J/AJ/155/225 M dwarf stars rotational broadening measurements (Kesseli+, 2018)
Magnetic inflation and stellar mass.
II. On the radii of single, rapidly rotating, fully convective M-dwarf stars.
Kesseli A.Y., Muirhead P.S., Mann A.W., Mace G.
<Astron. J., 155, 225-225 (2018)>
=2018AJ....155..225K 2018AJ....155..225K (SIMBAD/NED BibCode)
ADC_Keywords: Stars, dwarfs ; Stars, M-type ; Rotational velocities
Keywords: stars: fundamental parameters - stars: low-mass -
stars: magnetic field - stars: rotation - stars: statistics
Abstract:
Main-sequence, fully convective M dwarfs in eclipsing binaries are
observed to be larger than stellar evolutionary models predict by as
much as 10%-15%. A proposed explanation for this discrepancy involves
effects from strong magnetic fields, induced by rapid rotation via the
dynamo process. Although, a handful of single, slowly rotating M dwarfs
with radius measurements from interferometry also appear to be larger
than models predict, suggesting that rotation or binarity specifically
may not be the sole cause of the discrepancy. We test whether single,
rapidly rotating, fully convective stars are also larger than expected
by measuring their Rsini distribution. We combine photometric rotation
periods from the literature with rotational broadening (vsini)
measurements reported in this work for a sample of 88 rapidly rotating
M dwarf stars. Using a Bayesian framework, we find that stellar
evolutionary models underestimate the radii by 10%-15%-2.5+3, but
that at higher masses (0.18<M<0.4 MSun), the discrepancy is only about
6% and comparable to results from interferometry and eclipsing binaries.
At the lowest masses (0.08<M<0.18 MSun), we find that the discrepancy
between observations and theory is 13%-18%, and we argue that the
discrepancy is unlikely to be due to effects from age. Furthermore, we
find no statistically significant radius discrepancy between our sample
and the handful of M dwarfs with interferometric radii. We conclude that
neither rotation nor binarity are responsible for the inflated radii
of fully convective M dwarfs, and that all fully convective M dwarfs
are larger than models predict.
Description:
Data were collected between 2016 October and 2017 November using the
Immersion GRating INfrared Spectrograph (IGRINS; Park et al.
2014SPIE.9147E..1DP) on Lowell Observatory's 4.3 m Discovery Channel
Telescope (DCT) at and the 2.7 m Harlan J. Smith Telescope at McDonald
Observatory. We also used iSHELL (Rayner et al. 2016SPIE.9908E..84R 2016SPIE.9908E..84R) on
NASA's 3.0 m Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii.
IGRINS is a high-resolution (R∼45000) infrared spectrograph that
simultaneously collects H and K-band spectra (Mace et al.
2016SPIE.9908E..0CM). iSHELL has a spectral resolution of 75000 at
our chosen wavelength region in the K-band (2.26-2.55 µm).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 106 88 Observed targets
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See also:
III/226 : Rotational Velocities of Stars (Glebocki+ 2000)
J/A+A/331/581 : Rotation and activity in field M dwarfs (Delfosse+ 1998)
J/ApJ/704/975 : Rotational velocities for M dwarfs (Jenkins+, 2009)
J/MNRAS/407/1657 : Rotation velocities of dwarf M stars (Houdebine, 2010)
J/AJ/146/156 : APOGEE M-dwarf survey. I. First year velocities
(Deshpande+, 2013)
J/ApJ/821/93 : Rotation + Galactic kinematics of mid M dwarfs
(Newton+, 2016)
J/MNRAS/463/1844 : M dwarfs rotation-activity relation (Stelzer+, 2016)
J/A+A/612/A49 : 324 CARMENES M dwarfs velocities (Reiners+, 2018)
J/AJ/155/38 : The rotation of M dwarfs observed by APOGEE (Gilhool+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- 2MASS 2MASS name (JHHMMSSss+DDMMSSs)
19- 29 A11 "date" Date UT date of observation
31- 45 A15 --- Tel Telescope (DCT, Harlan J. Smith or IRTF)
47- 52 A6 --- Inst Instrument (IGRINS or iSHELL)
54- 58 F5.3 d Prot [0.102/4.755] Rotation period from
Newton et al. (2016, J/ApJ/821/93)
60- 63 F4.1 km/s vsini [2.8/66]? Rotational broadening
65- 67 F3.1 km/s e_vsini [0.2/3.3]? Uncertainty in vsini
69- 72 F4.1 km/s vsiniP1 [2.4/51.3]? First value of previous rotational
broadening
74- 76 F3.1 km/s e_vsiniP1 [0.2/3.1]? Uncertainty in vsiniP1
78- 81 F4.1 km/s vsiniP2 [5.9/15.6]? Second value of previous
rotational broadening
83- 85 F3.1 km/s e_vsiniP2 [0.8/1.5]? Uncertainty in vsiniP2
87- 90 F4.1 km/s vsiniP3 [11.4/15]? Third value of previous rotational
broadening
92- 94 F3.1 km/s e_vsiniP3 [0.7/1]? Uncertainty in vsiniP3
96- 98 A3 --- r_vsiniP1 Reference for vsiniP1 (1)
100-102 A3 --- r_vsiniP2 Reference for vsiniP2 (1)
104-106 A3 --- r_vsiniP3 Reference for vsiniP3 (1)
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Note (1): Reference as follows:
F18 = Fouque et al. (2018MNRAS.475.1960F 2018MNRAS.475.1960F);
R18 = Reiners et al. (2018, J/A+A/612/A49);
J09 = Jenkins et al. (2009, J/ApJ/704/975);
R02 = Reid et al. (2002AJ....124..519R 2002AJ....124..519R);
D13 = Deshpande et al. (2013, J/AJ/146/156);
D15 = Davison et al. (2015AJ....149..106D 2015AJ....149..106D);
D98 = Delfosse et al. (1998, J/A+A/331/581).
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History:
From electronic version of the journal
References:
Han et al. Paper I. 2017AJ....154..100H 2017AJ....154..100H
(End) Tiphaine Pouvreau [CDS] 13-Dec-2018