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Title: Deep Exclusive Electroproduction of π 0 at High Q 2 in the Quark Valence Regime

Journal Article · · Physical Review Letters
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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 $$d\sigma_L/dt+\epsilon d\sigma_T/dt$$, $$d\sigma_{TT}/dt$$, $$d\sigma_{LT}/dt$$ and $$d\sigma_{LT'}/dt$$ 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.

Research Organization:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Nuclear Physics (NP); Natural Sciences and Engineering Research Council of Canada (NSERC); Centre National de la Recherche Scientifique (CNRS)
Contributing Organization:
Jefferson Lab Hall A Collaboration
Grant/Contract Number:
AC05-06OR23177; AC02-06CH11357
OSTI ID:
1823682
Alternate ID(s):
OSTI ID: 1824170; OSTI ID: 1869173
Report Number(s):
JLAB-PHY-21-3308; DOE/OR/23177-5114; arXiv:2011.11125; PRLTAO; 152301
Journal Information:
Physical Review Letters, Journal Name: Physical Review Letters Vol. 127 Journal Issue: 15; ISSN 0031-9007
Publisher:
American Physical SocietyCopyright Statement
Country of Publication:
United States
Language:
English

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