Measurement of the proton $$A_1$$ and $$A_2$$ spin asymmetries. Probing Color Forces
- Temple University, Philadelphia, PA (United States)
The Spin Asymmetries of the Nucleon Experiment (SANE) measured the proton spin structure function $$g_2$$ in a range of Bjorken x, 0.3 < x < 0.8, where extraction of the twist-3 matrix element $$d_2^p$$ (an integral of $$g_2$$ weighted by $x^2$) is most sensitive. The data was taken from $Q^2$ equal to 2.5 $GeV^2$ up to 6.5 $GeV^2$. In this polarized electron scattering off a polarized hydrogen target experiment, two double spin asymmetries, A∥ and A⊥ were measured using the BETA (Big Electron Telescope Array) Detector. BETA consisted of a scintillator hodoscope, gas Cerenkov counter, lucite hodoscope and a large lead glass electromagnetic calorimeter. With a unique open geometry, a threshold gas Cerenkov detector allowed BETA to cleanly identify electrons for this inclusive experiment. A measurement of $$d_2^p$$ is compared to lattice QCD calculations.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Nuclear Physics (NP)
- DOE Contract Number:
- AC05-06OR23177
- OSTI ID:
- 1190860
- Report Number(s):
- JLAB-PHY-15-2094; DOE/OR/23177-3454
- Country of Publication:
- United States
- Language:
- English
Similar Records
Study of Double Spin Asymmetries in Inclusive ep Scattering at Jefferson Lab
Spin Asymmetries on Nucleon Experiment at Jefferson Lab