A long-lived compact jet in the black hole X-ray binary candidate AT2019wey
Journal article, 2022

AT2019wey is a transient discovered by the Asteroid Terrestrial-impact Last Alert System survey in December of 2019. Follow-up optical, radio, and X-ray observations led to classification of this source as a Galactic black hole X-ray binary candidate. We carried out one-epoch 6.7 GHz European Very Long Baseline Interferometry Network and two-epoch multi-frequency (1.6, 4.5, 6.7 GHz) Very Long Baseline Array observations within a year after its discovery. These observations reveal a fading and flat-spectrum radio source with no discernible motion. These features suggest the detection of a compact jet. The source appears resolved at milliarcsecond scales, and the source angular size versus frequency trend is consistent with scatter broadening. This allows us to constrain the lower limit of the source distance to 6 kpc if the scattering medium is in a Galactic spiral arm. For a source location at greater than 3 kpc, the estimated upper limit of the peculiar velocity suggests the asymmetric natal kick may have occurred during the black hole formation stage.

Stars: individual: AT2019wey

X-rays: binaries

ISM: jets and outflows

Author

Hong Min Cao

Shangqiu Normal University

Giulia Migliori

Istituto di Radioastronomia

M. Giroletti

Istituto di Radioastronomia

Sándor Frey

Eötvös Loránd University (ELTE)

Hungarian Academy of Sciences

Jun Yang

Chalmers, Space, Earth and Environment, Onsala Space Observatory

Krisztina E. Gabányi

Hungarian Academy of Sciences

Eötvös Loránd University (ELTE)

Lang Cui

Chinese Academy of Sciences

T. An

Shanghai Astronomical Observatory

X. Y. Hong

Shanghai Astronomical Observatory

Wen Da Zhang

Chinese Academy of Sciences

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 657 A104

Subject Categories

Meteorology and Atmospheric Sciences

Astronomy, Astrophysics and Cosmology

Geophysics

DOI

10.1051/0004-6361/202142241

More information

Latest update

2/3/2022 1