Spin dependent gluon densities from large P photon and dimuon production.

We investigate spin asymmetries in high p photon and dimuon production and show that the spin dependent gluon density can be extracted reliably from pp collisions with these final states. The statement remains true even when the balancing jet is not observed. Hence fixed target experiments can be used to measure the spin dependent gluon density. We also compute the asymmetries in $$p\bar p$$ collisions, and show that the EMC measurement of the spin structure function can be verified and the spin dependent gluon density can be extracted from these experiments. [ABSTRACT FROM AUTHOR]