A population of eruptive variable protostars in VVV

C. Contreras Peña, P. W. Lucas, D. Minniti, R. Kurtev, W. Stimson, C. Navarro Molina, J. Borissova, M. S.N. Kumar, M. A. Thompson, T. Gledhill, R. Terzi, D. Froebrich, A. Caratti o Garatti

Research output: Contribution to journalArticlepeer-review

54 Citations (Scopus)

Abstract

We present the discovery of 816 high-amplitude infrared variable stars (ΔKs > 1 mag) in 119 deg2 of the Galactic mid-plane covered by the VISTA Variables in the Via Lactea (VVV) survey. Almost all are new discoveries and about 50 per cent are young stellar objects (YSOs). This provides further evidence that YSOs are the commonest high-amplitude infrared variable stars in the Galactic plane. In the 2010-2014 time series of likely YSOs, we find that the amplitude of variability increases towards younger evolutionary classes (class I and flatspectrum sources) except on short time-scales (< 25 d) where this trend is reversed. Dividing the likely YSOs by light-curve morphology, we find 106 with eruptive light curves, 45 dippers, 39 faders, 24 eclipsing binaries, 65 long-term periodic variables (P > 100 d) and 162 shortterm variables. Eruptive YSOs and faders tend to have the highest amplitudes and eruptive systems have the reddest spectral energy distribution (SEDs). Follow-up spectroscopy in a companion paper verifies high accretion rates in the eruptive systems. Variable extinction is disfavoured by the two epochs of colour data. These discoveries increase the number of eruptive variable YSOs by a factor of at least 5, most being at earlier stages of evolution than the known FUor and EXor types. We find that eruptive variability is at least an order of magnitude more common in class I YSOs than class II YSOs. Typical outburst durations are 1-4 yr, between those of EXors and FUors. They occur in 3-6 per cent of class I YSOs over a 4 yr time span.

Original languageEnglish
Pages (from-to)3011-3038
Number of pages28
JournalMonthly Notices of the Royal Astronomical Society
Volume465
Issue number3
DOIs
Publication statusPublished - 2017

Keywords

  • Herbig Ae/Be
  • Infrared: stars
  • Stars: AGB and post-AGB
  • Stars: low-mass
  • Stars: pre-main-sequence
  • Stars: protostars
  • Stars: variables: T Tauri

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'A population of eruptive variable protostars in VVV'. Together they form a unique fingerprint.

Cite this