Grant: Discovery Grants Program - Individual

Gravitational collapse and accretion processes are fundamental to astrophysics, accounting for the formation of stars, planets, black holes, and galaxies. Our group is modeling many of the key steps, including self-consistent disk formation, episodic accretion, and the role of the interstellar magnetic field. A new frontier is the detailed study of magnetic field dissipation through nonideal magnetohydrodynamic (MHD) processes. These processes are crucial to develop a comprehensive understanding of disk formation, accretion, outflow generation, and the facilitation of planet formation. Over the five year period of this grant we will study these processes in three key ways: (1)  development of sophisticated simulations of circumstellar disk formation and evolution that start from the earliest stages of prestellar gravitational collapse and shed light on stellar mass assembly and companion formation during the early life of a protostar; (2) model the early fragmentation phase of a star-forming molecular gas cloud in order to understand the rate of star formation and to make predictions of observational quantities like molecular line spectra and polarized emission that reveals the magnetic field patterns;   (3) model the formation of supermassive stars as the progenitors of supermassive black holes that exist as early as 700 million years after the Big Bang, through numerical simulations of magnetized gravitational collapse and the calculation of observable signatures of their existence. We are firmly in the era of high-resolution and high-sensitivity multiwavelength observations of star formation and the distant universe. The ongoing ALMA (Atacama Large Millimeter/submillimeter Array) era and the nascent JWST (James Webb Space Telescope) era will continue to unravel the secrets of the earliest stages of star formation, when most of the stellar mass is accumulated, circumstellar disks are formed, and the groundwork is laid for planet formation. Numerical simulation power is increasing due to increases in computer speed and parallelism, but also potentially due to new algorithms that utilize novel techniques. We have many international collaborations in place and expect to participate actively in the astronomical community to contribute new insights into the formation of gravitationally-collapsed objects in the universe.