Measurement of the Q^2 Dependence of the Deuteron Spin Structure Function g_1 and its Moments at Low Q^2 with CLAS

Abstract

We measured the $g_1$ spin structure function of the deuteron at low $Q^2$, where QCD can be approximated with chiral perturbation theory ($\chi$PT). The data cover the resonance region, up to an invariant mass of $W\approx 1.9$~GeV. The generalized Gerasimov-Drell-Hearn sum, the moment ${\bar{\Gamma }}_1^d$ and the integral ${\bar{I}}_{\gamma }^d$ related to the spin polarizability ${\gamma }_0^d$ are precisely determined down to a minimum $Q^2$ of 0.02~GeV${}^2$ for the first time, about 2.5 times lower than that of previous data. We compare them to several $\chi$PT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the $\chi$PT domain.

arXiv commentVersion 1: version published in Phys. Rev. Lett. 6 pages, 3 figures. Supplementary material: data table for g1d and its moments (10 pages) V2: Figures labels changed and text slightly modified to clarify the exact nature of the measured moments V3: Corrected a typo page 5 for the theoretical value expected for deuteron GDH sum rule (agreement between measurement and expectation is improved)

References in corpus (34)

• A unitary isobar model for pion photo- and electroproduction on the proton up to 1 GeV
• The Spin Structure of the Nucleon
• Measurements of the Proton and Deuteron Spin Structure Functions g1 and g2
• Dispersion relations in real and virtual Compton scattering
• Nonperturbative QCD Coupling and its $\beta$ function from Light-Front Holography
• Spin Structure of the Nucleon - Status and Recent Results
• First measurement of the Gerasimov-Drell-Hearn integral for Hydrogen from 200 to 800 MeV
• Virtual Compton Scattering and Generalized Polarizabilities of the Proton
• Measurement of the $x$- and $Q^2$-Dependence of the Asymmetry $A_1$ on the Nucleon
• Experimental determination of the evolution of the Bjorken integral at low Q^2
• The Q^2 evolution of the generalized Gerasimov-Drell-Hearn integral for the neutron using a He-3 target
• Spin structure of the nucleon at low energies
• Q^2 Evolution of the Neutron Spin Structure Moments using a He-3 Target
• Measurement of the Proton Spin Structure Function $g_1(x,Q^2)$ for $Q^2$ from 0.15 to 1.6 GeV${}^2$ with CLAS
• Generalized Sum Rules for Spin-Dependent Structure Functions of the Nucleon
• Experimental study of isovector spin sum rules
• Generalized Drell-Hearn-Gerasimov Sum Rule at Order {\cal O}(p^4) in Chiral Perturbation Theory
• New insights into the spin structure of the nucleon
• Burkhardt-Cottingham sum rule and forward spin polarizabilities in Heavy Baryon Chiral Perturbation Theory
• Determination of the Proton Spin Structure Functions for 0.05 < Q^2 < 5 GeV^2 using CLAS
• Moments of the Spin Structure Functions g_1^p and g_1^d for 0.05 < Q^2 < 3.0 GeV^2
• Gold-plated moments of nucleon structure functions in baryon chiral perturbation theory
• Measurement of the Generalized Forward Spin Polarizabilities of the Neutron
• Novel analysis of chiral loop effects in the generalized Gerasimov-Drell-Hearn sum rule
• Measurement of Inclusive Spin Structure Functions of the Deuteron
• Precise Determination of the Deuteron Spin Structure at Low to Moderate $Q^2$ with CLAS and Extraction of the Neutron Contribution
• Nucleon spin structure at low momentum transfers
• The Nucleon Spin Polarizability at Order $\mathcal{O}(p^4$) in Chiral Perturbation Theory
• The Gerasimov-Drell-Hearn Sum Rule
• Small Momentum Evolution of the Extended Drell--Hearn--Gerasimov Sum Rule
• Measurements of polarized photo-pion production on longitudinally polarized HD and Implications for Convergence of the GDH Integral
• 3He Spin-Dependent Cross Sections and Sum Rules
• Moments of Spin Structure Functions: Sum Rules and Polarizabilities
• Measurement of Target and Double-spin Asymmetries for the $\vec{e}\vec{p}\to e{\pi }^{+}(n)$ Reaction in the Nucleon Resonance Region at Low $Q^2$

Cited by in corpus (15)

• The Spin Structure of the Nucleon
• The Present and Future of QCD
• Measurement of the Bjorken Sum at very low $Q^2$
• Dispersion Theory in Electromagnetic Interactions
• Forward doubly-virtual Compton scattering off the nucleon in chiral perturbation theory: II. Spin polarizabilities and moments of polarized structure functions
• Measurement of the proton spin structure at long distances
• Measurement of the 3He Spin-Structure Functions and of Neutron (3He) Spin-Dependent Sum Rules at 0.035<Q^2<0.24 GeV^2
• Measurement of the generalized spin polarizabilities of the neutron in the low $Q^2$ region
• $O({\alpha }_s^2$) Polarized Heavy Flavor Corrections}to Deep-Inelastic Scattering at $Q^2\gg m^2$
• Evaluation of Bjorken polarised sum rule with a renormalon-motivated approach
• Single-pion contribution to the Gerasimov--Drell--Hearn sum rule and related integrals
• Measurement of the nucleon spin structure functions for 0.01<$Q^2$<1 GeV${}^2$ using CLAS
• Experimental studies at low $Q^2$ of the spin structure of the nucleon at Jefferson Lab
• The Gerasimov-Drell-Hearn sum-rule with nuclear targets
• Coupled-channel contributions to the GDH sum rule from the Jülich-Bonn approach