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Title: A Precision Measurement of the Spin Structure Functions f^p_1 and g^g_1

Abstract

In Experiment E155 at the Stanford Linear Accelerator Center, the spin dependent structure function g{sub 1}(x,Q{sup 2}) was measured for both the proton and deuteron. This was accomplished by scattering 48.3 GeV highly polarized electrons (0.813 {+-} 0.020) off polarized {sup 15}NH{sub 3} (proton) and {sup 6}LiD (deuteron) targets. Data were collected in March and April of 1997 using three fixed angle, momentum analyzing spectrometers centered at 2.75{sup o}, 5.5{sup o}, and 10.5{sup o}. This enabled a kinematic coverage of 0.01 < x < 0.9 and 1 GeV{sup 2} < Q{sup 2} < 40 GeV{sup 2}. At an average Q{sup 2} of 5 GeV{sup 2}, the integrals in the measured region were f{sub 0.014}{sup 0.9}g{sub 1}(x)dx = 0.119 {+-} 0.002(stat.) {+-} 0.009(syst.) for the proton and 0.043 {+-} 0.003(stat.) {+-} 0.003(syst.) for the deuteron. Using a perturbative QCD analysis which included a global data set, the results were found to be consistent with the Bjorken Sum Rule. Asymmetry measurements also were made using photoproduced hadrons. Data were collected concurrently with the g{sub 1} data. For the proton, the asymmetries were small and non-zero. The deuteron measurements were consistent with zero.

Authors:
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
839779
Report Number(s):
SLAC-R-735
TRN: US0503472
DOE Contract Number:  
AC02-76SF00515
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ACCURACY; ASYMMETRY; DEUTERONS; ELECTRONS; HADRONS; PROTONS; QUANTUM CHROMODYNAMICS; SCATTERING; SPECTROMETERS; SPIN; STANFORD LINEAR ACCELERATOR CENTER; STRUCTURE FUNCTIONS; SUM RULES; TARGETS

Citation Formats

Toole, T. A Precision Measurement of the Spin Structure Functions f^p_1 and g^g_1. United States: N. p., 2004. Web. doi:10.2172/839779.
Toole, T. A Precision Measurement of the Spin Structure Functions f^p_1 and g^g_1. United States. https://doi.org/10.2172/839779
Toole, T. 2004. "A Precision Measurement of the Spin Structure Functions f^p_1 and g^g_1". United States. https://doi.org/10.2172/839779. https://www.osti.gov/servlets/purl/839779.
@article{osti_839779,
title = {A Precision Measurement of the Spin Structure Functions f^p_1 and g^g_1},
author = {Toole, T},
abstractNote = {In Experiment E155 at the Stanford Linear Accelerator Center, the spin dependent structure function g{sub 1}(x,Q{sup 2}) was measured for both the proton and deuteron. This was accomplished by scattering 48.3 GeV highly polarized electrons (0.813 {+-} 0.020) off polarized {sup 15}NH{sub 3} (proton) and {sup 6}LiD (deuteron) targets. Data were collected in March and April of 1997 using three fixed angle, momentum analyzing spectrometers centered at 2.75{sup o}, 5.5{sup o}, and 10.5{sup o}. This enabled a kinematic coverage of 0.01 < x < 0.9 and 1 GeV{sup 2} < Q{sup 2} < 40 GeV{sup 2}. At an average Q{sup 2} of 5 GeV{sup 2}, the integrals in the measured region were f{sub 0.014}{sup 0.9}g{sub 1}(x)dx = 0.119 {+-} 0.002(stat.) {+-} 0.009(syst.) for the proton and 0.043 {+-} 0.003(stat.) {+-} 0.003(syst.) for the deuteron. Using a perturbative QCD analysis which included a global data set, the results were found to be consistent with the Bjorken Sum Rule. Asymmetry measurements also were made using photoproduced hadrons. Data were collected concurrently with the g{sub 1} data. For the proton, the asymmetries were small and non-zero. The deuteron measurements were consistent with zero.},
doi = {10.2172/839779},
url = {https://www.osti.gov/biblio/839779}, journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Dec 13 00:00:00 EST 2004},
month = {Mon Dec 13 00:00:00 EST 2004}
}