J/A+A/331/581 Rotation and activity in field M dwarfs (Delfosse+ 1998)
Rotation and chromospheric activity in field M dwarfs
Delfosse X., Forveille T., Perrier C., Mayor M.
<Astron. Astrophys. 331, 581 (1998)>
=1998A&A...331..581D 1998A&A...331..581D (SIMBAD/NED BibCode)
ADC_Keywords: Stars, M-type ; Space velocities ; Rotational velocities ;
Parallaxes, trigonometric
Keywords: stars: activity - stars: rotation - stars: chromospheres -
stars: coronae - stars: low-mass, brown dwarfs
Description:
We have obtained high resolution spectra for a volume-limited sample
of 118 field M dwarfs. From these observations we derive projected
rotational velocities and fluxes in the Hα and Hβ lines.
8 stars are double-lined spectroscopic binaries with measured or
probable periods short enough for rotation to be tidally synchronized
with the orbit, and another 11 are visual binaries where we cannot yet
separate the lines of the two stars. Of the remaining 99 stars,
24 have rotational velocities above our detection limit of ∼2km/s, and
some are quite fast rotators, including two with vsini>30km/s and one
with vsini∼50km/s. Given the small radii of M dwarfs, these moderate
rotational velocities correspond to rather short maximum rotational
periods, of only 7-8 hours.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 84 99 Basic parameters of the sample stars
table4.dat 86 101 Rotational, activity, and kinematics parameters
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Name
12- 13 I2 h RAh Right ascension (J2000)
15- 16 I2 min RAm Right ascension (J2000)
18- 21 F4.1 s RAs Right ascension (J2000)
23 A1 --- DE- Declination sign
24- 25 I2 deg DEd Declination (J2000)
27- 28 I2 arcmin DEm Declination (J2000)
30- 33 F4.1 arcsec DEs Declination (J2000)
35- 38 A4 --- SpType Spectral type (1)
39 A1 --- n_SpType [a] Note on Spectral type (1)
41- 44 F4.2 mag R-I R-I color index (2)
45 A1 --- n_R-I [bcd] Note on R-I (2)
47- 51 F5.2 mag VMAG V Absolute magnitude
53- 57 F5.2 mag Mbol Bolometric absolute magnitude
59- 61 I3 mas plx Trigonometric parallax
62 A1 --- n_plx [ef] Note on Plx (3)
64- 65 I2 mas e_plx rms uncertainty on plx
67- 72 F6.3 mas/yr pmRA Proper motion in RA (3)
74- 79 F6.3 mas/yr pmDE Proper motion in DE (3)
81- 84 I4 km/s RV Radial velocity
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Note (1): Spectral type are from Reid et al (1995AJ....110.1838R 1995AJ....110.1838R), except when
n_Type=a, then spectral type from Henry et al. (1994AJ....108.1437H 1994AJ....108.1437H).
Note (2): The (R-I) is in Cousin system and is from Leggett's
(1992ApJS...82..351L 1992ApJS...82..351L) compilation except when
n_R-I=b, data from the CNS3 catalog (Gliese and Jahreiss, 1991,
Cat. V/70; the Kron R-I in the CNS3 were transformed to the
Cousins system using the Bessell (1983PASP...95..480B 1983PASP...95..480B) relation,
(R-I)c=1.20(R-I)k+0.08);
n_R-I=c, data from Bessell (1990A&AS...83..357B 1990A&AS...83..357B);
n_R-I=d, data estimated from spectral type, using Leggett's
(1992ApJS...82..351L 1992ApJS...82..351L) relation for the Young Disk.
Note (3): Parallax and proper motion are from
e: the Yale General Catalogue of Trigonometric Stellar Parallaxes
(Van Altena et al. 1991, see Cat. I/238), or
f: the Hipparcos input catalogue (Turon et al., 1993, Cat. I/196).
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Name
11- 15 F5.2 km/s Sig Width of correlation profile (1)
16 A1 --- n_Sig [a] Note on Sig (1)
17- 20 F4.2 km/s e_Sig Standard error on Sig (2)
22 A1 --- l_vsini Limit flag on vsini
23- 27 F5.2 km/s vsini Projected rotational velocities
29- 31 F3.1 km/s e_vsini ? Standard error on vsini (2)
33- 37 F5.2 [10-7W] Lbol Logarithm of bolometric luminosities
39- 43 F5.2 [10-7W] LHalpha ? Logarithm of Hα luminosities
45- 47 F3.2 [10-7W] e_LHalpha ? rms uncertainty on LHalpha
49- 53 F5.2 [10-7W] LHbeta ? Logarithm of Hβ luminosities
55- 58 F4.2 [10-7W] e_LHbeta ? rms uncertainty on LHbeta
61 A1 --- l_Lx Limit flag on Lx
62- 66 F5.2 [10-7W] Lx Logarithm of the X luminosities (3)
68- 70 I3 km/s Uvel Space motion (4)
71 A1 --- n_Uvel [bc] Note on Uvel (5)
73- 76 I4 km/s Vvel Space motion (4)
77 A1 --- n_Vvel [bc] Note on Vvel (5)
79- 82 I4 km/s Wvel Space motion (4)
83 A1 --- n_Wvel [bc] Note on Wvel (5)
85- 86 A2 --- Pop [YDOH ] Dynamic population (6)
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Note (1): With a K0 template, except when n_sig=a, then with the M0 template.
Note (2): The quoted uncertainty on Sig is that due to photon and readout noise,
while the standard error on vsini also includes a 200m/s dispersion
on Sig_0, the width of the correlation profile of a non rotating star
Note (3): From Schmitt et al. (1995ApJ...450..392S 1995ApJ...450..392S) and the
ROSAT all sky survey (Voges et al., 1996, Cat. IX/10).
Note (4): The UVW space motion are heliocentric, with U positive toward
the Galactic anticenter.
Note (5): b: space velocities were computed using an inaccurate radial velocity
(±2km/s), because we have not yet covered a full orbital period.
c: space velocities use the barycentric radial velocity from
Marcy & Chen (1992ApJ...390..550M 1992ApJ...390..550M).
Note (6): The code is:
YD: young disk
YO: young-old disk
OD: old disk
OH: old disk-Halo
H: Halo
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Acknowledgements: Xavier Delfosse
(End) Patricia Bauer [CDS] 13-Nov-1997