An HST survey of photometry and multiplicity of brown dwarfs and planetary-mass objects in the field of Taurus
Abstract We present a photometric and multiplicity survey of 26 young objects with masses between 6 MJ and 37 MJ and spectral type later than M8 in the Taurus star-forming region with the Hubble Space Telescope. We search for companion candidates using two methods: a dedicated photometric technique based on the combination of colours from multi-band photometry and point spread function fitting. No companion candidates are detected beyond 30 au. With an updated membership and age identification, we determine luminosity, temperature, and mass for the 26 young objects using evolutionary models. We demonstrate that our HST observations are sensitive to companions down to masses of 1 MJ and even lower for some targets by artificial star injection tests. After survey completeness correction, we derive a binary frequency <6.5% for this sample in the 68% confidence interval for companions with mass ratios between 0.1 and 1 and separations between 30 and 7,000 au. We find no significant difference in binary frequency among planetary-mass objects in Taurus, Upper Scorpius, and the field. These findings support that the binary frequency of planetary-mass objects is settled at young ages, probably younger than 1–10 Myr, suggesting that the formation of wide-orbit planetary-mass binaries is inefficient and the disruption of them likely occurs at a very early stage in a low density environment.
Authors
- Matthew De Furio (ORCID: https://orcid.org/0000-0003-1863-4960)
- Jessy Jose (ORCID: https://orcid.org/0000-0003-4908-4404)
- Belinda Damian (ORCID: https://orcid.org/0000-0002-2234-4678)
- Sophie Dubber (ORCID: https://orcid.org/0000-0001-6951-469X)
- Beth A. Biller (ORCID: https://orcid.org/0000-0003-4614-7035)
- Loïc Albert (ORCID: https://orcid.org/0000-0003-0475-9375)
- C. Fontanive (ORCID: https://orcid.org/0000-0002-2428-9932)
- Bhavana Lalchand (ORCID: https://orcid.org/0000-0003-1618-2921)
- L. R. Bedin (ORCID: https://orcid.org/0000-0003-4080-6466)
- M. Scalco (ORCID: https://orcid.org/0000-0001-8834-3734)
- Zhoujian Zhang
- Pengyu Liu (ORCID: https://orcid.org/0000-0001-7047-0874)
- Wen-Ping Chen
- Michael C. Liu
Institutions
- University of Hawaiʻi at Mānoa (US)
- Leiden University (NL)
- University of Hawaii System (US)
- University of St Andrews (GB)
- National Central University (TW)
- Yunnan Observatories (CN)
- Westlake University (CN)
- Royal Observatory (GB)
- Indiana University Bloomington (US)
- Indian Institute of Science Education and Research, Tirupati (IN)
- Osservatorio Astronomico di Padova (IT)
- Leiden Observatory (NL)
- University of Rochester (US)
- Indiana University (US)
- Université de Montréal (CA)
- The University of Texas at Austin (US)
- National Institute for Astrophysics (IT)
- University of Edinburgh (GB)
Publication Details
- Journal
- Monthly Notices of the Royal Astronomical Society
- Published
- 2026-10-28
- DOI
- https://doi.org/10.1093/mnras/stag2058
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- National Aeronautics and Space Administration
- Space Telescope Science Institute