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arXiv · 1003.4549

Measurement of Single and Double Spin Asymmetries in Deep Inelastic Pion Electroproduction with a Longitudinally Polarized Target

The CLAS Collaboration·H. Avakian·P. Bosted·V. D. Burkert·L. Elouadrhiri·K. P. Adhikari·M. Aghasyan·M. Amaryan·M. Anghinolfi·H. Baghdasaryan·J. Ball·M. Battaglieri·I. Bedlinskiy·A. S. Biselli·D. Branford·W. J. Briscoe·W. Brooks·D. S. Carman·L. Casey·P. L. Cole·P. Collins·D. Crabb·V. Crede·A. D'Angelo·A. Daniel·N. Dashyan·R. DeVita·E. DeSanctis·A. Deur·B. Dey·S. Dhamija·R. Dickson·C. Djalali·G. Dodge·D. Doughty·R. Dupre·A. ElAlaoui·P. Eugenio·S. Fegan·R. Fersch·T. A. Forest·A. Fradi·M. Y. Gabrielyan·G. Gavalian·N. Gevorgyan·G. P. Gilfoyle·K. L. Giovanetti·F. X. Girod·W. Gohn·R. W. Gothe·K. A. Griffioen·M. Guidal·N. Guler·L. Guo·K. Hafidi·H. Hakobyan·C. Hanretty·N. Hassall·D. Heddle·K. Hicks·M. Holtrop·Y. Ilieva·D. G. Ireland·E. L. Isupov·S. S. Jawalkar·H. S. Jo·K. Joo·D. Keller·M. Khandaker·P. Khetarpal·W. Kim·A. Klein·F. J. Klein·P. Konczykowski·V. Kubarovsky·S. E. Kuhn·S. V. Kuleshov·V. Kuznetsov·K. Livingston·H. Y. Lu·N. Markov·M. Mayer·J. McAndrew·M. E. McCracken·B. McKinnon·C. A. Meyer·T. Mineeva·M. Mirazita·V. Mokeev·B. Moreno·K. Moriya·B. Morrison·H. Moutarde·E. Munevar·P. Nadel-Turonski·R. Nasseripour·S. Niccolai·G. Niculescu·I. Niculescu·M. R. Niroula
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Abstract

We report the first measurement of the transverse momentum dependence of double spin asymmetries in semi-inclusive production of pions in deep inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Thomas Jefferson National Accelerator Facility (JLab). A significant non-zero $\sin2\phi$ single spin asymmetry was also observed for the first time indicating strong spin-orbit correlations for transversely polarized quarks in the longitudinally polarized proton. The azimuthal modulations of single spin asymmetries have been measured over a wide kinematic range.

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The CLAS Collaboration, H. Avakian, P. Bosted, V. D. Burkert, L. Elouadrhiri, K. P. Adhikari, M. Aghasyan, M. Amaryan, M. Anghinolfi, H. Baghdasaryan, J. Ball, M. Battaglieri, I. Bedlinskiy, A. S. Biselli, D. Branford, W. J. Briscoe, W. Brooks, D. S. Carman, L. Casey, P. L. Cole, P. Collins, D. Crabb, V. Crede, A. D'Angelo, A. Daniel, N. Dashyan, R. DeVita, E. DeSanctis, A. Deur, B. Dey, S. Dhamija, R. Dickson, C. Djalali, G. Dodge, D. Doughty, R. Dupre, A. ElAlaoui, P. Eugenio, S. Fegan, R. Fersch, T. A. Forest, A. Fradi, M. Y. Gabrielyan, G. Gavalian, N. Gevorgyan, G. P. Gilfoyle, K. L. Giovanetti, F. X. Girod, W. Gohn, R. W. Gothe, K. A. Griffioen, M. Guidal, N. Guler, L. Guo, K. Hafidi, H. Hakobyan, C. Hanretty, N. Hassall, D. Heddle, K. Hicks, M. Holtrop, Y. Ilieva, D. G. Ireland, E. L. Isupov, S. S. Jawalkar, H. S. Jo, K. Joo, D. Keller, M. Khandaker, P. Khetarpal, W. Kim, A. Klein, F. J. Klein, P. Konczykowski, V. Kubarovsky, S. E. Kuhn, S. V. Kuleshov, V. Kuznetsov, K. Livingston, H. Y. Lu, N. Markov, M. Mayer, J. McAndrew, M. E. McCracken, B. McKinnon, C. A. Meyer, T. Mineeva, M. Mirazita, V. Mokeev, B. Moreno, K. Moriya, B. Morrison, H. Moutarde, E. Munevar, P. Nadel-Turonski, R. Nasseripour, S. Niccolai, G. Niculescu, I. Niculescu, M. R. Niroula. 2010-03-23. Measurement of Single and Double Spin Asymmetries in Deep Inelastic Pion Electroproduction with a Longitudinally Polarized Target. https://doi.org/10.1103/physrevlett.105.262002

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