Orbiting a binary

Bonavita, M.; D’Orazi, V.; Mesa, D.; Fontanive, C.; Desidera, S.; Messina, S.; Daemgen, S.; Gratton, R.; Vigan, A.; Bonnefoy, M.; Zurlo, A.; Antichi, J.; Avenhaus, H.; Baruffolo, A.; Baudino, J. L.; Beuzit, Jean-Luc; Boccaletti, A.; Bruno, P.; Buey, T.; Carbillet, Marcel; Cascone, E.; Chauvin, G.; Claudi, R.; Caprio, Vincenzo De; Fantinel, D.; Farisato, G.; Feldt, M.; Galicher, R.; Giro, E.; Gry, C.; Hagelberg, J.; Incorvaia, S.; Janson, Markus; Jaquet, M.; Lagrange, Anne-Marie; Langlois, M.; Lannier, J.; Coroller, H. Le; Lessio, L.; Ligi, R.; Maire, Anne-Lise; Meyer, Michael; Ménard, F.; Perrot, C.; Peretti, S.; Petit, Cyril; Ramos, J.; Roux, A.; Salasnich, Bernardo; Salter, G.; Samland, M.; Scuderi, S.; Schlieder, Joshua E.; Surez, M.; Turatto, M.; Weber, L.

doi:10.1051/0004-6361/201731003

Cited by 12 publications

(7 citation statements)

References 103 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The presence of a companion may be revealed as a difference on short-term proper motions taken at different epochs or between short-term and long-term proper motions (Bonavita et al 2017). The proper motion difference depends on companion mass, orbital separation, and orbital parameters (Makarov & Kaplan 2005).…”

Section: Appendix A: Rotation Periodmentioning

confidence: 99%

In-depth study of moderately young but extremely red, very dusty substellar companion HD 206893B

Delorme

Schmidt

Bonnefoy

et al. 2017

A&A

Self Cite

View full text Add to dashboard Cite

Context. The substellar companion HD 206893b has recently been discovered by direct imaging of its disc-bearing host star with the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) instrument. Aims. We investigate the atypical properties of the companion, which has the reddest near-infrared colours among all known substellar objects, either orbiting a star or isolated, and we provide a comprehensive characterisation of the host star-disc-companion system. Methods. We conducted a follow-up of the companion with adaptive optics imaging and spectro-imaging with SPHERE, and a multi-instrument follow-up of its host star. We obtain a R = 30 spectrum from 0.95 to 1.64 μm of the companion and additional photometry at 2.11 and 2.25 μm. We carried out extensive atmosphere model fitting for the companions and the host star in order to derive their age, mass, and metallicity. Results. We found no additional companion in the system in spite of exquisite observing conditions resulting in sensitivity to 6 MJup (2 MJup) at 0.5′′ for an age of 300 Myr (50 Myr). We detect orbital motion over more than one year and characterise the possible Keplerian orbits. We constrain the age of the system to a minimum of 50 Myr and a maximum of 700 Myr, and determine that the host-star metallicity is nearly solar. The comparison of the companion spectrum and photometry to model atmospheres indicates that the companion is an extremely dusty late L dwarf, with an intermediate gravity (log g ~ 4.5–5.0) which is compatible with the independent age estimate of the system. Conclusions. Though our best fit corresponds to a brown dwarf of 15–30 MJup aged 100–300 Myr, our analysis is also compatible with a range of masses and ages going from a 50 Myr 12 MJup planetary-mass object to a 50 MJup Hyades-age brown dwarf. Even though this companion is extremely red, we note that it is more probable that it has an intermediate gravity rather than the very low gravity that is often associated with very red L dwarfs. We also find that the detected companion cannot shape the observed outer debris disc, hinting that one or several additional planetary mass objects in the system might be necessary to explain the position of the disc inner edge.

show abstract

Section: Appendix A: Rotation Periodmentioning

confidence: 99%

In-depth study of moderately young but extremely red, very dusty substellar companion HD 206893B

Delorme

Schmidt

Bonnefoy

et al. 2017

A&A

Self Cite

View full text Add to dashboard Cite

show abstract

“…In only five more cases, it was possible to obtain a spectrum with a larger resolution (R = 350), using the SPHERE long-slit spectroscopy (LSS; Vigan et al 2008) observing mode. This has been done for 2MASS J01225093−2439505 B (Hinkley et al 2015), PZ Tel B (Maire et al 2016), HR 3549 B (Mesa et al 2016), HD 284149 B (Bonavita et al 2017), and HIP 64892 B (Cheetham et al 2018). Moreover, spectra in the NIR for companions at large separation from the host star were obtained at medium resolution with SINFONI (e.g.…”

mentioning

confidence: 99%

Characterizing brown dwarf companions with IRDIS long-slit spectroscopy: HD 1160 B and HD 19467 B

Mesa

D’Orazi

Vigan

et al. 2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

The determination of the fundamental properties (mass, separation, age, gravity, and atmospheric properties) of brown dwarf companions allows us to infer crucial informations on their formation and evolution mechanisms. Spectroscopy of substellar companions is available to date only for a limited number of objects (and mostly at very low resolution, R < 50) because of technical limitations, i.e. contrast and angular resolution. We present medium resolution (R = 350), coronagraphic long-slit spectroscopic observations with SPHERE of two substellar companions, HD 1160 B and HD 19467 B. We found that HD 1160 B has a peculiar spectrum that cannot be fitted by spectra in current spectral libraries. A good fit is possible only considering separately the Y+J and the H spectral band. The spectral type is between M5 and M7. We also estimated a Teff of 2800–2900 K and a log g of 3.5–4.0 dex. The low surface gravity seems to favour young age (10–20 Myr) and low mass (∼20 MJup ) for this object. HD 19467 B is instead a fully evolved object with a Teff of ∼1000 K and log g of ∼5.0 dex. Its spectral type is T6 ± 1.

show abstract

“…While the detection of the companion confirms the validity of our selection method, GJ3346 B is not suitable for a detailed analysis to obtain an estimate of its dynamical mass, as done for other objects showing significant ∆µ, such as HD 284149 B (Bonavita et al 2017). Given its long period and the lack of information on its inclination and eccentricity 7 , such analysis, based on the method proposed by Makarov & Kaplan (2005) could only lead to a rather unreliable estimate of its minimum mass at best (Fontanive et al, in prep., for a detailed description of the mass estimate method as well as its limitations).…”

Section: Discussionmentioning

confidence: 69%

A new white dwarf companion around the Δμ star GJ 3346

Bonavita

Fontanive

Desidera

et al. 2020

Monthly Notices of the Royal Astronomical Society

Self Cite

View full text Add to dashboard Cite

We present the discovery of a white dwarf companion at ∼ 3.6 from GJ 3346, a nearby (π ∼ 42 mas) K star observed with SPHERE@VLT as part of an open time survey for faint companions to objects with significant proper motion discrepancies (∆µ) between Gaia DR1 and Tycho-2. Syrius-like systems like GJ 3346 AB, which include a main sequence star and a white dwarf, can be difficult to detect because of the intrinsic faintness of the latter. They have, however, been found to be common contaminants for direct imaging searches. White dwarfs have in fact similar brightness to sub-stellar companions in the infrared, while being much brighter in the visible bands like those used by Gaia. Combining our observations with Gaia DR2 and with several additional archival data sets, we were able to fully constrain the physical properties of GJ 3346 B, such as its effective temperature (11×10 3 ±500 K) as well as the cooling age of the system (648±58 Myrs). This allowed us to better understand the system history and to partially explains the discrepancies previously noted in the age indicators for this objects. Although further investigation is still needed, it seems that GJ 3346, which was previously classified as young, is in fact most likely to be older than 4 Gyrs. Finally, given that the mass (0.58 ± 0.01 M ) and separation (85 au) of GJ 3346 B are compatible with the observed ∆µ, this discovery represents a further confirmation of the potential of this kind of dynamical signatures as selection methods for direct imaging surveys targeting faint, sub-stellar companions.

show abstract

Orbiting a binary

Cited by 12 publications

References 103 publications

In-depth study of moderately young but extremely red, very dusty substellar companion HD 206893B

In-depth study of moderately young but extremely red, very dusty substellar companion HD 206893B

Characterizing brown dwarf companions with IRDIS long-slit spectroscopy: HD 1160 B and HD 19467 B

A new white dwarf companion around the Δμ star GJ 3346

Contact Info

Product

Resources

About