Gaia 18dvy: A New FUor in the Cygnus OB3 Association


Szegedi-Elek E., Abraham P., Wyrzykowski L., Kun M., Kospal A., Chen L., ...More

ASTROPHYSICAL JOURNAL, vol.899, no.2, 2020 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 899 Issue: 2
  • Publication Date: 2020
  • Doi Number: 10.3847/1538-4357/aba129
  • Title of Journal : ASTROPHYSICAL JOURNAL

Abstract

We present optical-infrared photometric and spectroscopic observations of Gaia 18dvy, located in the Cygnus OB3 association at a distance of 1.88 kpc. Gaia 18dvy was noted by the Gaia alerts system when its light curve exhibited a greater than or similar to 4 mag rise in 2018-2019. The brightening was also observable at mid-infared wavelengths. The infrared colors of Gaia 18dvy became bluer as the outburst progressed. Its optical and near-infrared spectroscopic characteristics in the outburst phase are consistent with those of bona fide FU Orionis-type young eruptive stars. The progenitor of the outburst is probably a low-mass K-type star with an optical extinction of similar to 3 mag. A radiative transfer modeling of the circumstellar structure, based on the quiescent spectral energy distribution, indicates a disk with a mass of 4 x 10(-3)M. Our simple accretion disk modeling implies that the accretion rate had been exponentially increasing for more than 3 yr until mid-2019, when it reached a peak value of 6.9 x 10(-6)M yr(-1). In many respects, Gaia 18dvy is similar to the FU Ori-type object HBC 722.