J/MNRAS/472/2517 Stellar twins in RAVE with Gaia (Jofre+, 2017)
Climbing the cosmic ladder with stellar twins in RAVE with Gaia.
Jofre P., Traven G., Hawkins K., Gilmore G., Sanders J.L., Madler T.,
Steinmetz M., Kunder A., Kordopatis G., McMillan P., Bienayme O.,
Bland-Hawthorn J., Gibson B.K., Grebel E.K., Munari U., Navarro J.,
Parker Q., Reid W., Seabroke G., Zwitter T.
<Mon. Not. R. Astron. Soc., 472, 2517-2533 (2017)>
=2017MNRAS.472.2517J 2017MNRAS.472.2517J (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Stars, double and multiple ;
Parallaxes, trigonometric
Keywords: methods: statistical - techniques: spectroscopic - stars: distances
Abstract:
We apply the twin method to determine parallaxes to 232 545 stars of
the RAVE survey using the parallaxes of Gaia DR1 as a reference. To
search for twins in this large data set, we apply the t-student
stochastic neighbour embedding projection that distributes the data
according to their spectral morphology on a two-dimensional map. From
this map, we choose the twin candidates for which we calculate a
χ2 to select the best sets of twins. Our results show a
competitive performance when compared to other model-dependent methods
relying on stellar parameters and isochrones. The power of the method
is shown by finding that the accuracy of our results is not
significantly affected if the stars are normal or peculiar since the
method is model free. We find twins for 60 per cent of the RAVE sample
that are not contained in Tycho-Gaia Astrometric Solution (TGAS) or
that have TGAS uncertainties that are larger than 20 per cent. We
could determine parallaxes with typical errors of 28 per cent. We
provide a complementary data set for the RAVE stars not covered by
TGAS, or that have TGAS uncertainties which are larger than 20 per
cent, with model-free parallaxes scaled to the Gaia measurements.
Description:
The twin method is applied to determine parallaxes for stars in the
RAVE survey. The method is based on the proposition that if two stars
have the same spectra (hence twins) they have the same luminosity. By
knowing the parallax of one star, we can estimate the parallax of its
twin by comparing their magnitudes.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 58 79 Parallaxes obtained for individual members in
each cluster analysed in this work
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
III/279 : RAVE 5th data release (Kunder+, 2017)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Cluster Cluster name
12- 32 A21 --- RAVE RAVE star name
33- 41 F9.6 mas plxtwin Mean twin parallax
44- 52 F9.7 mas s_plxtwin Standard deviation of plxtwin
56- 58 I3 --- Ntwin Number of twin candidates
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 26-Jun-2020