Measurement of the spin structure function of the neutron from deep inelastic scattering of polarized electrons from polarized neutrons in helium-3

Polarized electrons of energies 19.42, 22.67, and 25.5 GeV were scattered off a polarized $\sp3$He target at SLAC's End Station A to measure the spin asymmetry of the neutron. From this asymmetry, the spin dependent structure function $g\sb1\sp{\rm n}(x)$ was determined over a range in x from 0.03 to 0.6 with an average $Q\sp2$ of 2 (GeV/C)$\sp2$. The value of the integral of $g\sb1\sp{\rm n}$ over x is $\int\limits\sbsp{0}{1}g\sb1\sp{\rm n}(x)dx$ = $-$0.036 $\pm$ 0.009. The results were interpreted in the framework of the Quark Parton Model (QPM) and used to test the Ellis-Jaffe and Bjorken sum rules. The value of the integral is 2.6 standard deviations from the Ellis-Jaffe prediction while the Bjorken sum rule was found to be in agreement with this data and proton data from SMC and E-143.