The Importance of Luminosity Outbursts in Building Low-Mass Stars
Abstract
During the formation of a low-mass star, gas accretes from the protoplanetary disk onto the star both in episodic bursts and in steady, slowly varying flows. We investigate what fraction of a typical star's ultimate main-sequence mass is attributable to each mode. This has implications for the evolution of accretion onto protostars, the properties of stars as they transition from protostars to pre-main-sequence stars, and the evolution of disks being heated by the bursts. We update our ongoing study of outbursts among 319 Orion protostars with new data on the known events in HOPS 223 (V2775 Ori) and HOPS 383 and with the discovery of two additional outburst candidates via the Spitzer program "Orion: The Final Epoch." Our previously reported estimate of about 1000 yr between outbursts in each protostar remains unchanged with the addition of two new outbursts over a longer time baseline. Under a range of assumptions, we estimate that more than 25% of a star's main-sequence mass is attributable to outbursts. We discuss a strategy for refining these estimates further with a campaign by the proposed Origins Space Telescope.
- Publication:
-
American Astronomical Society Meeting Abstracts #233
- Pub Date:
- January 2019
- Bibcode:
- 2019AAS...23315503F