What constitutes the spin of the nucleon? The answer to this question is still not completely understood. Although we know the longitudinal quark spin content very well, the data on the transverse quark spin content of the nucleon is still very sparse. Semi-inclusive Deep Inelastic Scattering (SIDIS) using transversely polarized targets provide crucial information on this aspect. The data that is currently available was taken with proton and deuteron targets. The E06-010 experiment was performed at Jefferson Lab in Hall-A to measure the single spin asymmetries in the SIDIS reaction n↑(e,éπ±/K±)X using transversely polarized 3He target. The experiment used the continuous electron beam provided by the CEBAF accelerator with a beam energy of 5.9 GeV. Hadrons were detected in a high-resolution spectrometer in coincidence with the scattered electrons detected by the BigBite spectrometer. The kinematic coverage focuses on the valence quark region, x = 0.19 to 0.34, at Q2 = 1.77 to 2.73 (GeV/c)2. This is the first measurement on a neutron target. The data from this experiment, when combined with the world data on the proton and the deuteron, will provide constraints on the transversity and Sivers distribution functions on both the u and d-quarks in the valence region. In this work we report on the single spin asymmetries in the SIDIS n↑(e,éπ+)X reaction.

We have measured the flavor dependence of multiplicities for $\\pi^+$ and $\\pi^-$ production in semi-inclusive deep-inelastic scattering (SIDIS) on proton and deuteron targets. We used a 10.6 GeV electron beam at Jefferson Lab, and 4 msr solid angle spectrometers (HMS for electrons, SHMS for pions), the lepton vertex spanned the kinematic range $0.3 < x < 0.6$, $2 < Q^2 < 5$ GeV$^2$, and $4 < W^2 < 11$ GeV$^2$. The pion fractional momentum range was $0.3 < z < 0.7$ and the small transverse momentum range was $0 < P_t < .25$ GeV. We used the multiplicities to form sum-and-difference ratios, testing the validity of factorization. We extracted two favored and two unfavored $W$ dependent fragmentation functions (FFs) from these multiplicities. Assuming factorization at low $P_t$, we find that the two ``favored" FFs allow for isospin breaking (charge symmetry violation) at low $W$, while converging to a common value at the highest $W$ of this experiment. The two unfavored FFs are consistent with each other within the experimental uncertainties.