Flavour separation of helicity distributions from deep inelastic muon-deuteron scattering

Journal Article (Journal Article)

We present a LO evaluation of helicity densities of valence, Δ u v + Δ d v, non-strange sea, Δ over(u, ̄) + Δ over(d, ̄), and strange quarks, Δs (assumed to be equal to Δ over(s, ̄)). They have been obtained from the inclusive asymmetry A 1, d and the semi-inclusive asymmetries A 1, dπ +, A 1, dπ -, A 1, dK +, A 1, dK - measured in polarised deep inelastic muon-deuteron scattering. The full deuteron statistics of COMPASS (years 2002-2004 and 2006) has been used. The data cover the range Q 2 > 1   (GeV / c) 2 and 0.004 < x < 0.3. Both non-strange densities are found to be in a good agreement with previous measurements. The distribution of Δ s (x) is compatible with zero in the whole measured range, in contrast to the shape of the strange quark helicity distribution obtained in most LO and NLO QCD fits. The sensitivity of the values of Δ s (x) upon the choice of fragmentation functions used in the derivation is discussed. © 2009 Elsevier B.V. All rights reserved.

Full Text

Duke Authors

Cited Authors

  • Alekseev, M; Alexakhin, VY; Alexandrov, Y; Alexeev, GD; Amoroso, A; Austregesilo, A; Badełek, B; Balestra, F; Ball, J; Barth, J; Baum, G; Bedfer, Y; Bernhard, J; 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; Chung, SU; Cicuttin, A; Colantoni, M; Crespo, ML; Torre, SD; Dafni, T; Das, S; Dasgupta, SS; Denisov, OY; Dhara, L; Diaz, V; Dinkelbach, AM; Donskov, SV; Doshita, N; Duic, V; Dünnweber, W; Efremov, A; El Alaoui, A; Eversheim, PD; Eyrich, W; Faessler, M; Ferrero, A; Finger, M; Fischer, H; Franco, C; Friedrich, JM; Garfagnini, R; Gautheron, F; Gavrichtchouk, OP; Gazda, R; Gerassimov, S; Geyer, R; Giorgi, M; Gobbo, B; Goertz, S; Grabmüller, S; Grajek, OA; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Haas, F; Hagemann, R; von Harrach, D; Hasegawa, T; Heckmann, J; Heinsius, FH; Hermann, R; Herrmann, F; Heß, C; Hinterberger, F; Horikawa, N; Höppner, C; d'Hose, N; Ilgner, C; Ishimoto, S; Ivanov, O; Ivanshin, Y; Iwata, T; Jahn, R; Jasinski, P; Jegou, G; Joosten, R; Kabuß, E; Käfer, W; Kang, D; Ketzer, B; Khaustov, GV; Khokhlov, YA; Kiefer, J; Kisselev, Y; Klein, F; Klimaszewski, K

Published Date

  • September 28, 2009

Published In

Volume / Issue

  • 680 / 3

Start / End Page

  • 217 - 224

International Standard Serial Number (ISSN)

  • 0370-2693

Digital Object Identifier (DOI)

  • 10.1016/j.physletb.2009.08.065

Citation Source

  • Scopus