Proper Motion and Natal Kick in the Galactic Black Hole X-Ray Binary AT2019wey
Abstract Understanding the formation mechanisms of stellar-mass black hole X-ray binaries (BHXBs) remains a fundamental challenge in astrophysics. The natal kick velocities imparted during black hole (BH) formation provide crucial constraints on these formation channels. In this work, we present a new-epoch very long baseline interferometry (VLBI) observation of the Galactic BHXB AT2019wey carried out in 2023. Combining with archival VLBI data from 2020, we successfully measure the proper motion of AT2019wey over a 3 yr timescale, namely, 0.78 ± 0.12 mas yr −1 in R.A. and −0.42 ± 0.07 mas yr −1 in decl. Employing the measured proper motion, we estimate its peculiar velocity and the potential kick velocity (PKV) through Monte Carlo simulations, incorporating uncertainties of its distance and radial velocity. The estimated PKV distributions and height above the Galactic plane suggest that AT2019wey’s BH likely formed through a supernova explosion rather than direct collapse.
Authors
- Tao An (ORCID: https://orcid.org/0000-0003-4341-0029)
- M. Giroletti (ORCID: https://orcid.org/0000-0002-8657-8852)
- Lang Cui (ORCID: https://orcid.org/0000-0003-0721-5509)
- Pengfei Jiang (ORCID: https://orcid.org/0000-0003-3166-5657)
- Giulia Migliori (ORCID: https://orcid.org/0000-0003-0216-8053)
- S. Frey (ORCID: https://orcid.org/0000-0003-3079-1889)
- Ning Chang (ORCID: https://orcid.org/0000-0002-8684-7303)
- Hongmin Cao (ORCID: https://orcid.org/0000-0003-1514-881X)
- K. É. Gabányi (ORCID: https://orcid.org/0000-0003-1020-1597)
- Jun Yang (ORCID: https://orcid.org/0000-0002-2322-5232)
- Wenda Zhang (ORCID: https://orcid.org/0000-0003-1702-4917)
- Xiaoyu Hong (ORCID: https://orcid.org/0000-0002-1992-5260)
Institutions
- Eötvös Loránd University (HU)
- Shanghai Astronomical Observatory (CN)
- Xinjiang Astronomical Observatory (CN)
- Konkoly Observatory (HU)
- Istituto di Radioastronomia di Bologna (IT)
- HUN-REN Research Centre for Astronomy and Earth Sciences (HU)
- National Astronomical Observatories (CN)
- Chalmers University of Technology (SE)
- Shangqiu Normal University (CN)
- Xinjiang University (CN)
Publication Details
- Journal
- The Astrophysical Journal
- Published
- 2025-04-16
- DOI
- https://doi.org/10.3847/1538-4357/adc0f7
- Primary Topic
- Astrophysical Phenomena and Observations
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Natural Science Foundation of China
- Hungarian Scientific Research Fund
- Nemzeti Kutatási Fejlesztési és Innovációs Hivatal
- National Research, Development and Innovation Office