J/MNRAS/469/401 Known LT dwarfs in the Gaia DR1 (Smart+, 2017)
The Gaia ultracool dwarf sample.
I. Known L and T dwarfs and the first Gaia data release.
Smart R.L., Marocco F., Caballero J.A., Jones H.R.A., Barrado D.,
Beamin J.C., Pinfield D.J., Sarro L.M.
<Mon. Not. R. Astron. Soc., 469, 401-415 (2017)>
=2017MNRAS.469..401S 2017MNRAS.469..401S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, late-type ; Proper motions ;
Photometry, infrared ; Stars, distances
Keywords: binaries: visual - brown dwarfs -
Hertzsprung-Russell and colour-magnitude diagrams - stars: late-type -
solar neighbourhood
Abstract:
We identify and investigate known ultracool stars and brown dwarfs
that are being observed or indirectly constrained by the Gaia mission.
These objects will be the core of the Gaia ultracool dwarf sample
composed of all dwarfs later than M7 that Gaia will provide direct or
indirect information on. We match known L and T dwarfs to the Gaia
first data release, the Two Micron All Sky Survey and the Wide-field
Infrared Survey Explorer AllWISE survey and examine the Gaia and
infrared colours, along with proper motions, to improve spectral
typing, identify outliers and find mismatches. There are 321 L and T
dwarfs observed directly in the Gaia first data release, of which 10
are later than L7. This represents 45 per cent of all the known LT
dwarfs with estimated GaiaG magnitudes brighter than 20.3mag. We
determine proper motions for the 321 objects from Gaia and the Two
Micron All Sky Survey positions. Combining the Gaia and infrared
magnitudes provides useful diagnostic diagrams for the determination
of L and T dwarf physical parameters. We then search the Tycho-Gaia
astrometric solution, Gaia first data release subset, to find any
objects with common proper motions to known L and T dwarfs and a high
probability of being related. We find 15 new candidate common proper
motion systems.
Description:
table2.dat: an input catalogue of known L, T and Y dwarfs. This list
began with the online census being kept by J. Gagne
(https://jgagneastro.wordpress.com/list-of-ultracool-dwarfs) which
included objects from the Dwarfarchives
(https://www.dwarfarchives.edu), the work of Dupuy et al.
(2012ApJS..201...19D 2012ApJS..201...19D), and the PhD thesis catalogue of Mace
(2014yCat.5144....0M 2014yCat.5144....0M). To this compilation, we added the objects in
Marocco (2015MNRAS.449.3651M 2015MNRAS.449.3651M) and Faherty (2016ApJS..225...10F 2016ApJS..225...10F). This
list was used to search for know L/T dwarfs in the GAia DR1 and then
also for common binary systems in the TGAS catalog.
table4.dat: The catalogue of known LT dwarfs matched to Gaia DR1
entries. Proper motions were calculated from Gaia DR1 and 2MASS
positions.
table5.dat: The catalogue of candidate CPM systems with known LT
dwarfs and the Gaia DR1 TGAS subsection.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 271 1886 The Gaia Ultracool Dwarf sample (GUCDS)
input catalogue
table3.dat 104 7 Input catalogue objects with mismatches in Gaia DR1
table4.dat 405 321 Parameters for the GUCDS-DR1 catalogue
table5.dat 200 15 Parameters for the GUCDS-DR1 catalogue
table6.dat 469 7 Probable late M dwarfs identified in the
colour-colour and colour-spectral type diagrams
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See also:
I/337 : Gaia DR1 (Gaia, 2016)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 A14 --- SName Short name used in text of paper
16- 45 A30 --- OName Longer name from discovery paper
47- 87 A41 --- DISCref Discovery paper reference BibCode (upto 2)
89-101 F13.8 deg RAdeg Right ascension (Equinox J2000)
103-115 F13.8 deg DEdeg Declination (Equinox J2000)
117-133 A17 --- SpType Spectral type
135-153 A19 --- r_SpType Spectral type reference BibCode (1)
155 I1 --- n_SpType [1/3] How Spectral type obtained (2)
157-165 F9.2 mas/yr pmRA ?=-99999 Proper motion in Rigth ascension
167-175 F9.2 mas/yr e_pmRA ?=-99999 Error in proper motion in RA
177-185 F9.2 mas/yr pmDE ?=-99999 Proper motion in declination
187-195 F9.2 mas/yr e_pmDE ?=-99999 Error in proper motion in Dec
197-215 A19 --- r_pm Proper motion reference BibCode (3)
217-226 F10.3 mag Jmag ?=-99999 J magnitude
228-237 F10.3 mag e_Jmag ?=-99999 Error in J magnitude
239 I1 --- Jtype [0/2] System of J magnitude (4)
241-259 A19 --- r_Jmag J magnitude reference
261-271 F11.4 --- Epoch ?=-99999 Epoch of position
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Note (1): The SpT_ref is sometimes set to MAROCCOetal2017 for objects that
have spectral types that are in a paper submitted but not yet published.
Note (2): How Spectral type obtained code as follows:
1 = Spectral type from optical spectra
2 = Spectral type from Near Infrared spectra
3 = Spectral type from photometry
Note (3): The r_pm is set to PMFROM2MASS--WISE when the input proper motion
was found from the difference of the 2MASS and WISE survey positions.
Note (4): System of J magnitude as follows:
1 = 2MASS system
2 = MKO system
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 26 A26 --- Name Name
28 I1 --- r_Name [1/6] Discovery references (1)
30- 48 I19 --- GaiaDR1 Gaia DR1 Source ID
50- 53 F4.1 mag DGmag Difference between Gaia DR1 G magnitude and
estimated G magnitude, G-Gest
55-104 A50 --- Rem Remarks
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Note (1): Discovery references as follows:
1 = Kirkpatrick et al. (2011, Cat. J/ApJS/197/19)
2 = Lodieu et al. (2007MNRAS.379.1423L 2007MNRAS.379.1423L)
3 = Lodieu et al. (2009A&A...505.1115L 2009A&A...505.1115L)
4 = Mace et al. (2013ApJ...777...36M 2013ApJ...777...36M)
5 = Folkes et al. (2012, Cat. J/MNRAS/427/3280)
6 = Thompson et al. (2013, Cat. J/PASP/125/809)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- SName Short name used in text of paper
17- 29 F13.9 deg RAdeg Right ascension (equinox J2000 epoch 2015)
34- 46 F13.9 deg DEdeg Declination (equinox J2000 epoch 2015)
48- 59 F12.5 mas/yr pmRA* Proper motion in RA from Gaia + 2MASS
positions, pmRA*cosDE
61- 72 F12.5 mas/yr e_pmRA* Error in proper motion in RA, e_cosDE
74- 85 F12.5 mas/yr pmDE Proper motion in Dec from Gaia + 2MASS
positions
87- 98 F12.5 mas/yr e_pmDE Error in proper motion in DE
100-111 F12.5 mag Gmag Gaia G band magnitude
113-124 F12.5 mag e_Gmag Error in Gaia G band magnitude (1)
126-130 I5 --- Nobs Number of Observations in Gaia DR1
134-152 I19 --- SourceID Gaia Source ID
154-158 F5.2 mag GmagGpred Gaia G magnitude minus predicted magnitude
160-161 I2 --- Nin3arcsec Number of matches within 3 arcseconds
in Gaia DR1
163-164 I2 --- pmflag Flag to show pm differ (2)
166-191 A26 --- OName Longer name from discovery paper
193-211 A19 --- DISCref Reference bibCode for discovery (3)
213-222 A10 --- SpTypeO Spectral type in optical
224-242 A19 --- r_SpTypeO Reference BibCode for SpTypeO
244-253 A10 --- SpTypeN Spectral type in Near infrared
255-273 A19 --- r_SpTypeN Reference BibCode for SpTypeN (3)
275-284 F10.3 mag Jmag 2MASS J band magnitude
286-295 F10.3 mag e_Jmag 2MASS J band magnitude error
297-306 F10.3 mag Hmag 2MASS H band magnitude
308-317 F10.3 mag e_Hmag 2MASS H band magnitude error
319-328 F10.3 mag Kmag 2MASS K band magnitude
330-339 F10.3 mag e_Kmag 2MASS K band magnitude error
341-350 F10.3 mag W1mag ?=-99999 ALLWISE W1 Band magnitude
352-361 F10.3 mag e_W1mag ?=-99999 ALLWISE W1 Band magnitude error
363-372 F10.3 mag W2mag ?=-99999 ALLWISE W2 Band magnitude
374-383 F10.3 mag e_W2mag ?=-99999 ALLWISE W2 Band magnitude error
385-394 F10.3 mag W3mag ?=-99999 ALLWISE W3 Band magnitude
396-405 F10.3 mag e_W3mag ?=-99999 ALLWISE W3 Band magnitude error
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Note (1): The Gaia DR1 does not provide a direct G magnitude error rather a
error on the flux, e_, we convert this to an estimate of the magnitude
error using the relation eGmag=1.0857*photgmeanfluxerror/photgmeanflux.
Note (2): Flag to show pm differ as follows:
0 = Difference of input and calculated proper motion is less than 20%
1 = Difference of input and calculated proper motion is more than 20%
Note (3): In one case the bibcode that is provided is "MAROCCOetal2017"
for an object that has parameters that are in a paper submitted but not yet
published.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- HIP/TYC HIPPARCOS or TYCHO2 name of primary
17- 35 I19 --- SourceID Gaia SourceID primary
37- 48 F12.8 deg RAdeg Right ascension (equinox J2000 epoch 2015)
50- 61 F12.8 deg DEdeg Declination (equinox J2000 epoch 2015)
63- 70 F8.1 mas/yr pmRA* Primary RA Proper motion from DR1,
pmRA*cosDE
72- 75 F4.1 mas/yr e_pmRA* Error in proper motion in RA, e_pmRA*cosDE
77- 84 F8.1 mas/yr pmDE Primary Dec Proper motion from DR1
86- 89 F4.1 mas/yr e_pmDE Error in proper motion in Dec
91- 94 I4 mas plx Primary DR1 parallax rounded value
96- 97 I2 mas e_plx Error in parallax rounded value
99-110 A12 --- SName Name of UCD in input catalog
112-119 F8.1 mas/yr pmRA*B UCD RA Proper motion from input catalog,
pmRA*cosDE
121-124 F4.1 mas/yr e_pmRA*B Error in UCD proper motion in RA, e_pmRA*cosDE
126-133 F8.1 mas/yr pmDEB UCD Dec Proper motion from input catalog
135-138 F4.1 mas/yr e_pmDEB Error in UCD proper motion in Dec
140-143 I4 mas spDist UCD Spectroscopic parallax rounded
145-146 I2 mas e_spDist Error in parallax rounded value
148-154 E7.1 --- Prob chance probability of not being a companion
156-164 A9 --- SpTypeO Optical UCD Spectra type from input catalog
166-174 A9 --- SpTypeN NIR UCD Spectra type from input catalog
176-187 F12.8 deg RABdeg UCD Right ascension (equinox J2000 epoch 2015)
189-200 F12.8 deg DEBdeg UCD Declination (equinox J2000 epoch 2015)
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 22 A22 --- Name Long name
25- 27 A3 --- SpTypeO Optical spectral type
29- 31 A3 --- r_SpTypeO Reference for SpTypeO (1)
33- 42 A10 --- SName Short name
45- 46 A2 --- SpTypeN NIR spectral type
48- 50 A3 --- r_SpTypeN Reference for SpTypeN (1)
52 I1 --- NPlot Plot label
54- 58 F5.2 mag DGmag Difference between Gaia DR1 G magnitude and
estimated G magnitude, G-Gest
60-469 A410 --- Rem Remarks
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Note (1): Spectral type references as follows:
(1) = Reid et al. (2008AJ....136.1290R 2008AJ....136.1290R, Cat. J/AJ/136/1290)
(2) = Lodieu et al. (2005A&A....436..853L, Cat. J/A+A/436/853)
(3) = Schmidt et al. (2010AJ....139.1808S 2010AJ....139.1808S, Cat. J/AJ/129/1808)
(4) = Bardalez Gagliuffi et al. (2014ApJ...794..143B 2014ApJ...794..143B)
(5) = West et al. (2008AJ....135..785W 2008AJ....135..785W, Cat. (J/AJ/135/785)
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Acknowledgements:
Richard Laurence Smart, smart(at)oato.inaf.it
(End) Richard Laurence Smart [OATo-INAF], Patricia Vannier [CDS] 18-Mar-2020