J/ApJ/821/93 Rotation & Galactic kinematics of mid M dwarfs (Newton+, 2016)
The rotation and Galactic kinematics of mid M dwarfs in the solar neighborhood.
Newton E.R., Irwin J., Charbonneau D., Berta-Thompson Z.K., Dittmann J.A.,
West A.A.
<Astrophys. J., 821, 93-93 (2016)>
=2016ApJ...821...93N 2016ApJ...821...93N (SIMBAD/NED BibCode)
ADC_Keywords: Stars, M-type ; Rotational velocities ; Stars, masses ;
Proper motions
Keywords: stars: kinematics and dynamics; stars: low-mass; stars: rotation;
starspots
Abstract:
Rotation is a directly observable stellar property, and it drives
magnetic field generation and activity through a magnetic dynamo.
Main-sequence stars with masses below approximately 0.35M☉
(mid-to-late M dwarfs) are fully convective, and are expected to have
a different type of dynamo mechanism than solar-type stars.
Measurements of their rotation rates provide insight into these
mechanisms, but few rotation periods are available for these stars at
field ages. Using photometry from the MEarth Project, we measure
rotation periods for 387 nearby, mid-to-late M dwarfs in the northern
hemisphere, finding periods from 0.1 to 140 days. The typical rotator
has stable, sinusoidal photometric modulations at a semi-amplitude of
0.5%-1%. We find no period-amplitude relation for stars below
0.25M☉ and an anticorrelation between period and amplitude for
higher-mass M dwarfs. We highlight the existence of older, slowly
rotating stars without Hα emission that nevertheless have strong
photometric variability. We use parallaxes, proper motions, radial
velocities, photometry, and near-infrared metallicity estimates to
further characterize the population of rotators. The Galactic
kinematics of our sample is consistent with the local population of G
and K dwarfs, and rotators have metallicities characteristic of the
solar neighborhood. We use the W space velocities and established
age-velocity relations to estimate that stars with P<10d have ages of
on average <2Gyr, and that those with P>70d have ages of about 5Gyr.
The period distribution is dependent on mass: as the mass decreases,
the slowest rotators at a given mass have longer periods, and the
fastest rotators have shorter periods. We find a lack of stars with
intermediate rotation periods, and the gap between the fast and slow
rotators is larger for lower masses. Our data are consistent with a
scenario in which these stars maintain rapid rotation for several
gigayears, then spin down quickly, reaching periods of around 100d by
a typical age of 5Gyr.
Description:
In this work, we extend the analysis of Irwin et al. (2011ApJ...727...56I 2011ApJ...727...56I)
to the full northern sample of M dwarfs observed by MEarth.
MEarth-North is located at the Fred Lawrence Whipple Observatory, on
Mount Hopkins, Arizona, and has been operational since 2008 September.
See section 2 for further explanations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 219 1886 Kinematics and rotation periods for all
rotators and non-rotators
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See also:
I/298 : LSPM-North Catalog (Lepine+ 2005)
J/ApJ/818/153 : MEarth photometry: nearby M-dwarf (Dittmann+, 2016)
J/ApJ/812/3 : MEarth mid-to-late M dwarfs rotation+kinematics (West+, 2015)
J/ApJ/800/85 : Teff, radii and luminosities of cool dwarfs (Newton+, 2015)
J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)
J/AJ/147/20 : Spectroscopy of 447 nearby M dwarfs (Newton+, 2014)
J/AJ/146/156 : APOGEE M-dwarf survey. I. 1st yr velocities (Deshpande+, 2013)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/ApJ/767/95 : Improved parameters of smallest KIC stars (Dressing+, 2013)
J/AcA/63/53 : ASAS photometry of ROSAT sources. II. (Kiraga+, 2013)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/AJ/144/99 : Near-IR spectroscopy of 36 late M dwarfs (Deshpande+, 2012)
J/AJ/144/93 : Close white dwarf + M dwarf binaries (WD+dM) (Morgan+, 2012)
J/AJ/143/93 : Rotational velocities in early-M stars (Reiners+, 2012)
J/A+A/532/A10 : RACE-OC project. II. (Messina+, 2011)
J/ApJ/733/L9 : Stellar rotation for 71 NGC 6811 members (Meibom+, 2011)
J/ApJ/723/684 : NIRSPEC ultracool dwarf radial velocity survey (Blake+, 2010)
J/MNRAS/407/1657 : Rotation velocities of dwarf M stars (Houdebine, 2010)
J/ApJ/705/1416 : Volume-limited sample of M7-M9.5 dwarfs <20pc (Reiners+, 2009)
J/ApJ/704/975 : Rotational velocities for M dwarfs (Jenkins+, 2009)
J/AJ/137/1 : PMs & astrometry of late-type dwarfs (Faherty+, 2009)
J/MNRAS/390/567 : Magnetic field and velocity of mid M dwarfs (Morin+, 2008)
J/MNRAS/390/545 : Magnetic field & velocity of early M dwarfs (Donati+, 2008)
J/AJ/135/785 : SDSS-DR5 low-mass star spectroscopic sample (West+, 2008)
J/A+A/480/91 : Galactic disk stars distribution. IV. (Soubiran+, 2008)
J/AJ/133/2258 : Activity and kinematics of ultracool dwarfs (Schmidt+, 2007)
J/A+A/467/785 : SuperWASP/ROSAT periodic variable stars (Norton+, 2007)
J/AJ/130/1680 : LSPM-North proper-motion catalog nearby stars (Lepine+, 2005)
J/A+A/430/165 : Radial velocities for 6691 K and M giants (Famaey+, 2005)
J/A+A/410/527 : Abundances in the Galactic disk (Bensby+, 2003)
J/AJ/123/3356 : Palomar/MSU nearby star spectrosc. survey. III. (Gizis+, 2002)
J/MNRAS/301/1031 : High resolution spectra of VLM stars (Tinney+ 1998)
J/A+A/331/581 : Rotation and activity in field M dwarfs (Delfosse+ 1998)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Type Source type (1)
3- 19 A17 --- 2MASS 2MASS identifier (JHHMMSSss+DDMMSSs)
21- 31 A11 --- LSPM LSPM identifier (JHHMM+DDMM)
33- 42 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000)
44- 54 F11.8 deg DEdeg Declination in decimal degrees (J2000)
56- 61 F6.4 arcsec plx [0.006/0.6]? Parallax
63- 68 F6.4 arcsec e_plx [0/0.02]? Uncertainty in plx
70- 88 A19 --- r_plx ADS bibliography code reference for plx
90- 96 F7.4 arcsec/yr pmRA [-9.7/19.6] Proper motion along RA
98-104 F7.4 arcsec/yr pmDE [-5.2/10.3] Proper motion along Declination
106-111 F6.1 km/s RVel [-267/254]? Radial velocity
113-116 F4.1 km/s e_RVel [0/44]? Uncertainty in RVel
118-136 A19 --- r_RVel ADS bibliography code reference for RVel
138-143 F6.1 km/s U [-146/269]? Velocity towards Galactic center
145-150 F6.1 km/s V [-221/65]? Velocity in direction
of galactic rotation
152-157 F6.1 km/s W [-155/224]? Velocity toward the North
Galactic Pole
159-166 F8.3 d Per [0.1/1500] Photometric rotation period
168-173 F6.4 mag Amp [0.0001/0.5] Semi-amplitude of variability
175-180 F6.4 mag e_Amp [0.001/0.4] Uncertainty in Amp
182-186 F5.3 Msun Mass [0.05/0.8]? Stellar mass
188-192 F5.3 Rsun Rad [0.1/0.8]? Stellar radius
194-198 F5.1 km/s VRot [0/383] Rotational velocity
200 I1 --- Cont [1/4]? Contamination flag (2)
202-205 I4 --- N [28/6197] Number of data points
207-212 F6.4 --- Err [0.0007/0.02] Median error
214-219 I6 --- Fstat [4/10236] F-test statistic (3)
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Note (1): Source type as follows:
A = Grade A rotators;
B = Grade B rotators;
U = Possible or uncertain detection;
N = Non-detection or undetermined detection.
Note (2): Indicating known or suspected contamination by a common
proper motion companion or background source. Flag as follows:
1 = Bright contaminant;
2 = Faint contaminant;
3 = Very faint contaminant;
4 = Potentially overluminous.
Note (3): We calculate the F-test statistic (which measures the amount of
variance that is explained by the additional parameters in the
alternative model) at each frequency and select the one with the
highest statistic as the candidate frequency. See section 3.1.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 25-Jul-2016