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We report on the results of the E06-014 experiment performed at Jefferson Labin Hall A, where a precision measurement of the twist-3 matrix element $d_2$ ofthe neutron ($d_{2}^{n}$) was conducted. This quantity represents the averagecolor Lorentz force a struck quark experiences in a deep inelastic electronscattering event off a neutron due to its interaction with the hadronizingremnants. This color force was determined from a linear combination of thethird moments of the spin structure functions $g_1$ and $g_2$ on $^{3}$He afternuclear corrections had been applied to these moments. The kinematics includedtwo average $Q^{2}$ bins of $3.2$ GeV$^{2}$ and $4.3$ GeV$^{2}$, andBjorken-$x$ $0.25 \leq x \leq 0.90$ covering the DIS and resonance regions. Wefound $d_2^n$ to be small and negative for $<Q^{2}> = 3.2$ GeV$^{2}$, andsmaller for $<Q^{2}> = 4.3$ GeV$^{2}$, consistent with a lattice QCDcalculation. The twist-4 matrix element $f_{2}^{n}$ was extracted by combiningour $d_{2}^{n}$ with the world data on $\Gamma_{1}^{n} = \int_{0}^{1} g_{1}^{n}dx$. We found $f_{2}^{n}$ to be roughly an order of magnitude larger than$d_{2}^{n}$. Utilizing the extracted $d_{2}^{n}$ and $f_{2}^{n}$ data, weseparated the color force into its electric and magnetic components,$F_{E}^{y,n}$ and $F_{B}^{y,n}$, and found them to be equal and opposite inmagnitude, in agreement with instanton model predictions but not with thosefrom QCD sum rules. Additionally, we have extracted the neutron virtualphoton-nucleon asymmetry $A_{1}^{n}$, the structure function ratio$g_{1}^{n}/F_{1}^{n}$, and the quark ratios $(\Delta u + \Delta \bar{u})/(u +\bar{u})$ and $(\Delta d + \Delta \bar{d})/(d + \bar{d})$. These results werefound to be consistent with DIS world data and with the prediction of theconstituent quark model but at odds with those of perturbative QCD at large$x$.

Measurements of $d_{2}^{n}$ and $A_{1}^{n}$: Probing the neutron spin structure