Exclusive ${\pi }^{+}$ electroproduction off the proton from low to high $-t$

Journal Article · 10 December 2019 · Physical Review C

DOI: https://doi.org/10.1103/PhysRevC.100.065204 · OSTI ID:1582308

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, J.; Vulcan, W.; Warren, G.; Wood, S. A.; Xu, C.; Zheng, X.

Background: Measurements of exclusive meson production are a valuable tool in the study of hadronic structure. Specifically, one can discern the relevant degrees of freedom at different distance scales through these studies. Purpose: To study the transition between non-perturbative and perturbative Quantum Chromodyanmics as the square of four momentum transfer to the struck proton, –t, is increased. Method: Cross sections for the ¹H(e,e'π⁺)n reaction were measured over the –t range of 0.272 to 2.127 GeV²with 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 (GPD) based model. Conclusion: The agreement of cross sections with prior data suggests 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.

• Research Organization: Argonne National Laboratory (ANL); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: NSERC; National Science Foundation (NSF); Natural Sciences and Engineering Research Council of Canada (NSERC); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE Office of Science (SC), Nuclear Physics (NP)
• Contributing Organization: Jefferson Lab F(pi)-2 Collaboration
• Grant/Contract Number: AC02-05CH11231; AC02-06CH11357
• OSTI ID: 1582308
• Report Number(s): DOE/OR/23177-4890; JLAB-PHY-19-3125; arXiv:1911.11681
• Journal Information: Physical Review C, Journal Name: Physical Review C Journal Issue: 6 Vol. 100; ISSN PRVCAN; ISSN 2469-9985
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English