The first massive compact companion in a wide orbit around a hot subdwarf star

Geier S, Dorsch M, Dawson H, Pelisoli I, Munday J, Marsh TR, Schaffenroth V, Heber U (2023)

Publication Type: Journal article

Publication year: 2023

Journal

Astronomy & Astrophysics EDP Sciences

Book Volume: 677

Article Number: A11

DOI: 10.1051/0004-6361/202346407

Abstract

We report the discovery of the first hot subdwarf B (sdB) star with a massive compact companion in a wide (P = 892.5 ± 60.2 d) binary system. It was discovered based on an astrometric binary solution provided by the Gaia mission Data Release 3. We performed detailed analyses of the spectral energy distribution (SED) as well as spectroscopic follow-up observations and confirm the nature of the visible component as a sdB star. The companion is invisible despite of its high mass of Mcomp = 1.50- 0.45+0.37 M·. A main sequence star of this mass would significantly contribute to the SED and can be excluded. The companion must be a compact object, either a massive white dwarf or a neutron star. Stable Roche lobe overflow to the companion likely led to the stripping of a red giant and the formation of the sdB, the hot and exposed helium core of the giant. Based on very preliminary data, we estimate that ∼9% of the sdBs might be formed through this new channel. This binary might also be the prototype for a new progenitor class of supernovae type Ia, which has been predicted by theory.

Authors with CRIS profile

Ulrich Heber Professur für Astronomie und Astrophysik

Involved external institutions

Universität Potsdam DE Germany (DE)

How to cite

APA:

Geier, S., Dorsch, M., Dawson, H., Pelisoli, I., Munday, J., Marsh, T.R.,... Heber, U. (2023). The first massive compact companion in a wide orbit around a hot subdwarf star. Astronomy & Astrophysics, 677. https://dx.doi.org/10.1051/0004-6361/202346407

MLA:

Geier, S., et al. "The first massive compact companion in a wide orbit around a hot subdwarf star." Astronomy & Astrophysics 677 (2023).

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