  To extract information about polarized gluons in the proton, production of
charmed hadrons, in particular, \Lambda_c^+ baryon in pp collisions was
studied. We calculated the transverse momentum distribution and the
pseudo-rapidity distribution of the spin correlation asymmetry A_{LL} between
the initial proton and the produced \Lambda_c^+. Those statistical
sensitivities were also calculated under the condition of RHIC experiment. We
found that the pseudo-rapidity distribution of A_{LL} is promising for testing
the model of polarized gluons in the proton and also the spin-dependent
fragmentation model of a charm quark decaying into \Lambda_c^+ baryon.
