Direct imaging and dynamical mass of a benchmark T-type brown dwarf companion to HD 167665

Context . A low-mass companion potentially in the brown dwarf mass regime was discovered on a ~12 yr orbit (~5.5 au) around HD 167665 using radial velocity (RV) monitoring. Joint RV–astrometry analyses confirmed that HD 167665B is a brown dwarf with precisions on the measured mass of ~4–9%. Brown dwarf companions with measured mass and luminosity are valuable for testing formation and evolutionary models. However, its atmospheric properties and luminosity are still unconstrained, preventing detailed tests of evolutionary models. Aims . We further characterize the HD 167665 system by measuring the luminosity and refining the mass of its companion and reassessing the stellar age. Methods . We present new high-contrast imaging data of the star and of its close-in environment from SPHERE and GRAVITY, which we combined with RV data from CORALIE and HIRES and astrometry from H IPPARCOS and Gaia . Results . The analysis of the host star properties indicates an age of 6.20 ± 1.13 Gyr. GRAVITY reveals a point source near the position predicted from a joint fit of RV data and H IPPARCOS – Gaia proper motion anomalies. Subsequent SPHERE imaging confirms the detection and reveals a faint point source of contrast of ∆ H2 = 10.95 ± 0.33 mag at a projected angular separation of ~180 mas. A joint fit of the high-contrast imaging, RV, and H IPPARCOS intermediate astrometric data together with the Gaia astrometric parameters constrains the mass of HD 167665B to ~1.2%, 60.3 ± 0.7 M J . The SPHERE colors and spectrum point to an early or mid-T brown dwarf of spectral type T4 −2 +1 . Fitting the SPHERE spectrophotometry and GRAVITY spectrum with synthetic spectra suggests an effective temperature of ~1000–1150 K, a surface gravity of ~5.0–5.4 dex, and a bolometric luminosity log( L / L ⊙ )=−4.892 −0.028 +0.024 dex. The mass, luminosity, and age of the companion can only be reproduced within 3 σ by the hybrid cloudy evolutionary models of Saumon & Marley (2008, ApJ, 689, 1327), whereas cloudless evolutionary models underpredict its luminosity.

Authors

Institutions

Publication Details

Journal
Astronomy and Astrophysics
Published
2024-09-27
DOI
https://doi.org/10.1051/0004-6361/202451184
Citations
2
Primary Topic
Stellar, planetary, and galactic studies
Type
article
Field-Weighted Citation Impact
0.66

Funders

Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

Direct imaging and dynamical mass of a benchmark T-type brown dwarf companion to HD 167665

É. Gendron, Jens Kammerer, M. Bonnefoy, M. Janson et al.
2 citations
Astronomy and Astrophysics
Stellar, planetary, and galactic studies
0.66
article

Direct imaging and dynamical mass of a benchmark T-type brown dwarf companion to HD 167665

É. Gendron, Jens Kammerer, M. Bonnefoy, M. Janson, Markus R. Meyer, C. Straubmeier, S. Lacour, Sasha Hinkley, John D. Monnier, P. Delorme, V. Lapeyrère, E. Wieprecht, C. Paladini, M. Houllé, Élodie Choquet, J. Hagelberg, V. D’Orazi, S. Hippler, A. Drescher, S. Gillessen, William O. Balmer, A. Cridland, Jean-Philippe Berger, T. Ott, A. Eckart, F. Cantalloube, F. Vincent, P. Caselli, E. Matthews, D. Mesa, C. Babusiaux, M. A. Nowak, M. Bonavita, L. Kreidberg, Laurent Pueyo, E. Rickman, N. Pourré, D. Ségransan, R. Abuter, T. Paumard, M. Langlois, Beth Biller, T. Stolker, J. Stadler, J.-L. Beuzit, G. Heißel, G. Bourdarot, Sarah Blunt, E. F. van Dishoeck, C. Lazzoni, J. H. Girard, A. Mérand, D. Lutz, S. Messina, K. Perraut, A. Leclerc, Jason Dexter, Zafar Rustamkulov, M. Benisty, M. Samland, S. Desidera, F. Widmann, Thomas Shimizu, G. P. P. L. Otten, Valentin Christiaens, Ş. Yazıcı, A. Amorim, C. Perrot, E. Nasedkin, J. Shangguan, L. J. Tacconi, B. Charnay, O. Straub, A. Zurlo, R. Gratton, G. Chauvin, P. Mollière, P. Kervella, J.-B. Le Bouquin, David K. Sing, V. Squicciarini, Z. Wahhaj, G. Duvert, W. Brandner, F. Eisenhauer, R. Dembet, A. Boccaletti, P. García, S. D. von Fellenberg, S. Udry, A. Vigan, R. García López, Jason Wang, J. Woillez, A.-M. Lagrange, R. Genzel, A.-L. Maire, D. Mouillet, R. Galicher, G. Perrin, O. Pfuhl, G. Rousset, P. Léna, E. Sturm, L. Jocou, X. Haubois, V. Coudé du Foresto, Z. Hubert, Th. Henning, Y. Clénet, F. Gao, H. Bonnet, F. Ménard
article en
2 citations

Abstract

Context . A low-mass companion potentially in the brown dwarf mass regime was discovered on a ~12 yr orbit (~5.5 au) around HD 167665 using radial velocity (RV) monitoring. Joint RV–astrometry analyses confirmed that HD 167665B is a brown dwarf with precisions on the measured mass of ~4–9%. Brown dwarf companions with measured mass and luminosity are valuable for testing formation and evolutionary models. However, its atmospheric properties and luminosity are still unconstrained, preventing detailed tests of evolutionary models. Aims . We further characterize the HD 167665 system by measuring the luminosity and refining the mass of its companion and reassessing the stellar age. Methods . We present new high-contrast imaging data of the star and of its close-in environment from SPHERE and GRAVITY, which we combined with RV data from CORALIE and HIRES and astrometry from H IPPARCOS and Gaia . Results . The analysis of the host star properties indicates an age of 6.20 ± 1.13 Gyr. GRAVITY reveals a point source near the position predicted from a joint fit of RV data and H IPPARCOS – Gaia proper motion anomalies. Subsequent SPHERE imaging confirms the detection and reveals a faint point source of contrast of ∆ H2 = 10.95 ± 0.33 mag at a projected angular separation of ~180 mas. A joint fit of the high-contrast imaging, RV, and H IPPARCOS intermediate astrometric data together with the Gaia astrometric parameters constrains the mass of HD 167665B to ~1.2%, 60.3 ± 0.7 M J . The SPHERE colors and spectrum point to an early or mid-T brown dwarf of spectral type T4 −2 +1 . Fitting the SPHERE spectrophotometry and GRAVITY spectrum with synthetic spectra suggests an effective temperature of ~1000–1150 K, a surface gravity of ~5.0–5.4 dex, and a bolometric luminosity log( L / L ⊙ )=−4.892 −0.028 +0.024 dex. The mass, luminosity, and age of the companion can only be reproduced within 3 σ by the hybrid cloudy evolutionary models of Saumon & Marley (2008, ApJ, 689, 1327), whereas cloudless evolutionary models underpredict its luminosity.

Astronomy and AstrophysicsVol. 691
Université Claude Bernard Lyon 1 (FR), University College Dublin (IE), Northwestern University (US), École Normale Supérieure de Lyon (FR), University of Geneva (CH), Leiden University (NL), California Institute of Technology (US), Centre National de la Recherche Scientifique (FR), Space Telescope Science Institute (US), Institute of Astronomy and Astrophysics, Academia Sinica (TW), European Southern Observatory (DE), Joint Institute for Laboratory Astrophysics (US), University of Lisbon (PT), Johns Hopkins University (US), University of Liège (BE), Universität Hamburg (DE), Stockholm University (SE), University of Cologne (DE), Universidade do Porto (PT), Université Paris Cité (FR), Aix-Marseille Université (FR), University of Exeter (GB), University of Cambridge (GB), Université Paris Sciences et Lettres (FR), University of Michigan (US), Observatoire de Paris (FR), European Space Agency (FR), Sorbonne Université (FR), Centre de Recherche Astrophysique de Lyon (FR), Institute of Astrophysics and Space Sciences (PT), Max Planck Institute for Extraterrestrial Physics (DE), Excellence Cluster Origins (DE), Max Planck Institute for Astrophysics (DE), Royal Observatory (GB), Max Planck Institute for Astronomy (DE), Laboratoire d’études spatiales et d’instrumentation en astrophysique (FR), Osservatorio Astrofisico di Catania (IT), European Southern Observatory (CL), AlbaNova (SE), Max Planck Institute for Radio Astronomy (DE), Osservatorio Astronomico di Padova (IT), European Space Research and Technology Centre (NL), University of Chile (CL), Université Grenoble Alpes (FR), Universidad Diego Portales (CL), University of California, Berkeley (US), University of Edinburgh (GB)
National Science Foundation, National Aeronautics and Space Administration, European Space Agency, European Commission, Deutsche Forschungsgemeinschaft, Agence Nationale de la Recherche, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Eidgenössische Technische Hochschule Zürich, Centre National de la Recherche Scientifique, Université de Genève, Agencia Nacional de Investigación y Desarrollo, Max-Planck-Institut für Astronomie, Observatoire de Paris, Université de Recherche Paris Sciences et Lettres, HORIZON EUROPE Framework Programme, Office National d'études et de Recherches Aérospatiales, HORIZON EUROPE European Research Council
Openalex Percentile: Top 28%
Stellar, planetary, and galactic studies
0.66
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.