부산대학교 도서관

Protostellar disks are the product of angular momentum conservation during the protostellar collapse. Understanding their formation is crucial because they are the birthplace of planets and because their formation is tightly related to star formation. Unfortunately, the initial properties of Class 0 disks and their evolution are still poorly constrained observationally and theoretically. We aim to better understand the mechanisms that set the statistics of disk properties as well as to study their formation in massive protostellar clumps. We also want to provide the community with synthetic disk populations to better interpret young disk observations. We use the ramses code to model star and disk formation in massive protostellar clumps with MHD including the effect of ambipolar diffusion and RT including the stellar radiative feedback. Those simulations, resolved up to the astronomical unit scale, allow to investigate the formation of disk populations. Magnetic fields play a crucial role in disk formation. A weaker initial field leads to larger and massive disks and weakens the stellar radiative feedback by increasing fragmentation. We find that ambipolar diffusion impacts disk and star formation and leads to very different disk magnetic properties. The stellar radiative feedback also have a strong influence, increasing the temperature and reducing fragmentation. Comparing our disk populations with observations reveals that our models with a mass-to-flux ratio of 10 seems to better reproduce observed disk sizes. This also sheds light on a tension between models and observations for the disk masses. The clump properties and physical modeling impact disk populations significantly. The tension between observations and models for disk mass estimates is critical to solve with synthetic observations in future years, in particular for our comprehension of planet formation.
Comment: 20 pages, 15 figures, accepted for publication in Astronomy & Astrophysics