Determination of the Proton Spin Structure Functions for 0.05 < Q² <5GEV² Using CLAS

Authors

R. G. Fersch
N. Guler, Old Dominion University
P. Bosted
A. Deur
K. Griffioen
C. Keith
S E. KuhnFollow
R. Minehart
Y. Prok, Old Dominion UniversityFollow
K. P. Adhikari
S. Bültmann, Old Dominion UniversityFollow
S. Careccia, Old Dominion University
Gail Dodge, Old Dominion UniversityFollow
V. G. Lagerquist, Old Dominion University
L. B. Weinstein, Old Dominion UniversityFollow

Document Type

Article

Publication Date

2017

DOI

10.1103/PhysRevC.96.065208

Publication Title

Physical Review C.

Volume

96

Issue

065208

Pages

1-34

Abstract

We present the results of our final analysis of the full data set of g^p₁ Q², the spin structure function of the proton, collected using CLAS at Jefferson Laboratory in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.7 GeV were scattered from proton targets ¹⁵NH₃ dynamically polarized along the beam direction) and detected with CLAS. From the measured double spin asymmetries, we extracted virtual photon asymmetries A^p₁ and A^p₂ and spin structure functions g ^p₁ and g^p₂ over a wide kinematic range (0.05 GeV² < Q² < 5 GeV² and 1.08 GeV< W < 3 GeV) and calculated moments of g^p₁. We compare our final results with various theoretical models and expectations, as well as with parametrizations of the world data. Our data, with their precision and dense kinematic coverage, are able to constrain fits of polarized parton distributions, test pQCD predictions for quark polarizations at large x, offer a better understanding of quark-hadron duality, and provide more precise values of higher twist matrix elements in the framework of the operator product expansion.

Original Publication Citation

Fersch, R. G., Guler, N., Bosted, P., Deur, A., Griffioen, K., Keith, C., . . . Collaboration, C. (2017). Determination of the proton spin structure functions for 0.05 < Q² < 5GeV² using CLAS. Physical Review C, 96(065208), 1-34. doi:10.1103/PhysRevC.96.065208

ORCID

0000-0003-2243-6836 (Kuhn), 0000-0002-5680-1814 (Bueltmann), 0000-0003-1582-2376 (Dodge),0000-0001-5416-2900 (Weinstein)

Repository Citation

Fersch, R. G.; Guler, N.; Bosted, P.; Deur, A.; Griffioen, K.; Keith, C.; Kuhn, S E.; Minehart, R.; Prok, Y.; Adhikari, K. P.; Bültmann, S.; Careccia, S.; Dodge, Gail; Lagerquist, V. G.; and Weinstein, L. B., "Determination of the Proton Spin Structure Functions for 0.05 < Q² <5GEV² Using CLAS" (2017). Physics Faculty Publications. 117.
https://digitalcommons.odu.edu/physics_fac_pubs/117