TAP Dynamics Initiative Special Talk, Munan Gong

Abstract:  Thermodynamics and chemistry play important roles for regulating the dynamics and observational molecular tracers of the ISM, yet MHD simulations of star and planet formation often neglect them. In this talk, I will present two recent projects that highlight the importance of correctly accounting for the interaction between thermodynamics, chemistry, and magnetohydrodynamics in protoplanetary disks and molecular clouds. First, I will show that shocks can be generated in the circumbinary disks from binary interactions, explaining the observed hot spots and hot corinos around young protostars. Second, I will present our result on modeling the turbulent diffuse molecular cloud with self-consisitent chemistry, showing that accounting for time-dependent chemistry lowers the derived cosmic-ray ionization rate from H3+ observations by a factor of 2-10. These results were achieved using our new chemistry module for the Athena++ MHD code, which is publicly available.