The Generalised GDH Sum Rule
The Gerasimov-Drell-Hearn (GDH) sum rule was originally derived for real photon absorption (corresponding to Q{sup 2}=0) and has been generalized to finite Q{sup 2}. The goals of Jefferson Lab experiment E97-110 are to perform a precise measurement of the generalized GDH integral and the moments of the neutron spin structure functions in order to study their Q{sup 2} dependence between 0.02 and 0.3 (GeV/c){sup 2}. This Q{sup 2} range will allow us to extrapolate to the real photon point for {sup 3}He and the neutron. Furthermore the low Q{sup 2} predictions of Chiral Perturbation Theory and its limits of applicability can be tested. The measurements will provide new constraints on understanding the {sup 3}He and neutron spin structure and contribute to the understanding of the nucleon resonances. The acquisition of data was completed in August of 2003 using the Jefferson Lab high polarization continuous-wave electron beam, the Hall A polarized {sup 3}He target, and the new Hall A septum magnet, which allows measurements at forward angles of 6 and 9 degrees. The status and prospects of the data analysis will be discussed.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE - Office of Energy Research (ER)
- DOE Contract Number:
- AC05-84ER40150
- OSTI ID:
- 885178
- Report Number(s):
- JLAB-PHY-04-279; DOE/ER/40150-3954; TRN: US0603796
- Resource Relation:
- Conference: 58th Scottish University Summer School In Physics: A NATO Advanced Study Institute And EU Hadronic Physics 13 Summer Institute (SUSSP58); 30 Aug - 1 Sep 2004, St. Andrews, Scotland
- Country of Publication:
- United States
- Language:
- English
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