Semi-inclusive Lambda_c^+ Leptoproductions and Polarized Gluon Distributions

In order to extract the behavior and magnitude of the spin-dependent gluon distribution, we propose a semi-inclusive $\Lambda_c^+$ production using unpolarized lepton beams and polarized proton targets. The correlation between the target proton spin and the spin of $\Lambda_c^+$ produced in the target fragmentation region might be very effective for testing various models of polarized gluons.