What is the fine-grained topic of the following text: In the local universe, the model predicts a CO(10) luminosity function (LF), CO-to-total infrared (IR) luminosity ratios for multiple CO lines and a CO spectral line energy distribution (SLED) which are in good agreement with observations of luminous and ultra-luminous IR galaxies. Only return the topic.
CO Luminosity Function and Ratios in Luminous and Ultra-Luminous IR Galaxies