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Title: Measurement of target and double-spin asymmetries for the e p e π + ( n ) reaction in the nucleon resonance region at low Q 2

Journal Article · · Physical Review C
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We report measurements of target- and double-spin asymmetries for the exclusive channel $$\vec e\vec p\to e\pi^+ (n)$$ in the nucleon resonance region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). These asymmetries were extracted from data obtained using a longitudinally polarized NH$$_3$$ target and a longitudinally polarized electron beam with energies 1.1, 1.3, 2.0, 2.3 and 3.0 GeV. The new results are consistent with previous CLAS publications but are extended to a low $Q^2$ range from $0.0065$ to $0.35$ (GeV$/c$$)$$^2$. The $Q^2$ access was made possible by a custom-built Cherenkov detector that allowed the detection of electrons for scattering angles as low as $$6^\circ$$. These results are compared with the unitary isobar models JANR and MAID, the partial-wave analysis prediction from SAID and the dynamic model DMT. In many kinematic regions our results, in particular results on the target asymmetry, help to constrain the polarization-dependent components of these models.

Research Organization:
George Washington Univ., Washington, DC (United States); Mississippi State Univ., Mississippi State, MS (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Nuclear Physics (NP)
Contributing Organization:
CLAS Collaboration
Grant/Contract Number:
SC0016583; FG02-07ER41528; AC05-06OR23177; ST/L005719/1; GR/T08708/01
OSTI ID:
1439598
Alternate ID(s):
OSTI ID: 1329346; OSTI ID: 1329530
Report Number(s):
JLAB-PHY-16-2307; DOE/OR/-23177-3890; arXiv:1607.03924; PRVCAN; TRN: US1900628
Journal Information:
Physical Review C, Vol. 94, Issue 4; ISSN 2469-9985
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 6 works
Citation information provided by
Web of Science

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Cited By (4)

The spin structure of the nucleon journal June 2019
The spin structure of the nucleon journal January 2005
The spin structure of the nucleon journal January 1994
The Spin Structure of the Nucleon: Proceeding of International School of Nucleon Structure: 1st Course conference April 2017

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