The hard science is fine. Basically, what you have is a cold fusion reactor gun. Of course, the major effect of setting up a gluon-range enhancer in a space of air is a fusion of N2 into silicon, and O2 into sulfur. The fused elements precipitate out of the affected sphere, creating a negative air pressure and drawing more air into the sphere to continue the reaction. It's when we start testing with more complex compounds that this gets interesting. Huge macromolecules, like proteins? Giant, super unstable high-atomic number atoms. So, yeah, standing in the path of this thing would be bad. As would hitting a solid block, or crystal.
ETA: I'd hate to imagine the effect of ending up with an atom with an atomic weight of 2 kg.