1. Precision measurement of the proton and deuteron spin structure functions g2 and asymmetries A2
- Author
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E155 Collaboration, Abe, K., Akagi, T., Anthony, P L., Antonov, R D., Arnold, R G., Averett, T., Band, H R., Bauer, J M., Borel, H., Bosted, P E., Breton, V., Button-Shafer, J., Chen, J P., Chupp, T E., Clendenin, J E., Comptour, C., Coulter, K P., Court, G R., Crabb, D., Daoudi, M., Day, D., Dietrich, F S., Dunne, J., Dutz, H., Erbacher, R D., Fellbaum, J., Feltham, A., Fonvieille, H., Frlez, E., Garvey, D., Gearhart, R A., Gómez, J., Grenier, P., Griffioen, K., Høibraten, S., Hughes, E W., Hyde-Wright, C E., Johnson, J R., Kawall, D., Klein, A., Kuhn, S E., Kuriki, M., Lindgren, R., Liu, T., Lombard-Nelsen, R M., Marroncle, J., Maruyama, T., Maruyama, X K., McCarthy, J., Meyer, W T., Meziani, Z E., Minehart, R C., Mitchell, J., Morgenstern, J., Petratos, G G., Pitthan, R., Pocanic, D., Prescott, C., Prepost, R., Raines, P., Raue, B A., Reyna, D., Rijllart, A., Roblin, Y., Rochester, L S., Rock, S E., Rondon-Aramayo, O A., Sick, I., Smith, L C., Smith, T B., Spengos, M., Staley, F., Steiner, P., Saint-Lorant, S J., Stuart, L M., Suekane, F., Szalata, Z M., Tang, H., Terrien, Y., Usher, T., Walz, D., White, J L., Witte, K., Young, C C., Youngman, B., Yuta, H., Zapalac, G H., Zihlmann, B., Zimmerman, D., and Naval Postgraduate School (U.S.)
- Abstract
The article of record as published may be found at https://doi.org/10.1016/S0370-2693(02)03015-0 We have measured the spin structure functions g2p and g2d and the virtual photon asymmetries A2p and A2d over the kinematic range 0.02 < x < 0.8 and 0.7 < Q^2 < 20 GeV^2 by scattering 29.1 and 32.3 GeV longitudinally polarized electrons from transversely polarized NH3 and 6LiD targets. Our measured g2 approximately follows the twist-2 Wandzura-Wilczek calculation. The twist-3 reduced matrix elements d2p and d2n are less than two standard deviations from zero. The data are inconsistent with the Burkhardt-Cottingham sum rule if there is no pathological behavior as x->0. The Efremov-Leader-Teryaev integral is consistent with zero within our measured kinematic range. The absolute value of A2 is significantly smaller than the sqrt[R(1+A1)/2] limit.
- Published
- 2003