J/A+A/526/A99 Metal-poor solar-type stars spectroscopy and masses (Sousa+, 2011)
Spectroscopic characterization of a sample of metal-poor solar-type stars from
the HARPS planet search program.
Precise spectroscopic parameters and mass estimation.
Sousa S.G., Santos N.C., Israelian G., Lovis C., Mayor M., Silva P.B.,
Udry S.
<Astron. Astrophys. 526, A99 (2011)>
=2011A&A...526A..99S 2011A&A...526A..99S
ADC_Keywords: Stars, nearby ; Spectroscopy ; Parallaxes, trigonometric ;
Photometry ; Stars, masses
Keywords: stars: fundamental parameters - planetary systems -
stars: abundances - stars: statistics
Abstract:
Stellar metallicity strongly correlates with the presence of planets
and their properties. To check for new correlations between stars and
the existence of an orbiting planet, we determine precise stellar
parameters for a sample of metal-poor solar-type stars. This sample
was observed with the HARPS spectrograph and is part of a program to
search for new extrasolar planets.
Description:
The stellar parameters were determined using an LTE analysis based on
equivalent widths (EW) of iron lines and by imposing excitation and
ionization equilibrium. The ARES code (that can be downloaded at
http://www.astro.up.pt/~sousasag/ares ) was used to allow automatic
and systematic derivation of the stellar parameters. Precise stellar
parameters and metallicities were obtained for 97 low metal-content
stars. We also present the derived masses, luminosities, and new
parallaxes estimations based on the derived parameters, and compare
our spectroscopic parameters with an infra-red flux method calibration
to check the consistency of our method in metal poor stars. Both
methods seems to give the same effective temperature scale.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 38 104 Details of the spectral data for each star
table2.dat 94 97 Stellar parameters for the metal poor sample
table3.dat 78 103 Photometry used for the use of IFRM calibration
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
I/297 : NOMAD Catalog (Zacharias+ 2005)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
V/109 : SKY2000 Catalog, Version 4 (Myers+ 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Star's identifier
12- 13 I2 --- Nsp Total number of spectra observed
15- 16 I2 --- Ncsp Number of combined spectra
18- 23 F6.2 --- S/Nh Highest S/N value from the combined spectrum
25- 30 F6.2 --- S/Nl Lowest S/N value from the combined spectrum
32- 38 F7.2 --- S/N Final S/N for the combined spectrum
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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 Star's identifier
12- 15 I4 K Teff Effective temperature
17- 19 I3 K e_Teff Error on Teff
21- 24 F4.2 [cm/s2] logg Spectroscopic surface gravity
26- 29 F4.2 [cm/s2] e_logg Error on logg
31- 34 F4.2 km/s xi Microturbulence velocity
36- 39 F4.2 km/s e_xi Error on Vtur
41- 45 F5.2 [Sun] [Fe/H] Iron abundance [Fe//H]
47- 50 F4.2 [Sun] e_[Fe/H] Error on [Fe//H]
52- 54 I3 --- NFe1 Number of FeI lines used
56- 57 I2 --- NFe2 Number of FeII lines used
59- 62 F4.2 Msun M.HIP ?=- Stellar mass determined directly from
Padova webinterface using Hipparcos parallax
64- 67 F4.2 Msun e_M.HIP ? Error on M.HIP
69- 72 F4.2 Msun Mass ?=- Estimation of the stellar mass using
iterative procedure to compute new parallax
values
74- 77 F4.2 Msun e_Mass ? Error on Mass
79- 83 F5.2 mas plxH ?=- Hipparcos parallax
85- 88 F4.2 mas e_plxH ? Error on Hipparcos parallax
90- 94 F5.2 mas plx ?=- Estimated parallax from iterative procedure
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Star's identifier
11- 15 F5.2 mag Umag ?=- SKY2000 U magnitude (1)
17- 22 F6.3 mag Bmag ?=- NOMAD B magnitude (2)
24- 29 F6.3 mag Vmag NOMAD V magnitude (2)
30 A1 --- n_Vmag [*] * for Vmag from HIP catalog
31- 36 F6.3 mag Imag ?=- NOMAD I magnitude (2)
38- 42 F5.3 mag V-I ?=- HIP V-I color index (3)
44- 48 F5.3 mag Jmag ?=- 2MASS J magnitude (4)
50- 54 F5.3 mag Hmag ?=- 2MASS H magnitude (4)
56- 60 F5.3 mag Kmag ?=- 2MASS K magnitude (4)
62- 66 F5.3 mag e_Jmag ?=- Error on J magnitude
68- 72 F5.3 mag e_Hmag ?=- Error on H magnitude
74- 78 F5.3 mag e_Kmag ?=- Error on K magnitude
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Note (1): from the SKY2000 Catalog, Version 4 (Myers et al., 2001, Cat. V/109)
Note (2): were obtained from the NOMAD catalog (Zacharias et al. 2004,
Cat. I/297)
Note (3): from the index V-I obtained in the Hipparcos catalog
(van Leeuwen, 2007, Cat. I/311)
Note (4): were obtained from the 2MASS catalog (Cutri et al. 2003, Cat. II/246/)
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Acknowledgements:
Sergio G. Sousa, sousasag(at)astro.up.pt
(End) Sergio G. Sousa [CAUP-Porto, Portugal], Patricia Vannier [CDS] 04-Jan-2011