Determining ΔG with Polarized - and Hadroproduction of Heavy Quarks

We present the first calculation of the complete NLO QCD corrections to the production of heavy flavors with longitudinally polarized hadrons. Predictions for the extraction of the gluon helicity density at RHIC using this reaction are made and their theoretical uncertainties are briefly discussed. We also mention the potential of polarized photoproduction of heavy flavors at the EIC project.