Serendipitous observation of a white dwarf companion to a <i>JWST</i>/MIRI coronagraphic calibrator
ABSTRACT We present the unplanned detection of a white dwarf companion to the star HD 218261 in mid-infrared (10–16 $\mu$m) observations with JWST/MIRI. This star was observed as a calibrator for coronagraphic observations of the exoplanet host HR 8799. HD 218261 B has only previously been detected by Gaia, and only in visible light. We confidently detect the companion in the mid-infrared, where it is less luminous than the primary by a factor of ${\sim} 10^4$. The visible and mid-infrared photometry are consistent with a white dwarf of $T_\text{eff}\approx 10000$ K, $M\approx 0.8~\mathrm{ M}_\odot$, though observation of its optical spectrum is required to precisely constrain its physical parameters. These results demonstrate that precise mid-infrared photometry of white dwarf companions to bright stars can be obtained with MIRI, opening up new possibilities for studying white dwarfs in close binaries.
Authors
- Mary Anne Limbach (ORCID: https://orcid.org/0000-0002-9521-9798)
- Alexander Venner (ORCID: https://orcid.org/0000-0002-8400-1646)
- Mathilde Mâlin (ORCID: https://orcid.org/0000-0002-2918-8479)
- Logan Pearce (ORCID: https://orcid.org/0000-0003-3904-7378)
- A. Boccaletti (ORCID: https://orcid.org/0000-0001-9353-2724)
- Simon Blouin (ORCID: https://orcid.org/0000-0002-9632-1436)
Institutions
- Centre National de la Recherche Scientifique (FR)
- Space Telescope Science Institute (US)
- Johns Hopkins University (US)
- Délégation Paris 7 (FR)
- University of Southern Queensland (AU)
- Université Paris Cité (FR)
- University of Victoria (CA)
- Université Paris Sciences et Lettres (FR)
- University of Michigan (US)
- Johns Hopkins Medicine (US)
- Sorbonne Université (FR)
- Sorbonne Paris Cité (FR)
- Laboratoire d’études spatiales et d’instrumentation en astrophysique (FR)
- Astronomy Australia (AU)
- University of Baltimore (US)
Publication Details
- Journal
- Monthly Notices of the Royal Astronomical Society Letters
- Published
- 2024-11-04
- DOI
- https://doi.org/10.1093/mnrasl/slae106
- Citations
- 1
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 0.33
Funders
- National Aeronautics and Space Administration
- California Institute of Technology
- University of Michigan
- Space Telescope Science Institute
- European Space Agency
- Swinburne University of Technology
- Jet Propulsion Laboratory
- University of California, Los Angeles