Abstract
We are studying the effects of various envelope mass distributions, reaction networks, and rate constants on CO formation in the first month in core-collapse supernovae. We have found that a nonuniform envelope mass distribution does indeed bring the calculated CO abundances closer to the observed values. As a test case of ``clumping'', we have tested envelope density fluctuations that vary approximately sinusoidally with the radius. These fluctuations have tripled the CO production in the deeper areas of the envelope; however, the overall rate is still too low by an order of magnitude. The added density structures have complex effects on the chemical reaction rates, and we are using a 1-D code, so we predict that moving to a fully 3-D radiation transfer scheme and density distribution will bring the CO formation rate up to observed values.
