J/MNRAS/390/1517 Proper motions of field L and T dwarfs (Casewell+, 2008)
Proper motions of field L and T dwarfs - II.
Casewell S.L., Jameson R.F., Burleigh M.R.
<Mon. Not. R. Astron. Soc., 390, 1517-1526 (2008)>
=2008MNRAS.390.1517C 2008MNRAS.390.1517C
ADC_Keywords: Clusters, open ; Stars, dwarfs ; Proper motions
Keywords: stars: kinematics - stars: low-mass, brown dwarfs -
open clusters and associations: individual: Ursa Major -
open clusters and associations: individual: Hyades -
open clusters and associations: individual: Pleiades
Abstract:
By using images taken with Wide Field Camera (WFCAM) on United Kingdom
Infrared Telescope (UKIRT) and Son of ISAAC (SofI) on the New
Technology Telescope (NTT) and combining them with Two Micron All Sky
Survey (2MASS) we have measured proper motions for 125 L and T dwarfs
in the dwarf archive. Two of these L dwarfs appear to have M dwarf
common proper motion companions, and two also appear to be
high-velocity dwarfs, indicating possible membership of the thick
disc. We have also compared the motion of these 125 objects to that of
numerous moving groups, and have identified new members of the Hyades,
Ursa Major and Pleiades moving groups. These new objects, as well as
those identified in Jameson et al. have allowed us to refine the L
dwarf sequence for Ursa Major that was defined by Jameson et al,
2008 (Cat. J/MNRAS/384/1399).
Description:
In order to measure proper motions for known L and T dwarfs we
observed a sample of the known L and T dwarfs from the online dwarf
archive (detailed in Tables 1 and 2, see
http://spider.ipac.caltech.edu/staff/davy/ARCHIVE/ for discovery
references) with J-band magnitudes of less than 16.5. 143 of these
objects were presented in Jameson et al. (2008, Cat.
J/MNRAS/384/1399). To complete the sample, 125 additional objects
have been observed, 91 with declination (Dec.) between -30° and
+60°, and 34 with Dec. of less than -30°.
This first group were imaged using WFCAM on UKIRT over the period of
2006 June to 2008 March.
The second group were imaged using SofI on the NTT between 2007 April
2 and 2007 August 31.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 112 36 2MASS name, positions, proper motions and 2MASS
magnitudes for all the L and T dwarfs for which
we measured proper motions using SofI
table2.dat 112 89 2MASS name, positions, proper motions and 2MASS
magnitudes for all the L and T dwarfs for which
we measured proper motions using WFCAM
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)
J/ApJ/564/421 : Spectra of T dwarfs. I. (Burgasser+, 2002)
J/AJ/126/2487 : T dwarfs in the southern hemisphere (Burgasser+, 2003)
J/AJ/127/3553 : JHK photometry and spectroscopy for L & T dwarfs (Knapp+ 2004)
J/AJ/131/2722 : New L and T dwarfs from the SDSS (Chiu+, 2006)
J/ApJ/648/629 : Radio observations of late M, L, and T dwarfs (Berger+, 2006)
J/ApJ/651/502 : Spitzer IRAC photometry of M, L, and T dwarfs (Patten+, 2006)
J/other/ARA+A/43.195 : L and T dwarf stars (Kirkpatrick, 2005)
J/MNRAS/384/1399 : Proper motions of field L and T dwarfs. I (Jameson+, 2008)
http://spider.ipac.caltech.edu/staff/davy/ARCHIVE/ : Archive of M,L,T dwarfs
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- 2MASS 2MASS name (JHHMMSSss+DDMMSSs)
19- 20 I2 h RAh Right ascension (J2000)
22- 23 I2 min RAm Right ascension (J2000)
25- 29 F5.2 s RAs Right ascension (J2000)
31 A1 --- DE- Declination sign (J2000)
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 42 F5.2 arcsec DEs Declination (J2000)
44- 50 F7.2 mas/yr pmRA Proper motion along RA (pmRA*cosDE)
52- 57 F6.3 mas/yr e_pmRA rms uncertainty on pmRA
59- 66 F8.3 mas/yr pmDE Proper motion along DE
67- 73 F7.3 mas/yr e_pmDE rms uncertainty on pmDE
75- 80 F6.3 mag Jmag 2MASS J magnitude
82- 86 F5.3 mag e_Jmag rms uncertainty on Jmag
88- 93 F6.3 mag Hmag 2MASS H magnitude
95- 99 F5.3 mag e_Hmag ?=9.999 rms uncertainty on Hmag
101-106 F6.3 mag Ksmag 2MASS Ks magnitude
108-112 F5.3 mag e_Ksmag ?=9.999 rms uncertainty on Ksmag
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Mar-2009