Spin structure of the proton from polarized inclusive deep-inelastic muon-proton scattering

1997/02/12 by D. L. Adams, D. Adams, B. Adeva +98 · 2 citations
Physics and Astronomy · #Condensed matter physics #Dark Matter and Cosmic Phenomena #Deep inelastic scattering #Inelastic scattering #Muon #Muon spin spectroscopy #Nuclear physics #Optics #Particle physics #Particle physics theoretical and experimental studies #Physics #Proton #Proton spin crisis #Quantum Chromodynamics and Particle Interactions #Scattering #Spin (aerodynamics) #Spin structure #hep-ex #hep-ph #nucl-ex

paper · pdf · doi:10.1103/physrevd.56.5330

published as Phys.Rev.D56:5330-5358,1997 · 33 pages, 22 figures, uses ReVTex and smc.sty. submitted to Physical Review D

arxiv created 1997/02/12 · openalex publication_date 1997/11/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

We have measured the spin-dependent structure function g₁^p in inclusive deep-inelastic scattering of polarized muons off polarized protons, in the kinematic range 0.003<x<0.7 and 1GeV²<Q²<60GeV². A next-to-leading order QCD analysis is used to evolve the measured g₁^p(x,Q²) to a fixed Q₀². The first moment of g₁^p at Q₀²=10GeV² is \ensuremathΓ₁^p=0.136\ifmmode±\else\textpm\fi0.013 (stat) \ifmmode±\else\textpm\fi0.009 (syst) \ifmmode±\else\textpm\fi0.005 (evol). This result is below the prediction of the Ellis-Jaffe sum rule by more than two standard deviations. The singlet axial charge a₀ is found to be 0.28\ifmmode±\else\textpm\fi0.16. In the Adler-Bardeen factorization scheme, \ensuremathΔg\ensuremath≃2 is required to bring \ensuremathΔ\ensuremathΣ in agreement with the quark-parton model. A combined analysis of all available proton, deuteron, and ³He data confirms the Bjorken sum rule.

Citations

• Asymptotic freedom in parton language
• Padé approximants, Borel transforms and renormalons: the Bjorken sum rule as a case study
• Observations of the Failure of Conservation of Parity and Charge Conjugation in Meson Decays: the Magnetic Moment of the Free Muon
• Measurement of neutrino-proton and antineutrino-proton elastic scattering
• The spin dependence of diffractive processes and implications for the small x behaviour of g1 and the spin content of the nucleon
• Measurement of the spin-dependent structure function g1(x) of the proton

Cited by

• Nucleon structure functions and longitudinal spin asymmetries in the chiral quark constituent model
• Current tensor with a heavy photon for pair production by a longitudinally polarized electron