A Study of Magnetic Fields in the Formation of Molecular Clouds and Stars

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Stars form out of giant clouds of hydrogen, but the details of the collapse are still unclear. The investigators will use computer models to simulate the collapses of clouds to form stars. The investigator seeks to answer three important questions concerning star formation. (1) How much of a cloud turns into stars? (2) How fast does this happen? (3) Are magnetic fields the most important force on collapsing gas? The investigator will produce a series of synthetic observations to hunt for the very first signature of collapsing gas. Star formation of takes millions of years. Astronomer's observations of many clouds in our galaxy are snap shots of the history of star formation. The computer models allow astronomers to organize all these observations into a single story of the birth of stars.The investigator will produce a sequence of synthetic, all-galaxy, maps of molecules and hot gas in our galaxy. The numerical models use adaptive mesh refinement and include the effects of magnetic fields, radiation feedback, and models for the chemical composition of the clouds. The open source code ENZO will be used for the simulations. The simulations have a physical scale of 1000 pc and resolution of 100 astronomical units. The investigator will start with initial conditions similar to those seen in the stratified galactic disk. At higher linear resolution, the simulation will be concentrated on molecular clouds and the dense cores that harbor young stars. The complete assembly history of forces and observational signatures will be produced.