Predicting high-$j$, high-energy collisional rate coefficients for the H-CO system using ultracold scattering calculations

Collisional excitation rate coefficients of carbon monoxide with light colliders such as H, H$_{2}$, He, and electrons are necessary to produce accurate models of many astrophysical environments. CO, the second most abundant molecule in the universe after molecular hydrogen, has an excitation temperature of just $\sim$5.5 K for its lowest rotational transition, and so it can be collisionally excited to high rotational levels in moderately energetic environments. However, in these regions it is not appropriate to assume a thermal population of levels, and therefore collisional rate coefficients must be provided to model the non-thermal gas. We present a zero-energy scaling technique for predicting rate coefficients for CO($v=0,j$) deexcitation induced by H for temperatures below 3000 K for transitions from $j=1-70$ to all lower $j'$ levels, where $j$ is the rotational quantum number. We use explicit quantum scattering calculations and our predicted rates to form the most extensive set of collisional excitation rate coefficients for the H-CO system.