A Candidate Giant Planet Companion to the Massive, Young White Dwarf GALEX J071816.4+373139 Informs the Occurrence of Giant Planets Orbiting B Stars
-
1.
Institute for Advanced Study
-
2.
Johns Hopkins University
-
3.
Institute of Science and Technology Austria
-
4.
California Institute of Technology
Abstract
It has been suggested that giant planet occurrence peaks for stars with M* ≈ 3 M⊙ at a value a factor of 4 higher than observed for solar-mass stars. This population of giant planets predicted to frequently orbit main-sequence B stars at a ≈ 10 au is difficult to characterize during the few hundred million years while fusion persists in their host stars. By the time those stars become massive, young white dwarfs, any giant planets present would still be luminous as a consequence of their recent formation. From an initial sample of 2195 Gaia-identified massive, young white dwarfs, we use homogeneous Spitzer Infrared Array Camera (IRAC) photometry to search for evidence of unresolved giant planets. For 30 systems, these IRAC data provide sensitivity to objects with M ≲ 10 MJup, and we identify one candidate with M ≈ 4 MJup orbiting the white dwarf GALEX J071816.4+373139. Correcting for the possibility that some of the white dwarfs in our sample result from mergers, we find a giant planet occurrence ηGP = 0.11^(+0.13)_(-0.07) for stars with initial masses M* ≳ 3 M⊙. Our occurrence inference is consistent with both the Doppler-inferred occurrence of giant planets orbiting M* ≈ 2 M⊙ giant stars and the theoretically predicted factor of 4 enhancement in the occurrence of giant planets orbiting M* ≈ 3 M⊙ stars relative to solar-mass stars. Future James Webb Space Telescope NIRCam observations of our sample would provide sensitivity to Saturn-mass planets and thereby a definitive estimate of the occurrence of giant planets orbiting stars with M* ≳ 3 M⊙.
Copyright and License
© 2025. The Author(s). Published by the American Astronomical Society.
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Acknowledgement
We thank Jay Farihi, Guangwei Fu, J. J. Hermes, Mary Anne Limbach, and Daniel Thorngren for useful discussions. S.C. thanks Siyu Yao for her constant inspiration and encouragement. S.C. acknowledges the support of the Martin A. and Helen Chooljian Member Fund, funding from the Zurich Insurance Company, and the Fund for Natural Sciences at the Institute for Advanced Study. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC; https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This research has made use of NASA's Astrophysics Data System.
Facilities
ADS - , ESO:VISTA - European Southern Observatory's 4.1 meter Visible and Infrared Survey Telescope for Astronomy, Exoplanet Archive - , Gaia - , IRSA - , NEOWISE - , Spitzer - Spitzer Space Telescope satellite, UKIRT - United Kingdom Infrared Telescope, WISE - Wide-field Infrared Survey Explorer.
Software References
astropy (Astropy Collaboration et al. 2013, 2018, 2022), numpy (C. R. Harris et al. 2020), matplotlib (J. D. Hunter 2007), R (R Core Team 2024), SciPy (P. Virtanen et al. 2020).
Files
Cheng_2025_AJ_170_47.pdf
Files
(931.2 kB)
| Name | Size | Download all |
|---|---|---|
|
md5:144b0e46aa3dff0cdf8c6ee7d4fe2fe4
|
931.2 kB | Preview Download |
Additional details
Related works
- Is new version of
- Discussion Paper: arXiv:2408.03985 (arXiv)
Funding
- Institute for Advanced Study
- National Aeronautics and Space Administration
Dates
- Accepted
-
2025-05-23
- Available
-
2025-06-24Published