J/A+A/615/A6 Photospheric parameters of CARMENES stars (Passegger+, 2018)
The CARMENES search for exoplanets around M dwarfs.
Photospheric parameters of target stars from high-resolution spectroscopy.
Passegger V.M., Reiners A., Jeffers S.V., Wende-von Berg S., Schaefer P.,
Caballero J.A., Schweitzer A., Amado P.J., Bejar V.J.S.,
Cortes-Contreras M., Hatzes A.P., Kuerster M., Montes D., Pedraz S.,
Quirrenbach A., Ribas I., Seifert W.
<Astron. Astrophys. 615, A6 (2018)>
=2018A&A...615A...6P 2018A&A...615A...6P (SIMBAD/NED BibCode)
ADC_Keywords: Stars, M-type ; Abundances, [Fe/H] ; Effective temperatures ;
Spectroscopy ; Stars, masses
Keywords: astronomical databases: miscellaneous - methods: data analysis -
techniques: spectroscopic - stars: fundamental parameters -
stars: late-type - stars: low-mass
Abstract:
The new CARMENES instrument comprises two high-resolution and
high-stability spectrographs that are used to search for habitable
planets around M dwarfs in the visible and near-infrared regime via
the Doppler technique.
Characterising our target sample is important for constraining the
physical properties of any planetary systems that are detected. The
aim of this paper is to determine the fundamental stellar parameters
of the CARMENES M-dwarf target sample from high-resolution spectra
observed with CARMENES. We also include several M-dwarf spectra
observed with other high-resolution spectrographs, that is CAFE,
FEROS, and HRS, for completeness.
We used a χ2 method to derive the stellar parameters effective
temperature T_eff, surface gravity log g, and metallicity [Fe/H] of
the target stars by fitting the most recent version of the
PHOENIX-ACES models to high-resolution spectroscopic data. These
stellar atmosphere models incorporate a new equation of state to
describe spectral features of low-temperature stellar atmospheres.
Since Teff, logg, and [Fe/H] show degeneracies, the surface gravity
is determined independently using stellar evolutionary models.
We derive the stellar parameters for a total of 300 stars. The fits
achieve very good agreement between the PHOENIX models and observed
spectra. We estimate that our method provides parameters with
uncertainties of σTeff=51K, σlogg=0.07, and
σ[Fe/H]=0.16, and show that atmosphere models for low-mass
stars have significantly improved in the last years. Our work also
provides an independent test of the new PHOENIX-ACES models, and a
comparison for other methods using low-resolution spectra. In
particular, our effective temperatures agree well with literature
values, while metallicities determined with our method exhibit a
larger spread when compared to literature results.
Description:
We present basic astronomical parameters of 300 M dwarfs within the
CARMENES survey. For each star, we provide Carmencita identifier
(Karmn), Simbad name, equatorial coordinates, spectral type, effective
temperature, surface gravity, metallicity, rotational velocity,
stellar mass, CaII emission flag and instrument with which the
spectrum was obtained.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 137 300 Basic astrophysical parameters of investigated
M dwarfs
refs.dat 175 12 References
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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)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Karmn Carmencita identifier
14- 34 A21 --- Name Star name
36- 41 A6 --- GJ GJ number
44- 45 I2 h RAh Right Ascension (J2016 )
47- 48 I2 min RAm Right Ascension (J2016 )
50- 54 F5.2 s RAs Right Ascension (J2016 )
57 A1 --- DE- Declination sign (J2016 )
58- 59 I2 deg DEd Declination (J2016)
61- 62 I2 arcmin DEm Declination (J2016)
64- 67 F4.1 arcsec DEs Declination (J2016)
70- 74 A5 --- SpType MK spectral type
77- 80 I4 K Teff Effective temperature (1)
83- 86 F4.2 [cm/s2] logg Surface gravity (1)
89- 93 F5.2 [-] [Fe/H] Metallicity (1)
96 A1 --- f_vsini Upper limit flag for rotational velocity
97- 99 F3.1 km/s vsini Rotational velocity
102-106 F5.3 Msun Mass ?=- Stellar mass
109 I1 --- f_CaII [0/1] Flag for Ca II IRT emission;
1 if emission visible
112-116 A5 --- Inst Instrument used for observations (2)
119-137 A19 --- Ref Bibcode of reference to vsini,
in refs.dat file
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Note (1): Errors in Teff, logg and [Fe/H] are the same for all stars:
e_Teff = 51 K, e_logg = 0.07, e_[Fe/H] = 0.16
Note (2): Instrument used for observations as follows:
CARM = CARMENES single spectrum
CARM+ = CARMENES co-added spectrum
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- BibCode BibCode
21- 40 A20 --- Aut Author's name
43- 58 A16 --- Com Comments
60-175 A116 --- Title Title of the paper
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Acknowledgements:
Vera Maria Passegger, vpassegger(at)hs.uni-hamburg.de
References:
Alonso-Floriano et al., Paper I 2015A&A...577A.128A 2015A&A...577A.128A, Cat. J/A+A/577/A128
Cortes-Contreras et al., Paper II 2017A&A...597A..47C 2017A&A...597A..47C, Cat. J/A+A/597/A47
Garcia-Piquer et al., 2017A&A...604A..87G 2017A&A...604A..87G
Trifonov et al., 2018A&A...609A.117T 2018A&A...609A.117T, Cat. J/A+A/609/A117
Reiners et al., 2018A&A...609L...5R 2018A&A...609L...5R, Cat. J/A+A/609/L5
Reiners et al., 2018A&A...612A..49R 2018A&A...612A..49R, Cat. J/A+A/612/A49
Sarkis et al., 2018AJ....155..257S 2018AJ....155..257S
(End) Vera Maria Passegger [HS, Germany], Patricia Vannier [CDS] 29-Jun-2018