Author/Authors :
Stephen C. Adolph، نويسنده , , M.G. Alekseev، نويسنده , , V.Yu. Alexakhin، نويسنده , , Yu. Alexandrov، نويسنده , , G.D. Alexeev، نويسنده , , A. Amoroso، نويسنده , , A.A. Antonov، نويسنده , , A. Austregesilo، نويسنده , , B. Badelek، نويسنده , , F. Balestra، نويسنده , , J. Barth، نويسنده , , G. Baum، نويسنده , , Y. Bedfer، نويسنده , , L. G. MONGEAU and R. J. BERNHARD، نويسنده , , R. Bertini، نويسنده , , M. Bettinelli، نويسنده , , K. Bicker، نويسنده , , Peter J. Bieling، نويسنده , , R. Birsa، نويسنده , , J. Bisplinghoff، نويسنده , , et al.، نويسنده ,
Abstract :
The transverse target spin azimuthal asymmetry image in hard exclusive production of image mesons was measured at COMPASS by scattering 160 GeV/c muons off transversely polarised protons and deuterons. The measured asymmetry is sensitive to the nucleon helicity-flip generalised parton distributions image, which are related to the orbital angular momentum of quarks in the nucleon. The image, image and image dependence of image is presented in a wide kinematic range: image, image and image for protons or image for deuterons. Results for deuterons are obtained for the first time. The measured asymmetry is small in the whole kinematic range for both protons and deuterons, which is consistent with the theoretical interpretation that contributions from GPDs image and image approximately cancel.
