2006/12/22 by Robi Banerjee, Ralph E. Pudritz · 3 citations
Chemistry · Physics and Astronomy · #Astrophysics and Star Formation Studies #Dust and Plasma Wave Phenomena #Fullerene Chemistry and Applications #astro-ph
paper · pdf · doi:10.1086/512010
published as Astrophys.J.660:479-488,2007 · 22 pages, 12 figures, aastex style, accepted for publication in ApJ, see http://www.ita.uni-heidelberg.de/~banerjee/publications/MassiveStars.pdf for high resolution figures
arxiv created 2006/12/22 · openalex publication_date 2007/04/20 · arxiv updated 2011/02/11 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present an investigation of the massive star formation that results from the gravitational collapse of massive, magnetized molecular cloud cores. We investigate this by means of highly resolved, numerical simulations of initial magnetized Bonnor-Ebert-spheres that undergo collapse and cooling. By comparing three different cases—an isothermal collapse, a collapse with radiative cooling, and a magnetized collapse—we show that massive stars assemble quickly, with mass accretion rates exceeding 10 -3 M ☉ yr -1 . We confirm that the mass accretion during the collapsing phase is much more efficient than predicted by self-similar collapse solutions, i.e., ~ c 3 / G . We find that during protostellar assembly, the mass accretion reaches 20-100 times c 3 / G . Furthermore, we determined the self-consistent structure of the bipolar outflows produced in our three-dimensional magnetized collapse simulations. These outflows produce cavities out of which radiation pressure can be released, thereby reducing the limitations on the final mass of massive stars formed by gravitational collapse. Moreover, we argue that the extraction of angular momentum by disk-threaded magnetic fields and/or by the appearance of bars with spiral arms significantly enhances the mass accretion rate, thereby helping the massive protostar to assemble more quickly.