J/ApJ/648/629 Radio observations of late M, L, and T dwarfs (Berger+, 2006)
Radio observations of a large sample of late M, L, and T dwarfs:
the distribution of magnetic field strengths.
Berger E.
<Astrophys. J., 648, 629-636 (2006)>
=2006ApJ...648..629B 2006ApJ...648..629B
ADC_Keywords: Stars, dwarfs ; Stars, late-type ; Radio sources ; Magnetic fields
Keywords: radio continuum: stars - stars: activity -
stars: low-mass, brown dwarfs - stars: magnetic fields
Abstract:
I present radio observations of 90 dwarf stars and brown dwarfs of
spectral type M5-T8. Three sources exhibit radio activity, in addition
to the six objects previously detected in quiescence and outburst,
leading to an overall detection rate of ∼10% for objects later than
M7.
Description:
I observed a sample of 21 late M, L, and T dwarfs with the Very Large
Array (VLA) at 8.46GHz using the standard continuum mode with MHz
contiguous bands at each frequency. In addition to our observations
we obtained and reduced all publicly available observations of late-M,
L and T dwarfs from the VLA archive, and collected all measurements
published in the literature.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 108 94 Radio Observations of M, L, and T Dwarfs
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See also:
J/A+A/326/249 : Chromospheric models of dwarf M stars (Mauas+ 1997)
J/A+A/331/581 : Rotation and activity in field M dwarfs (Delfosse+ 1998)
J/A+A/380/590 : 30 DENIS late-M dwarfs between 15 and 30pc (Phan-Bao+, 2001)
J/ApJ/564/421 : Spectra of T dwarfs. I. (Burgasser+, 2002)
J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)
J/A+A/401/959 : 35 DENIS late-M dwarfs between 10 and 30pc (Phan-Bao+, 2003)
J/A+A/439/1137 : PHOENIX model chromospheres of M dwarfs (Fuhrmeister+, 2005)
J/AJ/126/2487 : T dwarfs in the southern hemisphere (Burgasser+, 2003)
J/AJ/127/3553 : L and T dwarfs JHK photometry & spectroscopy (Knapp+, 2004)
J/AJ/130/1871 : Spectroscopic survey of M dwarfs (Bochanski+, 2005)
J/other/ARA+A/43.195 : L and T dwarf stars (Kirkpatrick, 2005)
J/AJ/131/2722 : New L and T dwarfs from the SDSS (Chiu+, 2006)
J/AJ/132/866 : New M dwarfs in solar neighborhood (Riaz+, 2006)
J/AJ/132/891 : Binaries among nearby L dwarfs (Reid+, 2006)
J/ApJ/637/1067 : T dwarfs near-IR spectral classification (Burgasser+, 2006)
J/MNRAS/383/831 : New DENIS nearby L and late-M dwarfs (Phan-Bao+, 2008)
J/PASP/118/659 : RI photometry of 2MASS late M and L dwarfs (Liebert+, 2006)
J/ApJ/651/502 : Spitzer IRAC photometry of M, L and T dwarfs (Patten+, 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Fl [F] F when flux at Flare
3- 4 I2 h RAh Right ascension (J2000) (1)
6- 7 I2 min RAm Right ascension (J2000) (1)
9- 12 F4.1 s RAs Right ascension (J2000) (1)
14 A1 --- DE- Declination sign (J2000) (1)
15- 16 I2 deg DEd Declination (J2000) (1)
18- 19 I2 arcmin DEm Declination (J2000) (1)
21- 22 I2 arcsec DEs Declination (J2000) (1)
24- 27 A4 --- Sp Spectral type
29- 33 F5.2 mag Jmag ?=- J magnitude
35- 39 F5.2 mag Kmag ?=- K magnitude
41- 46 F6.2 mas plx ?=- Parallax
48 A1 --- l_FR Limit flag on FR
49- 54 I6 uJy FR Radio flux density at 8.46GHz
56- 60 I5 uJy e_FR ? rms uncertainty on FR
63- 66 F4.1 km/s vsini ? Rotational velocity
68- 72 F5.2 [solLum] Lbol ? Bolometric luminosity
74 A1 --- l_LHa/Lbol Limit flag on LHa/Lbol
75- 79 F5.2 [---] LHa/Lbol ? Ratio of Hα to bolometric luminosity
80 A1 --- n_LHa/Lbol [a] when LHa/Lbol calculated from H line (2)
81- 85 F5.3 solRad R ? Stellar radius
87- 90 I4 K T ? Surface temperature
92-104 A13 ---- Name Name, when exist, or Flare
106-108 A3 --- Ref References (3)
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Note (1): Objects identified as [B2006] JHHMMSS.s+DDMMSS in Simbad.
Note (2): 'a' when LHa/Lbol calculated from the Hα line
equivalent width using the conversion of West et al. (2004,
Cat. J/AJ/128/426)
Note (3): References as follows:
1 = Berger, 2002ApJ...572..503B 2002ApJ...572..503B
2 = Burgasser & Putman, 2005ApJ...626..486B 2005ApJ...626..486B
3 = Krishnamurthi et al., 1999AJ....118.1369K 1999AJ....118.1369K
4 = Berger et al., 2001Natur.410..338B 2001Natur.410..338B
5 = Berger et al., 2005ApJ...627..960B 2005ApJ...627..960B
6 = Audard et al., 2005ApJ...625L..63A 2005ApJ...625L..63A
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 17-Jul-2008