The Experts below are selected from a list of 215031 Experts worldwide ranked by ideXlab platform
P L Anthony - One of the best experts on this subject based on the ideXlab platform.
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measurement of the deuteron Spin Structure function g1d x for 1 gev c 2 q2 40 gev c 2
Physics Letters B, 1999Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, T Averett, M C Berisso, S Bultmann, M J Buenerd, T E ChuppAbstract:Abstract New measurements are reported on the deuteron Spin Structure function g1d. These results were obtained from deep inelastic scattering of 48.3 GeV electrons on polarized deuterons in the kinematic range 0.01 6 Li 2 H) as the target material. Extrapolations of the data were performed to obtain moments of g1d, including Γ1d, and the net quark polarization ΔΣ.
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measurements of the proton and deuteron Spin Structure functions g1 and g2
Physical Review D, 1998Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, T Averett, R Antonov, J M BauerAbstract:Measurements are reported of the proton and deuteron Spin Structure functions ${g}_{1}^{p}$ and ${g}_{1}^{d}$ at beam energies of 29.1, 16.2, and 9.7 GeV, and ${g}_{2}^{p}$ and ${g}_{2}^{d}$ at a beam energy of 29.1 GeV. The integrals ${\ensuremath{\Gamma}}_{p}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{p}{(x,Q}^{2})dx$ and ${\ensuremath{\Gamma}}_{d}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{d}{(x,Q}^{2})dx$ were evaluated at fixed ${Q}^{2}=3(\mathrm{GeV}{/c)}^{2}$ using the full data set to yield ${\ensuremath{\Gamma}}_{p}=0.132\ifmmode\pm\else\textpm\fi{}0.003(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009(\mathrm{syst})$ and ${\ensuremath{\Gamma}}_{d}=0.047\ifmmode\pm\else\textpm\fi{}0.003\ifmmode\pm\else\textpm\fi{}0.006.$ The ${Q}^{2}$ dependence of the ratio ${g}_{1}{/F}_{1}$ was studied and found to be small for ${Q}^{2}g1(\mathrm{GeV}{/c)}^{2}.$ Within experimental precision the ${g}_{2}$ data are well described by the twist-2 contribution, ${g}_{2}^{\mathrm{WW}}.$ Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry ${A}_{2}$ was measured and found to be significantly smaller than the positivity limit $\sqrt{R}$ for both proton and deuteron targets. ${A}_{2}^{p}$ is found to be positive and inconsistent with zero. Measurements of ${g}_{1}$ in the resonance region show strong variations with $x$ and ${Q}^{2},$ consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the ${Q}^{2}$ dependence of the integrals ${\ensuremath{\Gamma}}_{p}$ and ${\ensuremath{\Gamma}}_{n}$ below the scaling region.
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P Bogorad, H BorelAbstract:We report on a precision measurement of the neutron Spin Structure function $g^n_1$ using deep inelastic scattering of polarized electrons by polarized ^3He. For the kinematic range 0.014
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P BogoradAbstract:We report on a precision measurement of the neutron Spin Structure function ${g}_{1}^{n}$ using deep inelastic scattering of polarized electrons by polarized ${}^{3}\mathrm{He}$. For the kinematic range $0.014lxl0.7$ and $1l{Q}^{2}l17(\mathrm{GeV}/c{)}^{2}$, we obtain $\ensuremath{\int}{0.014}^{0.7}{g}_{1}^{n}(x)dx\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.036\ifmmode\pm\else\textpm\fi{}0.004(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.005(\mathrm{syst})$ at an average ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5(\mathrm{GeV}/c{)}^{2}$. We find relatively large negative values for ${g}_{1}^{n}$ at low $x$. The results call into question the usual Regge theory method for extrapolating to $x\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ to find the full neutron integral $\ensuremath{\int}{1}^{}{g}_{1}^{n}(x)\mathrm{dx}$, needed for testing the quark-parton model and QCD sum rules.
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deep inelastic scattering of polarized electrons by polarized 3he and the study of the neutron Spin Structure
Physical Review D, 1996Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, Vincent Breton, G D Cates, T E Chupp, F S DietrichAbstract:The neutron longitudinal and transverse asymmetries ${A}_{1}^{n}$ and ${A}_{2}^{n}$ have been extracted from deep inelastic scattering of polarized electrons by a polarized $^{3}\mathrm{He}$ target at incident energies of 19.42, 22.66, and 25.51 GeV. The measurement allows for the determination of the neutron Spin Structure functions ${g}_{1}^{n}(x, {Q}^{2})$ and ${g}_{2}^{n}(x, {Q}^{2})$ over the range $0.03lxl0.6$ at an average ${Q}^{2}$ of 2 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. The data are used for the evaluation of the Ellis-Jaffe and Bjorken sum rules. The neutron Spin Structure function ${g}_{1}^{n}(x, {Q}^{2})$ is small and negative within the range of our measurement, yielding an integral $\ensuremath{\int}{0.03}^{0.6}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.028\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{syst})$. Assuming Regge behavior at low $x$, we extract ${\ensuremath{\Gamma}}_{1}^{n}=\ensuremath{\int}{0}^{1}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.031\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009 (\mathrm{syst})$. Combined with previous proton integral results from SLAC experiment E143, we find ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.160\ifmmode\pm\else\textpm\fi{}0.015$ in agreement with the Bjorken sum rule prediction ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.176\ifmmode\pm\else\textpm\fi{}0.008$ at a ${Q}^{2}$ value of 3 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ evaluated using ${\ensuremath{\alpha}}_{s}=0.32\ifmmode\pm\else\textpm\fi{}0.05$.
T Akagi - One of the best experts on this subject based on the ideXlab platform.
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measurements of the proton and deuteron Spin Structure functions g1 and g2
Physical Review D, 1998Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, T Averett, R Antonov, J M BauerAbstract:Measurements are reported of the proton and deuteron Spin Structure functions ${g}_{1}^{p}$ and ${g}_{1}^{d}$ at beam energies of 29.1, 16.2, and 9.7 GeV, and ${g}_{2}^{p}$ and ${g}_{2}^{d}$ at a beam energy of 29.1 GeV. The integrals ${\ensuremath{\Gamma}}_{p}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{p}{(x,Q}^{2})dx$ and ${\ensuremath{\Gamma}}_{d}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{d}{(x,Q}^{2})dx$ were evaluated at fixed ${Q}^{2}=3(\mathrm{GeV}{/c)}^{2}$ using the full data set to yield ${\ensuremath{\Gamma}}_{p}=0.132\ifmmode\pm\else\textpm\fi{}0.003(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009(\mathrm{syst})$ and ${\ensuremath{\Gamma}}_{d}=0.047\ifmmode\pm\else\textpm\fi{}0.003\ifmmode\pm\else\textpm\fi{}0.006.$ The ${Q}^{2}$ dependence of the ratio ${g}_{1}{/F}_{1}$ was studied and found to be small for ${Q}^{2}g1(\mathrm{GeV}{/c)}^{2}.$ Within experimental precision the ${g}_{2}$ data are well described by the twist-2 contribution, ${g}_{2}^{\mathrm{WW}}.$ Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry ${A}_{2}$ was measured and found to be significantly smaller than the positivity limit $\sqrt{R}$ for both proton and deuteron targets. ${A}_{2}^{p}$ is found to be positive and inconsistent with zero. Measurements of ${g}_{1}$ in the resonance region show strong variations with $x$ and ${Q}^{2},$ consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the ${Q}^{2}$ dependence of the integrals ${\ensuremath{\Gamma}}_{p}$ and ${\ensuremath{\Gamma}}_{n}$ below the scaling region.
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P Bogorad, H BorelAbstract:We report on a precision measurement of the neutron Spin Structure function $g^n_1$ using deep inelastic scattering of polarized electrons by polarized ^3He. For the kinematic range 0.014
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P BogoradAbstract:We report on a precision measurement of the neutron Spin Structure function ${g}_{1}^{n}$ using deep inelastic scattering of polarized electrons by polarized ${}^{3}\mathrm{He}$. For the kinematic range $0.014lxl0.7$ and $1l{Q}^{2}l17(\mathrm{GeV}/c{)}^{2}$, we obtain $\ensuremath{\int}{0.014}^{0.7}{g}_{1}^{n}(x)dx\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.036\ifmmode\pm\else\textpm\fi{}0.004(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.005(\mathrm{syst})$ at an average ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5(\mathrm{GeV}/c{)}^{2}$. We find relatively large negative values for ${g}_{1}^{n}$ at low $x$. The results call into question the usual Regge theory method for extrapolating to $x\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ to find the full neutron integral $\ensuremath{\int}{1}^{}{g}_{1}^{n}(x)\mathrm{dx}$, needed for testing the quark-parton model and QCD sum rules.
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precision measurement of the deuteron Spin Structure function g1d
Physical Review Letters, 1995Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, T Akagi, T Averett, R Antonov, J M Bauer, P BostedAbstract:This work was supported by Department of Energy Contracts No. DE-AC05-84ER40150 (CEBAF), No. W-2795-Eng-48 (LLNL), No. DE-AC0376SF00515 (SLAC), No. DE-FG03-88ER40439 (Stanford), No. DE-FG05-88ER40390 and No. DEFG05-86ER4026 (Virginia), and No. DE-AC02-76ER00881 (Wisconsin); by National Science Foundation Grants No. 9114958 (American), No. 9307710 (Massachusetts), No. 9217979 (Michigan), No. 9104975 (ODU) and No. 9118137 (U. Penn.); by the Schweizersche Nationalfonds (Basel); by the Commonwealth of Virginia (Virginia); by the Centre NAtional de la Recherche Scientifique and the Commissariat a l'Energie Atomique (French groups); and by the Japanese Ministry of Education, Science and Culture (Tohoku).
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precision measurement of the proton Spin Structure function g1p
Physical Review Letters, 1995Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, T Averett, R Antonov, J M Bauer, H BorelAbstract:We have measured the ratio [ital g][sup [ital p]][sub 1]/[ital F][sup [ital p]][sub 1] over the range 0.029[lt][ital x][lt]0.8 and 1.3[lt][ital Q][sup 2][lt]10 (GeV/[ital c])[sup 2] using deep-inelastic scattering of polarized electrons from polarized ammonia. An evaluation of the integral [integral][ital g][sup [ital p]][sub 1]([ital x],[ital Q][sup 2])[ital dx] at fixed [ital Q][sup 2]=3 (GeV/[ital c])[sup 2] yields 0.127[plus minus]0.004(stat)[plus minus]0.010(syst), in agreement with previous experiments, but well below the Ellis-Jaffe sum rule prediction of 0.160[plus minus]0.006. In the quark-parton model, this implies [Delta][ital q]=0.27[plus minus]0.10.
H R Band - One of the best experts on this subject based on the ideXlab platform.
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measurement of the deuteron Spin Structure function g1d x for 1 gev c 2 q2 40 gev c 2
Physics Letters B, 1999Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, T Averett, M C Berisso, S Bultmann, M J Buenerd, T E ChuppAbstract:Abstract New measurements are reported on the deuteron Spin Structure function g1d. These results were obtained from deep inelastic scattering of 48.3 GeV electrons on polarized deuterons in the kinematic range 0.01 6 Li 2 H) as the target material. Extrapolations of the data were performed to obtain moments of g1d, including Γ1d, and the net quark polarization ΔΣ.
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measurements of the proton and deuteron Spin Structure functions g1 and g2
Physical Review D, 1998Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, T Averett, R Antonov, J M BauerAbstract:Measurements are reported of the proton and deuteron Spin Structure functions ${g}_{1}^{p}$ and ${g}_{1}^{d}$ at beam energies of 29.1, 16.2, and 9.7 GeV, and ${g}_{2}^{p}$ and ${g}_{2}^{d}$ at a beam energy of 29.1 GeV. The integrals ${\ensuremath{\Gamma}}_{p}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{p}{(x,Q}^{2})dx$ and ${\ensuremath{\Gamma}}_{d}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{d}{(x,Q}^{2})dx$ were evaluated at fixed ${Q}^{2}=3(\mathrm{GeV}{/c)}^{2}$ using the full data set to yield ${\ensuremath{\Gamma}}_{p}=0.132\ifmmode\pm\else\textpm\fi{}0.003(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009(\mathrm{syst})$ and ${\ensuremath{\Gamma}}_{d}=0.047\ifmmode\pm\else\textpm\fi{}0.003\ifmmode\pm\else\textpm\fi{}0.006.$ The ${Q}^{2}$ dependence of the ratio ${g}_{1}{/F}_{1}$ was studied and found to be small for ${Q}^{2}g1(\mathrm{GeV}{/c)}^{2}.$ Within experimental precision the ${g}_{2}$ data are well described by the twist-2 contribution, ${g}_{2}^{\mathrm{WW}}.$ Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry ${A}_{2}$ was measured and found to be significantly smaller than the positivity limit $\sqrt{R}$ for both proton and deuteron targets. ${A}_{2}^{p}$ is found to be positive and inconsistent with zero. Measurements of ${g}_{1}$ in the resonance region show strong variations with $x$ and ${Q}^{2},$ consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the ${Q}^{2}$ dependence of the integrals ${\ensuremath{\Gamma}}_{p}$ and ${\ensuremath{\Gamma}}_{n}$ below the scaling region.
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P Bogorad, H BorelAbstract:We report on a precision measurement of the neutron Spin Structure function $g^n_1$ using deep inelastic scattering of polarized electrons by polarized ^3He. For the kinematic range 0.014
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P BogoradAbstract:We report on a precision measurement of the neutron Spin Structure function ${g}_{1}^{n}$ using deep inelastic scattering of polarized electrons by polarized ${}^{3}\mathrm{He}$. For the kinematic range $0.014lxl0.7$ and $1l{Q}^{2}l17(\mathrm{GeV}/c{)}^{2}$, we obtain $\ensuremath{\int}{0.014}^{0.7}{g}_{1}^{n}(x)dx\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.036\ifmmode\pm\else\textpm\fi{}0.004(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.005(\mathrm{syst})$ at an average ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5(\mathrm{GeV}/c{)}^{2}$. We find relatively large negative values for ${g}_{1}^{n}$ at low $x$. The results call into question the usual Regge theory method for extrapolating to $x\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ to find the full neutron integral $\ensuremath{\int}{1}^{}{g}_{1}^{n}(x)\mathrm{dx}$, needed for testing the quark-parton model and QCD sum rules.
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deep inelastic scattering of polarized electrons by polarized 3he and the study of the neutron Spin Structure
Physical Review D, 1996Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, Vincent Breton, G D Cates, T E Chupp, F S DietrichAbstract:The neutron longitudinal and transverse asymmetries ${A}_{1}^{n}$ and ${A}_{2}^{n}$ have been extracted from deep inelastic scattering of polarized electrons by a polarized $^{3}\mathrm{He}$ target at incident energies of 19.42, 22.66, and 25.51 GeV. The measurement allows for the determination of the neutron Spin Structure functions ${g}_{1}^{n}(x, {Q}^{2})$ and ${g}_{2}^{n}(x, {Q}^{2})$ over the range $0.03lxl0.6$ at an average ${Q}^{2}$ of 2 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. The data are used for the evaluation of the Ellis-Jaffe and Bjorken sum rules. The neutron Spin Structure function ${g}_{1}^{n}(x, {Q}^{2})$ is small and negative within the range of our measurement, yielding an integral $\ensuremath{\int}{0.03}^{0.6}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.028\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{syst})$. Assuming Regge behavior at low $x$, we extract ${\ensuremath{\Gamma}}_{1}^{n}=\ensuremath{\int}{0}^{1}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.031\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009 (\mathrm{syst})$. Combined with previous proton integral results from SLAC experiment E143, we find ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.160\ifmmode\pm\else\textpm\fi{}0.015$ in agreement with the Bjorken sum rule prediction ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.176\ifmmode\pm\else\textpm\fi{}0.008$ at a ${Q}^{2}$ value of 3 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ evaluated using ${\ensuremath{\alpha}}_{s}=0.32\ifmmode\pm\else\textpm\fi{}0.05$.
R G Arnold - One of the best experts on this subject based on the ideXlab platform.
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measurement of the deuteron Spin Structure function g1d x for 1 gev c 2 q2 40 gev c 2
Physics Letters B, 1999Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, T Averett, M C Berisso, S Bultmann, M J Buenerd, T E ChuppAbstract:Abstract New measurements are reported on the deuteron Spin Structure function g1d. These results were obtained from deep inelastic scattering of 48.3 GeV electrons on polarized deuterons in the kinematic range 0.01 6 Li 2 H) as the target material. Extrapolations of the data were performed to obtain moments of g1d, including Γ1d, and the net quark polarization ΔΣ.
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measurements of the proton and deuteron Spin Structure functions g1 and g2
Physical Review D, 1998Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, T Averett, R Antonov, J M BauerAbstract:Measurements are reported of the proton and deuteron Spin Structure functions ${g}_{1}^{p}$ and ${g}_{1}^{d}$ at beam energies of 29.1, 16.2, and 9.7 GeV, and ${g}_{2}^{p}$ and ${g}_{2}^{d}$ at a beam energy of 29.1 GeV. The integrals ${\ensuremath{\Gamma}}_{p}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{p}{(x,Q}^{2})dx$ and ${\ensuremath{\Gamma}}_{d}={\ensuremath{\int}}_{0}^{1}{g}_{1}^{d}{(x,Q}^{2})dx$ were evaluated at fixed ${Q}^{2}=3(\mathrm{GeV}{/c)}^{2}$ using the full data set to yield ${\ensuremath{\Gamma}}_{p}=0.132\ifmmode\pm\else\textpm\fi{}0.003(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009(\mathrm{syst})$ and ${\ensuremath{\Gamma}}_{d}=0.047\ifmmode\pm\else\textpm\fi{}0.003\ifmmode\pm\else\textpm\fi{}0.006.$ The ${Q}^{2}$ dependence of the ratio ${g}_{1}{/F}_{1}$ was studied and found to be small for ${Q}^{2}g1(\mathrm{GeV}{/c)}^{2}.$ Within experimental precision the ${g}_{2}$ data are well described by the twist-2 contribution, ${g}_{2}^{\mathrm{WW}}.$ Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry ${A}_{2}$ was measured and found to be significantly smaller than the positivity limit $\sqrt{R}$ for both proton and deuteron targets. ${A}_{2}^{p}$ is found to be positive and inconsistent with zero. Measurements of ${g}_{1}$ in the resonance region show strong variations with $x$ and ${Q}^{2},$ consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the ${Q}^{2}$ dependence of the integrals ${\ensuremath{\Gamma}}_{p}$ and ${\ensuremath{\Gamma}}_{n}$ below the scaling region.
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P Bogorad, H BorelAbstract:We report on a precision measurement of the neutron Spin Structure function $g^n_1$ using deep inelastic scattering of polarized electrons by polarized ^3He. For the kinematic range 0.014
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P BogoradAbstract:We report on a precision measurement of the neutron Spin Structure function ${g}_{1}^{n}$ using deep inelastic scattering of polarized electrons by polarized ${}^{3}\mathrm{He}$. For the kinematic range $0.014lxl0.7$ and $1l{Q}^{2}l17(\mathrm{GeV}/c{)}^{2}$, we obtain $\ensuremath{\int}{0.014}^{0.7}{g}_{1}^{n}(x)dx\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}0.036\ifmmode\pm\else\textpm\fi{}0.004(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.005(\mathrm{syst})$ at an average ${Q}^{2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5(\mathrm{GeV}/c{)}^{2}$. We find relatively large negative values for ${g}_{1}^{n}$ at low $x$. The results call into question the usual Regge theory method for extrapolating to $x\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0$ to find the full neutron integral $\ensuremath{\int}{1}^{}{g}_{1}^{n}(x)\mathrm{dx}$, needed for testing the quark-parton model and QCD sum rules.
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deep inelastic scattering of polarized electrons by polarized 3he and the study of the neutron Spin Structure
Physical Review D, 1996Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, Vincent Breton, G D Cates, T E Chupp, F S DietrichAbstract:The neutron longitudinal and transverse asymmetries ${A}_{1}^{n}$ and ${A}_{2}^{n}$ have been extracted from deep inelastic scattering of polarized electrons by a polarized $^{3}\mathrm{He}$ target at incident energies of 19.42, 22.66, and 25.51 GeV. The measurement allows for the determination of the neutron Spin Structure functions ${g}_{1}^{n}(x, {Q}^{2})$ and ${g}_{2}^{n}(x, {Q}^{2})$ over the range $0.03lxl0.6$ at an average ${Q}^{2}$ of 2 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. The data are used for the evaluation of the Ellis-Jaffe and Bjorken sum rules. The neutron Spin Structure function ${g}_{1}^{n}(x, {Q}^{2})$ is small and negative within the range of our measurement, yielding an integral $\ensuremath{\int}{0.03}^{0.6}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.028\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{syst})$. Assuming Regge behavior at low $x$, we extract ${\ensuremath{\Gamma}}_{1}^{n}=\ensuremath{\int}{0}^{1}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.031\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009 (\mathrm{syst})$. Combined with previous proton integral results from SLAC experiment E143, we find ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.160\ifmmode\pm\else\textpm\fi{}0.015$ in agreement with the Bjorken sum rule prediction ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.176\ifmmode\pm\else\textpm\fi{}0.008$ at a ${Q}^{2}$ value of 3 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ evaluated using ${\ensuremath{\alpha}}_{s}=0.32\ifmmode\pm\else\textpm\fi{}0.05$.
H Borel - One of the best experts on this subject based on the ideXlab platform.
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measurement of the deuteron Spin Structure function g1d x for 1 gev c 2 q2 40 gev c 2
Physics Letters B, 1999Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, T Averett, M C Berisso, S Bultmann, M J Buenerd, T E ChuppAbstract:Abstract New measurements are reported on the deuteron Spin Structure function g1d. These results were obtained from deep inelastic scattering of 48.3 GeV electrons on polarized deuterons in the kinematic range 0.01 6 Li 2 H) as the target material. Extrapolations of the data were performed to obtain moments of g1d, including Γ1d, and the net quark polarization ΔΣ.
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precision determination of the neutron Spin Structure function g1n
Physical Review Letters, 1997Co-Authors: P L Anthony, R G Arnold, H R Band, T Akagi, B D Anderson, T Averett, C M Berisso, P Bogorad, H BorelAbstract:We report on a precision measurement of the neutron Spin Structure function $g^n_1$ using deep inelastic scattering of polarized electrons by polarized ^3He. For the kinematic range 0.014
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deep inelastic scattering of polarized electrons by polarized 3he and the study of the neutron Spin Structure
Physical Review D, 1996Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, P Bosted, Vincent Breton, G D Cates, T E Chupp, F S DietrichAbstract:The neutron longitudinal and transverse asymmetries ${A}_{1}^{n}$ and ${A}_{2}^{n}$ have been extracted from deep inelastic scattering of polarized electrons by a polarized $^{3}\mathrm{He}$ target at incident energies of 19.42, 22.66, and 25.51 GeV. The measurement allows for the determination of the neutron Spin Structure functions ${g}_{1}^{n}(x, {Q}^{2})$ and ${g}_{2}^{n}(x, {Q}^{2})$ over the range $0.03lxl0.6$ at an average ${Q}^{2}$ of 2 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$. The data are used for the evaluation of the Ellis-Jaffe and Bjorken sum rules. The neutron Spin Structure function ${g}_{1}^{n}(x, {Q}^{2})$ is small and negative within the range of our measurement, yielding an integral $\ensuremath{\int}{0.03}^{0.6}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.028\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{syst})$. Assuming Regge behavior at low $x$, we extract ${\ensuremath{\Gamma}}_{1}^{n}=\ensuremath{\int}{0}^{1}{g}_{1}^{n}(x)\mathrm{dx}=\ensuremath{-}0.031\ifmmode\pm\else\textpm\fi{}0.006 (\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.009 (\mathrm{syst})$. Combined with previous proton integral results from SLAC experiment E143, we find ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.160\ifmmode\pm\else\textpm\fi{}0.015$ in agreement with the Bjorken sum rule prediction ${\ensuremath{\Gamma}}_{1}^{p}\ensuremath{-}{\ensuremath{\Gamma}}_{1}^{n}=0.176\ifmmode\pm\else\textpm\fi{}0.008$ at a ${Q}^{2}$ value of 3 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^{2}$ evaluated using ${\ensuremath{\alpha}}_{s}=0.32\ifmmode\pm\else\textpm\fi{}0.05$.
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precision measurement of the deuteron Spin Structure function g1d
Physical Review Letters, 1995Co-Authors: P L Anthony, R G Arnold, H R Band, H Borel, T Akagi, T Averett, R Antonov, J M Bauer, P BostedAbstract:This work was supported by Department of Energy Contracts No. DE-AC05-84ER40150 (CEBAF), No. W-2795-Eng-48 (LLNL), No. DE-AC0376SF00515 (SLAC), No. DE-FG03-88ER40439 (Stanford), No. DE-FG05-88ER40390 and No. DEFG05-86ER4026 (Virginia), and No. DE-AC02-76ER00881 (Wisconsin); by National Science Foundation Grants No. 9114958 (American), No. 9307710 (Massachusetts), No. 9217979 (Michigan), No. 9104975 (ODU) and No. 9118137 (U. Penn.); by the Schweizersche Nationalfonds (Basel); by the Commonwealth of Virginia (Virginia); by the Centre NAtional de la Recherche Scientifique and the Commissariat a l'Energie Atomique (French groups); and by the Japanese Ministry of Education, Science and Culture (Tohoku).
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precision measurement of the proton Spin Structure function g1p
Physical Review Letters, 1995Co-Authors: K Abe, P L Anthony, R G Arnold, H R Band, T Akagi, T Averett, R Antonov, J M Bauer, H BorelAbstract:We have measured the ratio [ital g][sup [ital p]][sub 1]/[ital F][sup [ital p]][sub 1] over the range 0.029[lt][ital x][lt]0.8 and 1.3[lt][ital Q][sup 2][lt]10 (GeV/[ital c])[sup 2] using deep-inelastic scattering of polarized electrons from polarized ammonia. An evaluation of the integral [integral][ital g][sup [ital p]][sub 1]([ital x],[ital Q][sup 2])[ital dx] at fixed [ital Q][sup 2]=3 (GeV/[ital c])[sup 2] yields 0.127[plus minus]0.004(stat)[plus minus]0.010(syst), in agreement with previous experiments, but well below the Ellis-Jaffe sum rule prediction of 0.160[plus minus]0.006. In the quark-parton model, this implies [Delta][ital q]=0.27[plus minus]0.10.
