Recurrent strong outbursts of an EXor-like young eruptive star Gaia20eae

Abstract

We present follow-up photometric and spectroscopic observations, and subsequent analysis of Gaia20eae. This source triggered photometric alerts during 2020 after showing a ∼3 mag increase in its brightness. Its Gaia Alert light curve showed the shape of a typical eruptive young star. We carried out observations to confirm Gaia20eae as an eruptive young star and classify it. Its pre-outburst spectral energy distribution shows that Gaia20eae is a moderately embedded Class II object with Lbol = 7.22 L⊙. The color–color and color–magnitude diagrams indicate that the evolution in the light curve is mostly gray. Multiple epochs of the Hα line profile suggest an evolution of the accretion rate and winds. The near-infrared spectra display several emission lines, a feature typical of EX Lupi- type (EXor) eruptive young stars. We estimated the mass accretion rate during the dimming phase to be M = 3–8 × 10−7 M⊙ yr−1, higher than typical T Tauri stars of similar mass and comparable to other EXors. We conclude Gaia20eae is a new EXor-type candidate.