The energetics of turbulent molecular gas and star formation
October 17, 2011
Abstract: Numerical simulations provide an increasingly detailed picture of the build-up of galaxies, but they remain schematic in their description of the dissipative processes which regulate star formation. The mechanical energy released by mergers, gas accretion, the formation of bound systems and feedback must be dissipated for star formation to occur and proceed. Spectroscopic observations of molecular hydrogen with the Spitzer Space Telescope and the SINFONI spectro-imager at ESO are unraveling a key facet of the energetics of galaxy and star formation. They show that the energy dissipation involves a turbulent energy cascade leading to the formation and dynamical heating of H2 gas. I present the physical understanding of the energetics of the multi-phase, turbulent interstellar medium, which arises from the data, highlighting the role interstellar turbulence plays in regulating the star formation efficiency.