Variable accretion outbursts in protostellar evolution

Jaehan Bae, Lee Hartmann, Zhaohuan Zhu, Charles Gammie

Research output: Contribution to journalArticlepeer-review

Abstract

We extend the one-dimensional, two-zone models of long-term protostellar disk evolution with infall of Zhu et al. to consider the potential effects of a finite viscosity in regions where the ionization is too low for the magnetorotational instability (MRI) to operate (the "dead zone"). We find that the presence of a small but finite dead zone viscosity, as suggested by simulations of stratified disks with MRI-active outer layers, can trigger inside-out bursts of accretion, starting at or near the inner edge of the disk, instead of the previously found outside-in bursts with zero dead zone viscosity, which originate at a few AU in radius. These inside-out bursts of accretion bear a qualitative resemblance to the outburst behavior of one FU Ori object, V1515 Cyg, in contrast to the outside-in burst models, which more closely resemble the accretion events in FU Ori and V1057 Cyg. Our results suggest that the type and frequency of outbursts are potentially a probe of transport efficiency in the dead zone. Simulations must treat the inner disk regions, R ≲ 0.5 AU, to show the detailed time evolution of accretion outbursts in general and to observe the inside-out bursts in particular.

Original languageEnglish (US)
Article number141
JournalAstrophysical Journal
Volume764
Issue number2
DOIs
StatePublished - Feb 20 2013

Keywords

  • accretion, accretion disks
  • stars: formation
  • stars: pre-main sequence

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint Dive into the research topics of 'Variable accretion outbursts in protostellar evolution'. Together they form a unique fingerprint.

Cite this