Lennart Lindegren
Professor
A noninteracting low-mass black hole–giant star binary system
Author
Summary, in English
Black hole binary systems with companion stars are typically found via their x-ray emission, generated by interaction and accretion. Noninteracting binaries are expected to be plentiful in the Galaxy but must be observed using other methods. We combine radial velocity and photometric variability data to show that the bright, rapidly rotating giant star 2MASS J05215658+4359220 is in a binary system with a massive unseen companion. The system has an orbital period of ~83 days and near-zero eccentricity. The photometric variability period of the giant is consistent with the orbital period, indicating star spots and tidal synchronization. Constraints on the giant’s mass and radius imply that the unseen companion is 3:3þ - 2 0 : : 8 7 solar masses, indicating that it is a noninteracting low-mass black hole or an unexpectedly massive neutron star.
Department/s
- Lund Observatory - Undergoing reorganization
Publishing year
2019
Language
English
Pages
637-640
Publication/Series
Science
Volume
366
Issue
6465
Document type
Journal article
Publisher
American Association for the Advancement of Science (AAAS)
Topic
- Astronomy, Astrophysics and Cosmology
Status
Published
ISBN/ISSN/Other
- ISSN: 0036-8075