2008/02/29 by Y. Prok, P. Bosted, V. D. Burkert +98 · 54 citations
Physics and Astronomy · #Atomic physics #Chiral perturbation theory #Deuterium #Electron #Molecule #Nuclear physics #Nuclear physics research studies #Particle physics #Particle physics theoretical and experimental studies #Physics #Polarizability #Proton #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #nucl-ex
paper · pdf · doi:10.1016/j.physletb.2008.12.063
published in Physics Letters B 672(1), 12-16 (Elsevier BV) · Final version as published in PLB. Added a parametrization of world data at high Q^2 to Fig. 3
openalex publication_date 2009/01/08 · arxiv created 2009/06/08 · arxiv updated 2010/04/06 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The spin structure functions g1 for the proton and the deuteron have been measured over a wide kinematic range in x and Q2 using 1.6 and 5.7 GeV longitudinally polarized electrons incident upon polarized NH3 and ND3 targets at Jefferson Lab. Scattered electrons were detected in the CEBAF Large Acceptance Spectrometer, for 0.05<Q2<5 GeV2 and W<3 GeV. The first moments of g1 for the proton and deuteron are presented – both have a negative slope at low Q2, as predicted by the extended Gerasimov–Drell–Hearn sum rule. The first extraction of the generalized forward spin polarizability of the proton γ0p is also reported. This quantity shows strong Q2 dependence at low Q2. Our analysis of the Q2 evolution of the first moment of g1 shows agreement in leading order with Heavy Baryon Chiral Perturbation Theory. However, a significant discrepancy is observed between the γ0p data and Chiral Perturbation calculations for γ0p, even at the lowest Q2.