J/A+A/620/A180 Stellar properties of M dwarfs (Rajpurohit+, 2018)
Exploring the stellar properties of M dwarfs with high-resolution spectroscopy
from the optical to the near-infrared.
Rajpurohit A.S., Allard F., Rajpurohit S., Sharma R., Teixeira G.D.C.,
Mousis O., Kamlesh R.
<Astron. Astrophys. 620, A180 (2018)>
=2018A&A...620A.180R 2018A&A...620A.180R (SIMBAD/NED BibCode)
ADC_Keywords: Stars, M-type ; Abundances, [Fe/H] ; Effective temperatures ;
Photometry, infrared
Keywords: stars: fundamental parameters - stars: low-mass - stars: atmospheres
Abstract:
Being the most numerous and oldest stars in the galaxy, M dwarfs are
objects of great interest for exoplanet searches. The presence of
molecules in their atmosphere complicates our understanding of their
atmospheric properties. But great advances have recently been made in
the modeling of M dwarfs due to the revision of solar abundances.
We aim to determine stellar parameters of M dwarfs using high
resolution spectra (R∼90000) simultaneously in the visible and the
near-infrared. The high resolution spectra and broad wavelength
coverage provide an unique opportunity to understand the onset of dust
and cloud formation at cool temperatures. Furthermore, this study will
help in understanding the physical processes which occur in a cool
atmospheres, particularly, the redistribution of energy from the
optical to the near-infrared.
The stellar parameters of M dwarfs in our sample have been determined
by comparing the high resolution spectra both in the optical and in
the near-infrared simultaneously observed by CARMENES with the
synthetic spectra obtained from the BT-Settl model atmosphere. The
detailed spectral synthesis of these observed spectra both in the
optical and in the near-infrared helps to understand the missing
continuum opacity.
For the first time, we derive fundamental stellar parameters of M
dwarfs using the high resolution optical and near-infrared spectra
simultaneously. We determine Teff, logg and [M/H] for 292 M dwarfs of
spectral type M0 to M9, where the formation of dust and clouds are
important. The derived Teff for the sample ranges from 2300 to 4000K,
values of log g ranges from 4.5≤logg≤5.5 and the resulting
metallicity ranges from -0.5≤[M/H]≤+0.5. We have also explored the
possible differences in Teff, logg and [M/H] by comparing them with
other studies of the same sample of M dwarfs.
Description:
Studied sample with their stellar parameters derived from this work
and from Passegger et al. (2018A&A...615A...6P 2018A&A...615A...6P). Their spectral types,
visible and NIR photometry are taken from SIMBAD and 2MASS.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 92 292 M dwarfs parameters
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See also:
J/A+A/577/A128 : CARMENES input catalog of M dwarfs I (Alonso-Floriano+, 2015)
J/A+A/597/A47 : CARMENES input catalog of M dwarfs II (Cortes-Contreras+ 2017)
J/A+A/609/A117 : CARMENES radial velocity curves of 7 M-dwarf (Trifonov+, 2018)
J/A+A/609/L5 : CARMENES radial velocity curves of HD147379 b (Reiners+, 2018)
J/A+A/612/A49 : 324 CARMENES M dwarfs velocities (Reiners+, 2018)
J/A+A/614/A122 : Radial-velocity of CARMENES M dwarfs (Tal-Or+, 2018)
J/A+A/615/A6 : Photospheric parameters of CARMENES stars (Passegger+, 2018)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 21 A21 --- Name Name
23- 26 A4 --- SpType Spectral type
28- 33 F6.3 mag Vmag ? V magnitude
35- 40 F6.3 mag Jmag ? 2MASS J magnitude
42- 47 F6.3 mag Hmag ? 2MASS H magnitude
49- 54 F6.3 mag Kmag ? 2MASS K magnitude
56- 59 I4 K Teff Effective temperature, this study
61- 64 F4.2 [cm/s2] logg Surface gravity, this study
66- 70 F5.2 [-] [M/H] Metallicity [M/H], this study
72- 75 F4.2 --- chi2 chi2, this study
77- 80 I4 K TeffP ? Effective temperature, Passegger et al.
(2018, Cat. J/A+A/615/A6)
82- 85 F4.2 [cm/s2] loggP ? Surface gravity, Passegger et al.
(2018, Cat. J/A+A/615/A6)
87- 92 F6.3 [-] [M/H]P ? Metallicity [M/H], Passegger et al.
(2018, Cat. J/A+A/615/A6)
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Acknowledgements:
Arvind Singh Rajpurohit, arvindr(at)prl.res.in
(End) Patricia Vannier [CDS] 05-Nov-2018