Ferrero, L||Finger, M||Finger, M||Fischer, H||Franco, C||Franz, J||Friedrich, JM||Frolov, V||Garfagnini, R||Gautheron, F||Gavrichtchouk, OP||Gazda, R||Gerassimov, S||Geyer, R||Giorgi, M||Gobbo, B||Goertz, S||Gorin, AM||Grabmüller, S||Grajek, OA||Grasso, A||Grube, B||Gushterski, R||Guskov, A||Haas, F||Hannappel, J||von Harrach, D||Hasegawa, T||Heckmann, J||Hedicke, S||Heinsius, FH||Hermann, R||Heß, C||Hinterberger, F||von Hodenberg, M||Horikawa, N||Horikawa, S||d'Hose, N||Ilgner, C||Ioukaev, AI||Ishimoto, S||Ivanov, O||Ivanshin, Yu||Iwata, T||Jahn, R||Janata, A||Jasinski, P||Joosten, R||Jouravlev, NI||Kabuß, E||Kang, D||Ketzer, B||Khaustov, GV||Khokhlov, Yu A||Kisselev, Yu||Klein, F||Klimaszewski, K||Koblitz, S||Koivuniemi, JH||Kolosov, VN||Komissarov, EV||Kondo, K||Königsmann, K||Konorov, I||Konstantinov, VF||Korentchenko, AS||Korzenev, A||Kotzinian, AM||Koutchinski, NA||Kouznetsov, O||Kral, A||Kravchuk, NP||Kroumchtein, ZV||Kuhn, R||Kunne, F||Kurek, K||Ladygin, ME||Lamanna, M||Le Goff, JM||Lednev, AA||Lehmann, A||Levorato, S||Lichtenstadt, J||Liska, T||Ludwig, I||Maggiora, A||Maggiora, M||Magnon, A||Mallot, GK||Mann, A||Marchand, C||Marroncle, J||Martin, A||Marzec, J||Massmann, F||Matsuda, T||Maximov, AN||Meyer, W||Mielech, A||Mikhailov, Yu V||Moinester, MA||Mutter, A||Nagaytsev, A||Nagel, T||Nähle, O||Nassalski, J||Neliba, S||Nerling, F||Neubert, S||Neyret, DP||Nikolaenko, VI||Nikolaev, K||Olshevsky, AG||Ostrick, M||Padee, A||Pagano, P||Panebianco, S||Panknin, R||Panzieri, D||Paul, S||Pawlukiewicz-Kaminska, B||Peshekhonov, DV||Peshekhonov, VD||Piragino, G||Platchkov, S||Pochodzalla, J||Polak, J||Polyakov, VA||Pretz, J||Procureur, S||Quintans, C||Rajotte, J-F||Ramos, S||Rapatsky, V||Reicherz, G||Reggiani, D||Richter, A||Robinet, F||Rocco, E||Rondio, E||Rozhdestvensky, AM||Ryabchikov, DI||Samoylenko, VD||Sandacz, A||Santos, H||Sapozhnikov, MG||Sarkar, S||Savin, IA||Schiavon, P||Schill, C||Schmitt, L||Schönmeier, P||Schröder, W||Shevchenko, O Yu||Siebert, H-W||Silva, L||Sinha, L||Sissakian, AN||Slunecka, M||Smirnov, GI||Sosio, S||Sozzi, F||Srnka, A||Stinzing, F||Stolarski, M||Sugonyaev, VP||Sulc, M||Sulej, R||Tchalishev, VV||Tessaro, S||Tessarotto, F||Teufel, A||Tkatchev, LG||Venugopal, G||Virius, M||Vlassov, NV||Vossen, A||Webb, R||Weise, E||Weitzel, Q||Windmolders, R||Wirth, S||Wiślicki, W||Wollny, H||Zaremba, K||Zavertyaev, M||Zemlyanichkina, E||Zhao, J||Ziegler, R||Zvyagin, A

publication date

  • January 2008