I am an expert in modeling Photodissociation Regions (PDRs). These are clouds of gas where ultraviolet radiation from massive stars affect both the chemistry and heating. At the cloud surface there is mainly atomic gas, but deeper in, molecular H2 can form, followed by CO and more complex molecules. The gas is heating mainly by photoelectric ejection of electrons from grains and cooled by infrared radiation from fine-structure levels of atoms and by radio radiation from rotation of molecules. I have applied my models to analyze the temperature, density, composition, and incident radiation field in star forming regions and diffuse gas in our Galaxy and in other galaxies.

Research Areas:

Star Formation & The Interstellar Medium