Deep Exclusive Electroproduction of π^{0} at High Q^{2} in the Quark Valence Regime

M Dlamini; B Karki; S F Ali; P-J Lin; F Georges; H-S Ko; N Israel; M N H Rashad; A Stefanko; D Adikaram; Z Ahmed; H Albataineh; B Aljawrneh; K Allada; S Allison; S Alsalmi; D Androic; K Aniol; J Annand; H Atac; T Averett; C Ayerbe Gayoso; X Bai; J Bane; S Barcus; K Bartlett; V Bellini; R Beminiwattha; J Bericic; D Biswas; E Brash; D Bulumulla; J Campbell; A Camsonne; M Carmignotto; J Castellano; C Chen; J-P Chen; T Chetry; M E Christy; E Cisbani; B Clary; E Cohen; N Compton; J C Cornejo; S Covrig Dusa; B Crowe; S Danagoulian; T Danley; F De Persio; W Deconinck; M Defurne; C Desnault; D Di; M Duer; B Duran; R Ent; C Fanelli; G Franklin; E Fuchey; C Gal; D Gaskell; T Gautam; O Glamazdin; K Gnanvo; V M Gray; C Gu; T Hague; G Hamad; D Hamilton; K Hamilton; O Hansen; F Hauenstein; W Henry; D W Higinbotham; T Holmstrom; T Horn; Y Huang; G M Huber; C Hyde; H Ibrahim; C-M Jen; K Jin; M Jones; A Kabir; C Keppel; V Khachatryan; P M King; S Li; W Li; J Liu; H Liu; A Liyanage; J Magee; S Malace; J Mammei; P Markowitz; E McClellan; F Meddi; D Meekins; K Mesik; R Michaels; A Mkrtchyan; R Montgomery; C Muñoz Camacho; L S Myers; P Nadel-Turonski; S J Nazeer; V Nelyubin; D Nguyen; N Nuruzzaman; M Nycz; O F Obretch; L Ou; C Palatchi; B Pandey; S Park; K Park; C Peng; R Pomatsalyuk; E Pooser; A J R Puckett; V Punjabi; B Quinn; S Rahman; P E Reimer; J Roche; I Sapkota; A Sarty; B Sawatzky; N H Saylor; B Schmookler; M H Shabestari; A Shahinyan; S Sirca; G R Smith; S Sooriyaarachchilage; N Sparveris; R Spies; T Su; A Subedi; V Sulkosky; A Sun; L Thorne; Y Tian; N Ton; F Tortorici; R Trotta; G M Urciuoli; E Voutier; B Waidyawansa; Y Wang; B Wojtsekhowski; S Wood; X Yan; L Ye; Z Ye; C Yero; J Zhang; Y Zhao; P Zhu; Jefferson Lab Hall A Collaboration

doi:10.1103/PhysRevLett.127.152301

Deep Exclusive Electroproduction of π^{0} at High Q^{2} in the Quark Valence Regime

Phys Rev Lett. 2021 Oct 8;127(15):152301. doi: 10.1103/PhysRevLett.127.152301.

Authors

M Dlamini¹, B Karki¹, S F Ali², P-J Lin³, F Georges³, H-S Ko^{3

4}, N Israel¹, M N H Rashad⁵, A Stefanko⁶, D Adikaram⁷, Z Ahmed⁸, H Albataineh⁹, B Aljawrneh¹⁰, K Allada¹¹, S Allison⁵, S Alsalmi¹², D Androic¹³, K Aniol¹⁴, J Annand¹⁵, H Atac¹⁶, T Averett¹⁷, C Ayerbe Gayoso¹⁷, X Bai¹⁸, J Bane¹⁹, S Barcus¹⁷, K Bartlett¹⁷, V Bellini²⁰, R Beminiwattha²¹, J Bericic⁷, D Biswas²², E Brash²³, D Bulumulla⁵, J Campbell²⁴, A Camsonne⁷, M Carmignotto², J Castellano²⁵, C Chen²², J-P Chen⁷, T Chetry¹, M E Christy²², E Cisbani²⁶, B Clary²⁷, E Cohen²⁸, N Compton¹, J C Cornejo^{6

17}, S Covrig Dusa⁷, B Crowe²⁹, S Danagoulian¹⁰, T Danley¹, F De Persio²⁶, W Deconinck¹⁷, M Defurne³⁰, C Desnault³, D Di¹⁸, M Duer²⁸, B Duran¹⁶, R Ent⁷, C Fanelli¹¹, G Franklin⁶, E Fuchey²⁷, C Gal¹⁸, D Gaskell⁷, T Gautam²², O Glamazdin³¹, K Gnanvo¹⁸, V M Gray¹⁷, C Gu¹⁸, T Hague¹², G Hamad¹, D Hamilton¹⁵, K Hamilton¹⁵, O Hansen⁷, F Hauenstein⁵, W Henry¹⁶, D W Higinbotham⁷, T Holmstrom³², T Horn^{2

7}, Y Huang¹⁸, G M Huber⁸, C Hyde⁵, H Ibrahim³³, C-M Jen³⁴, K Jin¹⁸, M Jones⁷, A Kabir¹², C Keppel⁷, V Khachatryan^{7

35

36}, P M King¹, S Li³⁷, W Li⁸, J Liu¹⁸, H Liu³⁸, A Liyanage²², J Magee¹⁷, S Malace⁷, J Mammei³⁹, P Markowitz²⁵, E McClellan⁷, F Meddi²⁶, D Meekins⁷, K Mesik⁴⁰, R Michaels⁷, A Mkrtchyan², R Montgomery¹⁵, C Muñoz Camacho³, L S Myers⁷, P Nadel-Turonski⁷, S J Nazeer²², V Nelyubin¹⁸, D Nguyen¹⁸, N Nuruzzaman²², M Nycz¹², O F Obretch²⁷, L Ou¹¹, C Palatchi¹⁸, B Pandey²², S Park³⁵, K Park⁵, C Peng⁴¹, R Pomatsalyuk³¹, E Pooser⁷, A J R Puckett²⁷, V Punjabi⁴², B Quinn⁶, S Rahman³⁹, P E Reimer⁴³, J Roche¹, I Sapkota², A Sarty⁴⁴, B Sawatzky⁷, N H Saylor⁴⁵, B Schmookler¹¹, M H Shabestari⁴⁶, A Shahinyan⁴⁷, S Sirca⁴⁸, G R Smith⁷, S Sooriyaarachchilage²², N Sparveris¹⁶, R Spies³⁹, T Su¹², A Subedi⁴⁶, V Sulkosky¹¹, A Sun⁶, L Thorne⁶, Y Tian⁴⁹, N Ton¹⁸, F Tortorici²⁰, R Trotta⁵⁰, G M Urciuoli²⁶, E Voutier³, B Waidyawansa⁷, Y Wang¹⁷, B Wojtsekhowski⁷, S Wood⁷, X Yan⁵¹, L Ye⁴⁶, Z Ye¹⁸, C Yero²⁵, J Zhang¹⁸, Y Zhao³⁵, P Zhu⁵²; Jefferson Lab Hall A Collaboration

Affiliations

¹ Ohio University, Athens, Ohio 45701, USA.
² Catholic University of America, Washington, DC 20064, USA.
³ Université Paris-Saclay, CNRS/IN2P3, IJCLab, 91405 Orsay, France.
⁴ Seoul National University, 1 Gwanak-ro, Gwanak-gu, 08826 Seoul, Korea.
⁵ Old Dominion University, Norfolk, Virginia 23529, USA.
⁶ Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
⁷ Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA.
⁸ University of Regina, Regina, Saskatchewan S4S 0A2 Canada.
⁹ Texas A&M University-Kingsville, Kingsville, Texas 78363, USA.
¹⁰ North Carolina Ag. and Tech. State University, Greensboro, North Carolina 27411, USA.
¹¹ Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
¹² Kent State University, Kent, Ohio 44240, USA.
¹³ University of Zagreb, Trg Republike Hrvatske 14, 10000 Zagreb, Croatia.
¹⁴ California State University, Los Angeles, Los Angeles, California 90032, USA.
¹⁵ SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
¹⁶ Temple University, Philadelphia, Pennsylvania 19122, USA.
¹⁷ The College of William and Mary, Williamsburg, Virginia 23185, USA.
¹⁸ University of Virginia, Charlottesville, Virginia 22904, USA.
¹⁹ University of Tennessee, Knoxville, Tennessee 37996, USA.
²⁰ Istituto Nazionale di Fisica Nucleare, Dipt. Di Fisica delle Uni. di Catania, I-95123 Catania, Italy.
²¹ Syracuse University, Syracuse, New York 13244, USA.
²² Hampton University, Hampton, Virginia 23669, USA.
²³ Christopher Newport University, Newport News, Virginia 23606, USA.
²⁴ Dalhousie University, Nova Scotia B3H 4R2, Canada.
²⁵ Florida International University, Miami, Florida 33199, USA.
²⁶ Istituto Nazionale di Fisica Nucleare-Sezione di Roma, P.le Aldo Moro, 2-00185 Roma, Italy.
²⁷ University of Connecticut, Storrs, Connecticut 06269, USA.
²⁸ Tel Aviv University, Tel Aviv 699780 1, Israel.
²⁹ North Carolina Central University, Durham, North Carolina 27707, USA.
³⁰ CEA Saclay, 91191 Gif-sur-Yvette, France.
³¹ Kharkov Institute of Physics and Technology, Kharkov 61108, Ukraine.
³² Randolph Macon College, Ashlan, Virginia 23005, USA.
³³ Cairo University, Cairo 121613, Egypt.
³⁴ Virginia Polytechnic Institute & State University, Blacksburg, Virginia 234061, USA.
³⁵ Stony Brook, State University of New York, New York 11794, USA.
³⁶ Cornell University, Ithaca, New York 14853, USA.
³⁷ University of New Hampshire, Durham, New Hampshire 03824, USA.
³⁸ Columbia University, New York, New York 10027, USA.
³⁹ University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada.
⁴⁰ Rutgers University, New Brunswick, New Jersey 08854, USA.
⁴¹ Duke University, Durham, North Carolina 27708, USA.
⁴² Norfolk State University, Norfolk, Virginia 23504, USA.
⁴³ Physics Division, Argonne National Laboratory, Lemont, Illinois 60439, USA.
⁴⁴ Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada.
⁴⁵ Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
⁴⁶ Mississippi State University, Mississippi State, Mississippi 39762, USA.
⁴⁷ AANL, 2 Alikhanian Brothers Street, 0036 Yerevan, Armenia.
⁴⁸ Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia.
⁴⁹ Shandong University, Jinan, Shandong, 250100, China.
⁵⁰ Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA.
⁵¹ Huangshan University, Huangshan, Anhui, 245041, China.
⁵² University of Science and Technology of China, Hefei, Anhui 230026, China.

PMID: 34678020
DOI: 10.1103/PhysRevLett.127.152301

Abstract

We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x_{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4 GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ_{T}/dt+εdσ_{L}/dt, dσ_{TT}/dt, dσ_{LT}/dt, and dσ_{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t_{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.