Massive Compact Disks around FU Orionis-type Young Eruptive Stars Revealed by ALMA

Autor(en)
A. Kóspál, Fernando Cruz-Sáenz de Miera, J. A. White, P. Ábrahám, L. Chen, Eduard Vorobiev
Abstrakt

The FU Orionis-type objects (FUors) are low-mass pre-main-sequence stars undergoing a temporary but significant increase of mass accretion rate from the circumstellar disk onto the protostar. It is not yet clear what triggers the accretion bursts and whether the disks of FUors are in any way different from the disks of nonbursting young stellar objects. Motivated by this, we conducted a 1.3 mm continuum survey of 10 FUors and FUor-like objects with ALMA, using both the 7 m array and the 12 m array in two different configurations to recover emission at the widest possible range of spatial scales. We detected all targeted sources and several nearby objects as well. To constrain the disk structure, we fit the data with models of increasing complexity from 2D Gaussian to radiative transfer, enabling comparison with other samples modeled in a similar way. The radiative transfer modeling gives disk masses that are significantly larger than what is obtained from the measured millimeter fluxes assuming optically thin emission, suggesting that the FUor disks are optically thick at this wavelength. In comparison with samples of regular class II and class I objects, the disks of FUors are typically a factor of 2.9-4.4 more massive and a factor of 1.5-4.7 smaller in size. A significant fraction of them (65%-70%) may be gravitationally unstable.

Organisation(en)
Institut für Astrophysik
Externe Organisation(en)
MTA Társadalomtudományi Kutatóközpont, Max-Planck-Institut für Astronomie, Eötvös Loránd University Budapest, National Radio Astronomy Observatory, Charlottesville
Journal
The Astrophysical Journal Supplement Series
Band
256
Anzahl der Seiten
28
ISSN
0067-0049
DOI
https://doi.org/10.3847/1538-4365/ac0f09
Publikationsdatum
10-2021
Peer-reviewed
Ja
ÖFOS 2012
103003 Astronomie, 103004 Astrophysik
Schlagwörter
ASJC Scopus Sachgebiete
Astronomy and Astrophysics, Space and Planetary Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/44fdffe8-5395-4a31-92c0-79a267a316d2