1. Exclusive $\pi^+$ electroproduction off the proton from low to high-$t$
- Author
-
Basnet, S., Huber, G. M., Li, W. B., Blok, H. P., Gaskell, D., Horn, T., Aniol, K., Arrington, J., Beise, E. J., Boeglin, W., Brash, E. J., Breuer, H., Chang, C. C., Christy, M. E., Ent, R., Gibson, E., Holt, R. J., Jin, S., Jones, M. K., Keppel, C. E., Kim, W., King, P. M., Kovaltchouk, V., Liu, J., Lolos, G. J., Mack, D. J., Margaziotis, D. J., Markowitz, P., Matsumura, A., Meekins, D., Miyoshi, T., Mkrtchyan, H., Niculescu, I., Okayasu, Y., Pentchev, L., Perdrisat, C., Potterveld, D., Punjabi, V., Reimer, P., Reinhold, J., Roche, J., Sarty, A., Smith, G. R., Tadevosyan, V., Tang, L. G., Tvaskis, V., Volmer, Julia, Vulcan, W., Warren, G., Wood, S. A., Xu, C., and Zheng, X.
- Subjects
generalized parton distribution ,accelerator ,background ,momentum transfer ,interference ,parton: distribution function ,electroproduction ,Regge ,nonperturbative ,beam: energy ,kinematics ,meson: production ,structure ,Jefferson Lab ,photoproduction - Abstract
Physical review / C covering nuclear physics C100(6), 065204 (2019). doi:10.1103/PhysRevC.100.065204, Background: Measurements of exclusive meson production are a useful tool in the study of hadronic structure. In particular, one can discern the relevant degrees of freedom at different distance scales through these studies. Purpose: To study the transition between nonperturbative and perturbative quantum chromodynamics as the square of four-momentum transfer to the struck proton, −t, is increased. Method: Cross sections for the H1(e,e′π+)n reaction were measured over the −t range of 0.272 to 2.127 GeV2 with limited azimuthal coverage at fixed beam energy of 4.709 GeV, Q2 of 2.4 GeV2, and W of 2.0 GeV at the Thomas Jefferson National Accelerator Facility (JLab) Hall C. Results: The −t dependence of the measured π+ electroproduction cross section generally agrees with prior data from JLab Halls B and C. The data are consistent with a Regge amplitude-based theoretical model but show poor agreement with a generalized parton distribution–based model. Conclusion: The agreement of cross sections with prior data implies small contribution from the interference terms, and the confirmation of the change in t slopes between the low- and high-−t regions previously observed in photoproduction indicates the changing nature of the electroproduction reaction in our kinematic regime., Published by Inst., Woodbury, NY
- Published
- 2019
- Full Text
- View/download PDF