209 citations · 2.5k across the 37 of their papers we have counts for
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Benchmarking Gaia DR3 Apsis with the Hyades and Pleiades open clusters
Wolfgang Brandner, Per Calissendorff, Taisiya Kopytova
The Gaia astrophysical parameters inference system (Apsis) provides astrophysical parameter estimates for several to 100s of millions of stars. We aim to benchmark Gaia DR3 Apsis.…
Astrophysical properties of 600 bonafide single stars in the Hyades open cluster
Wolfgang Brandner, Per Calissendorff, Taisiya Kopytova
The determination of the astrophysical properties of stars remains challenging, and frequently relies on the application of stellar models. Stellar sequences in nearby open cluster…
Benchmarking MESA isochrones against the Hyades single star sequence
Wolfgang Brandner, Per Calissendorff, Taisiya Kopytova
Based on GAIA EDR3, we revisit and update our sample of bonafide single stars in the Hyades open cluster. The small observational uncertainties in parallax and photometry of EDR3 r…
SPHERE dynamical and spectroscopic characterization of HD142527B
R. Claudi, A. -L. Maire, D. Mesa +50
We detect the accreting low-mass companion HD142527B at a separation of 73 mas (11.4 au) from the star. No other companions with mass greater than 10 MJ are visible in the field of…
A Search for Variability in Exoplanet Analogues and Low-Gravity Brown Dwarfs
Johanna M. Vos, Beth A. Biller, Mariangela Bonavita +18
We report the results of a -band survey for photometric variability in a sample of young, low-gravity objects using the New Technology Telescope (NTT) and the United Kingdom Inf…
K2 Rotation Periods for low-mass Hyads and the Implications for Gyrochronology
S. T. Douglas, M. A. Agüeros, K. R. Covey +5
As the closest open cluster to the Sun, the Hyades is an important benchmark for many stellar properties, but its members are also scattered widely over the sky. Previous studies o…
Single stars in the Hyades open cluster. Fiducial sequence for testing stellar and atmospheric models
Taisiya G. Kopytova, Wolfgang Brandner, Emanuele Tognelli +4
Age and mass determinations for isolated stellar objects remain model-dependent. While stellar interior and atmospheric theoretical models are rapidly evolving, we need a powerful…
Deep -band observations of the coolest Y dwarf
Taisiya G. Kopytova, Ian J. M. Crossfield, Niall R. Deacon +7
WISE J085510.83-071442.5 (hereafter, WISE 0855-07) is the coolest Y dwarf known to date and is located at a distance of 2.31 pc, giving it the fourth largest parallax of…
Calibration of stellar and atmospheric models using the Hyades
Taisiya G. Kopytova, Wolfgang Brandner, Siegfried Röser +2
Calibration and benchmarking of evolutionary and atmospheric models is essential for the study of low-mass stars and brown dwarfs, as for isolated objects these models are the only…
Weather on the Nearest Brown Dwarfs: Resolved Simultaneous Multi-Wavelength Variability Monitoring of WISE J104915.57-531906.1AB
Beth A. Biller, Ian J. M. Crossfield, Luigi Mancini +15
We present two epochs of MPG/ESO 2.2m GROND simultaneous 6-band () photometric monitoring of the closest known L/T transition brown dwarf binary WISE J104915.57-531906.1…
Discovery of an outflow of the very low-mass star ISO 143
V. Joergens, T. Kopytova, A. Pohl
We discover that the very young very low-mass star ISO143 (M5) is driving an outflow based on spectro-astrometry of forbidden [SII] emission lines at 6716A and 6731A observed in UV…