Koufalis, P.N. Liepe, M. JACoW Publishing Geneva, Switzerland 978-3-95450-184-7 10.18429/JACoW-IPAC2018-WEPMF041 English 2455-2457 WEPMF041 Contribution to a conference proceedings 2018 2018-06 https://doi.org/10.18429/JACoW-IPAC2018-WEPMF041 http://jacow.org/ipac2018/papers/wepmf041.pdf Previous experiments have shown that introducing nitrogen gas during low temperature bakes (120-160 C) of niobium cavities introduces C, N, and O impurities to the first 10-100 nm of the surface. This new treatment results in higher quality factors and even 'anti-Q-slope' in some cases. However, it is not entirely clear the role that each of these impurities plays in the performance enhancement of the cavities. It has been suggested that interstitial N within the first few nm of the surface is solely responsible for the observed enhancement, but little work has been done on the role of C and O. Because both C and O are abundant in much higher quantities than N near the surface, it is important to understand whether they are beneficial or detrimental to cavity performance. We provide further insight into the effects of C and O on cavity performance by baking in an ambient atmosphere rich in CO2 as opposed to N2.