Single-spin azimuthal asymmetries in electroproduction of neutral pions in semi-inclusive deep-inelastic scattering

A. Airapetian, N. Akopov, Z. Akopov, M. Amarian, E. C. Aschenauer, H. Avakian, R. Avakian, A. Avetissian, E. Avetissian, P. Bailey, B. Bains, V. Baturin, C. Baumgarten, M. Beckmann, S. Belostotski, S. Bernreuther, N. Bianchi, H. Böttcher, A. Borissov, O. BouhaliM. Bouwhuis, J. Brack, S. Brauksiepe, W. Brückner, A. Brüll, I. Brunn, H. J. Bulten, G. P. Capitani, P. Chumney, E. Cisbani, G. Ciullo, G. R. Court, P. F. Dalpiaz, R. De Leo, L. De Nardo, E. De Sanctis, D. De Schepper, E. Devitsin, P. K.A. De Witt Huberts, P. Di Nezza, V. Djordjadze, M. Düren, M. Ehrenfried, G. Elbakian, F. Ellinghaus, J. Ely, A. Fantoni, A. Fechtchenko, L. Felawka, B. W. Filippone, H. Fischer, B. Fox, J. Franz, S. Frullani, Y. Gärber, F. Garibaldi, E. Garutti, G. Gavrilov, V. Gharibyan, A. Golendukhin, G. Graw, O. Grebeniouk, P. W. Green, L. G. Greeniaus, A. Gute, W. Haeberli, K. Hafidi, M. Hartig, D. Hasch, D. Heesbeen, F. H. Heinsius, M. Henoch, R. Hertenberger, W. H.A. Hesselink, G. Hofman, Y. Holler, R. J. Holt, B. Hommez, G. Iarygin, A. Izotov, H. E. Jackson, A. Jgoun, P. Jung, R. Kaiser, J. Kanesaka, E. Kinney, A. Kisselev, P. Kitching, H. Kobayashi, N. Koch, K. Königsmann, H. Kolster, V. Korotkov, E. Kotik, V. Kozlov, B. Krauss, V. G. Krivokhijine, G. Kyle, L. Lagamba

Research output: Contribution to journalArticle

208 Citations (Scopus)


A single-spin asymmetry in the azimuthal distribution of neutral pions relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off longitudinally polarized protons. The analyzing power in the sin φ moment of the cross section is 0.019±0.007(stat)±0.003(syst). This result is compared to single-spin asymmetries for charged pion production measured in the same kinematic range. The π0 asymmetry is of the same size as the π+ asymmetry and shows a similar dependence on the relevant kinematic variables. The asymmetry is described by a phenomenological calculation based on a fragmentation function that represents sensitivity to the transverse polarization of the struck quark.

Original languageEnglish
Article number097101
Pages (from-to)971011-971014
Number of pages4
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Issue number9
Publication statusPublished - 1 Nov 2001
Externally publishedYes


ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Cite this

Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Aschenauer, E. C., Avakian, H., Avakian, R., Avetissian, A., Avetissian, E., Bailey, P., Bains, B., Baturin, V., Baumgarten, C., Beckmann, M., Belostotski, S., Bernreuther, S., Bianchi, N., Böttcher, H., Borissov, A., ... Lagamba, L. (2001). Single-spin azimuthal asymmetries in electroproduction of neutral pions in semi-inclusive deep-inelastic scattering. Physical Review D - Particles, Fields, Gravitation and Cosmology, 64(9), 971011-971014. [097101].