FIZIKA B 13 (2004) 1, 57 - 64
JLAB EXPERIMENT 01-006: RESONANCES' SPIN STRUCTURE
OSCAR A. RONDON
Institute of Nuclear and Particle Physics - University of Virginia,
Charlottesville, VA 22901, U.S.A.
E-mail address: email@example.com
Received 26 August 2003; Accepted
26 April 2004
Online 16 July 2004
Experiment 01-006 (Resonances' Spin Structure) was carried out at Jefferson Lab's Hall
C to measure the nucleon spin structure functions in the region of the nucleon resonances.
Longitudinally polarized electrons of 5.76 GeV beam energy were incident on solid
polarized ammonia and deuterated ammonia (15NH3, 15N2H3)
targets. The scattered electrons were detected in the High Momentum Spectrometer parked at
a 13.15° angle relative to the beam. The polarized
target field was used to align the nucleon spins parallel and perpendicular to the beam
helicity to measure the corresponding asymmetries A||
and A^. The measured asymmetries are used to extract
in a model-free way the nucleon spin asymmetries A1(W,Q2) and A2(W,Q2),
which are functions of the invariant mass of the final system, W, and of the four-momentum
transfer, Q2. The measurements extend over 0.8GeV£
W£1.95 GeV and are at an average Q2=1.3 [GeV/c]2.
Preliminary results are shown, including the world's first set of data on the
perpendicular asymmetry of the proton and the deuteron for this kinematic region.
PACS numbers: 13.88.+e, 21.10.Hw, 13.60.Hb
Keywords: nucleon spin, nucleon resonances, polarized electron scattering