Properties of the Hyades, the eclipsing binary HD 27130, and the oscillating red giant <i>ϵ</i> Tauri

Brogaard, K.; Pakštienė, E.; Grundahl, F.; Mikolaitis, Š.; Tautvaišienė, G.; Slumstrup, D.; Talens, G. J. J.; VandenBerg, Don A.; Miglio, A.; Arentoft, T.; Kjeldsen, H.; Janulis, R.; Drazdauskas, A.; Marchini, Alessandro; Minkevičiūtė, R.; Stonkutė, E.; Bagdonas, V.; Andersen, M. Fredslund; Jessen-Hansen, J.; Pallé, P. L.; Dorval, Patrick; Snellen, I. A. G.; Otten, G. P. P. L.; White, T. R.

doi:10.1051/0004-6361/202039250

Cited by 9 publications

(7 citation statements)

References 78 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This has been exploited in both globular clusters (e.g., Brogaard et al 2017;Kaluzny et al 2014Kaluzny et al , 2015Thompson et al 2010Thompson et al , 2020 and open clusters (e.g., Brogaard et al 2011;Kaluzny et al 2006;Knudstrup et al 2020;Meibom et al 2009;Sandquist et al 2016;Torres et al 2020). However, sometimes the eclipsing systems found are on the main sequence, which still allows some model constraints, but not on the age (e.g., Brogaard et al 2021).…”

Section: Introductionmentioning

confidence: 99%

Age and helium content of the open cluster NGC 6791 from multiple eclipsing binary members

Brogaard

Grundahl

Sandquist

et al. 2021

A&A

Self Cite

View full text Add to dashboard Cite

Context. Models of stellar structure and evolution can be constrained using accurate measurements of the parameters of eclipsing binary members of open clusters. Multiple binary stars provide the means to tighten the constraints and, in turn, to improve the precision and accuracy of the age estimate of the host cluster. In the previous two papers of this series, we have demonstrated the use of measurements of multiple eclipsing binaries in the old open cluster NGC 6791 to set tighter constraints on the properties of stellar models than was previously possible, thereby improving both the accuracy and precision of the cluster age. Aims. We identify and measure the properties of a non-eclipsing cluster member, V56, in NGC 6791 and demonstrate how this provides additional model constraints that support and strengthen our previous findings. Methods. We analyse multi-epoch spectra of V56 from FLAMES in conjunction with the existing photometry and measurements of eclipsing binaries in NGC6971. Results. The parameters of the V56 components are found to be Mp = 1.103 ± 0.008 M⊙ and Ms = 0.974 ± 0.007 M⊙, Rp = 1.764 ± 0.099 R⊙ and Rs = 1.045 ± 0.057 R⊙, Teff,p = 5447 ± 125 K and Teff,s = 5552 ± 125 K, and surface [Fe/H] = +0.29 ± 0.06 assuming that they have the same abundance. Conclusions. The derived properties strengthen our previous best estimate of the cluster age of 8.3 ± 0.3 Gyr and the mass of stars on the lower red giant branch (RGB), which is MRGB = 1.15 ± 0.02 M⊙ for NGC 6791. These numbers therefore continue to serve as verification points for other methods of age and mass measures, such as asteroseismology.

show abstract

Section: Introductionmentioning

confidence: 99%

Age and helium content of the open cluster NGC 6791 from multiple eclipsing binary members

Brogaard

Grundahl

Sandquist

et al. 2021

A&A

Self Cite

View full text Add to dashboard Cite

show abstract

“…Several studies have found eclipsing binaries in stellar associations whose ages are known. These are the cases of M11, a ∼200 Myr old open cluster (see the case of KV29, a massive system Bavarsad et al 2016); the Hyades, which is 625-790 Myr, and several interesting systems (HD 27130, which has a solarlike primary by Brogaard et al 2021, andvA 50, a M4 plus, perhaps, a planet David et al 2016); Praesepe, which is 600-800 Myr (several M-type binaries; Gillen et al 2017); several young stellar associations such as UpperSco, 5-10 Myr (USco J161630.68-251220.1, a M 5.5 primary with a very low-mass star close to the substellar limit, Lodieu et al 2015; or the transiting brown dwarf RIK 72 b, David et al 2019), or the first ever discovered eclipsing binary brown dwarfs, which is located in the 1 Myr massive association in Orion (Stassun et al 2006); and in globular clusters, such as NGC 6362, a 11.67 Gyr association that includes V40, a solar-like pair (Kaluzny et al 2015).…”

Section: Eclipsing Brown Dwarf Inflated By Its Subgiant Hostmentioning

confidence: 99%

Uncovering the ultimate planet impostor

Lillo-Box

Ribas

Montesinos

et al. 2021

A&A

View full text Add to dashboard Cite

Context. Exoplanet searches through space-based photometric time series have shown to be very efficient in recent years. However, follow-up efforts on the detected planet candidates have been demonstrated to be critical to uncover the true nature of the transiting objects. Aims. In this paper we show a detailed analysis of one of those false positives hidden as planetary signals. In this case, the candidate KOI-3886.01 showed clear evidence of a planetary nature from various techniques. Indeed, the properties of the fake planet set it among the most interesting and promising for the study of planetary evolution as the star leaves the main sequence. Methods. To unveil the true nature of this system, we present a complete set of observational techniques including high-spatial resolution imaging, high-precision photometric time series (showing eclipses, phase curve variations, and asteroseismology signals), high-resolution spectroscopy, and derived radial velocities to unveil the true nature of this planet candidate. Results. We find that KOI-3886.01 is an interesting false positive case: a hierarchical triple system composed by a ~K2 III giant star (KOI-3886 A) accompanied by a close-in eclipsing binary formed by a subgiant ~G4 IV star (KOI-3886 B) and a brown dwarf (KOI-3886 C). In particular, KOI-3886 C is one of the most irradiated brown dwarfs known to date, showing the largest radius in this substellar regime. It is also the first eclipsing brown dwarf known around an evolved star. Conclusions. In this paper we highlight the relevance of complete sets of follow-up observations to extrasolar planets detected by the transit technique using large-pixel photometers such as Kepler and TESS and, in the future, PLATO. In particular, multi-color high-spatial resolution imaging was the first hint toward ruling out the planet scenario in this system.

show abstract

“…Several studies have found eclipsing binaries in stellar associations whose ages are known. These are the cases of M11, a ∼200 Myr old open cluster (see the case of KV29, a massive system Bavarsad et al 2016); the Hyades, which is 625-790 Myr, and several interesting systems (HD 27130, which has a solarlike primary by Brogaard et al 2021, andvA 50, a M4 plus, perhaps, a planet David et al 2016); Praesepe, which is 600-800 Myr (several M-type binaries; Gillen et al 2017); several young stellar associations such as UpperSco, 5-10 Myr (USco J161630.68-251220.1, a M5.5 primary with a very low-mass star close to the substellar limit, Lodieu et al 2015; or the transiting brown dwarf RIK 72 b, David et al 2019), or the first ever discovered eclipsing binary brown dwarfs, which is located in the 1 Myr massive association in Orion (Stassun et al 2006b); and in globular clusters, such as NGC 6362, a 11.67 Gyr association that includes V40, a solar-like pair (Kaluzny et al 2015).…”

Section: Eclipsing Brown Dwarf Inflated By Its Subgiant Hostmentioning

confidence: 99%

Uncovering the ultimate planet impostor. An eclipsing brown dwarf in a hierarchical triple with two evolved stars

Lillo-Box,

Ribas,

Montesinos

et al. 2021

Preprint

View full text Add to dashboard Cite

Context. Exoplanet searches through space-based photometric time series have shown to be very efficient in recent years. However, follow-up efforts on the detected planet candidates have been demonstrated to be critical to uncover the true nature of the transiting objects. Aims. In this paper we show a detailed analysis of one of those false positives hidden as planetary signals. In this case, the candidate KOI-3886.01 showed clear evidence of a planetary nature from various techniques. Indeed, the properties of the fake planet set it among the most interesting and promising for the study of planetary evolution as the star leaves the main sequence. Methods. To unveil the true nature of this system, we present a complete set of observational techniques including high-spatial resolution imaging, high-precision photometric time series (showing eclipses, phase curve variations, and asteroseismology signals), high-resolution spectroscopy, and derived radial velocities to unveil the true nature of this planet candidate. Results. We find that KOI-3886.01 is an interesting false positive case: a hierarchical triple system composed by a ∼K2 III giant star (KOI-3886 A) accompanied by a close-in eclipsing binary formed by a subgiant ∼G4 IV star (KOI-3886 B) and a brown dwarf (KOI-3886 C). In particular, KOI-3886 C is one of the most irradiated brown dwarfs known to date, showing the largest radius in this substellar regime. It is also the first eclipsing brown dwarf known around an evolved star. Conclusions. In this paper we highlight the relevance of complete sets of follow-up observations to extrasolar planets detected by the transit technique using large-pixel photometers such as Kepler and TESS and, in the future, PLATO. In particular, multi-color high-spatial resolution imaging was the first hint toward ruling out the planet scenario in this system.

show abstract

Properties of the Hyades, the eclipsing binary HD 27130, and the oscillating red giant ϵ Tauri

Cited by 9 publications

References 78 publications

Age and helium content of the open cluster NGC 6791 from multiple eclipsing binary members

Age and helium content of the open cluster NGC 6791 from multiple eclipsing binary members

Uncovering the ultimate planet impostor

Uncovering the ultimate planet impostor. An eclipsing brown dwarf in a hierarchical triple with two evolved stars

Contact Info

Product

Resources

About