J/ApJ/746/101 Diameters and temperatures of AFG stars (Boyajian+, 2012)
Stellar diameters and temperatures.
I. Main-sequence A, F, and G stars.
Boyajian T.S., McAlister H.A., van Belle G., Gies D.R.,
ten Brummelaar T.A., von Braun K., Farrington C., Goldfinger P.J.,
O'Brien D., Parks J.R., Richardson N.D., Ridgway S., Schaefer G.,
Sturmann L., Sturmann J., Touhami Y., Turner N.H., White R.
<Astrophys. J., 746, 101 (2012)>
=2012ApJ...746..101B 2012ApJ...746..101B
ADC_Keywords: Stars, nearby ; Stars, diameters ; Interferometry ;
Infrared sources ; Photometry ; Effective temperatures
Keywords: Hertzsprung-Russell and C-M diagrams - infrared: stars -
stars: evolution - stars: fundamental parameters - stars: late-type -
stars: solar-type - techniques: interferometric
Abstract:
We have executed a survey of nearby, main-sequence A-, F-, and G-type
stars with the CHARA Array, successfully measuring the angular
diameters of forty-four stars with an average precision of ∼1.5%. We
present new measures of the bolometric flux, which in turn leads to an
empirical determination of the effective temperature for the stars
observed. In addition, these CHARA-determined temperatures, radii, and
luminosities are fit to Yonsei-Yale model isochrones to constrain the
masses and ages of the stars. These results are compared to indirect
estimates of these quantities obtained by collecting photometry of the
stars and applying them to model atmospheres and evolutionary
isochrones. We find that for most cases, the models overestimate the
effective temperature by ∼1.5%-4% when compared to our directly
measured values. The overestimated temperatures and underestimated
radii in these works appear to cause an additional offset in the
star's surface gravity measurements, which consequently yield higher
masses and younger ages, in particular for stars with masses greater
than ∼1.3 M☉. Additionally, we compare our measurements to a
large sample of eclipsing binary stars, and excellent agreement is
seen within both data sets. Finally, we present temperature relations
with respect to (B-V) and (V-K) colors as well as spectral type,
showing that calibration of effective temperatures with errors ∼1% is
now possible from interferometric angular diameters of stars.
Description:
The observations were made using the CHARA Array (optical/infrared
interferometric array) Classic beam combiner in two-telescope mode.
Nearly all (98.5%) of the observing for this work was performed
remotely from Georgia State University's Cleon Arrington Remote
Operations Center (AROC) in Atlanta, GA during the 2007, 2008, and
2009 observing seasons.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 110 44 Target sample of A, F, and G dwarfs
table5.dat 44 44 Angular diameters
table8.dat 145 3572 *Target photometry
table9.dat 46 44 Bolometric fluxes
table10.dat 40 44 Radii, luminosities, and temperatures
table12.dat 27 37 Y2 model isochrone results for stars with
L>0.75L☉
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Note on table8.dat: Values from Henry et al. (1984ApJ...280...98H 1984ApJ...280...98H) are not
magnitudes.
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See also:
V/130 : Geneva-Copenhagen Survey of Solar neighbourhood III (Holmberg+, 2009)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
IV/27 : HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index (Kostjuk, 2002)
J/ApJ/683/424 : CHARA observations of 3 late-type stars (Boyajian+, 2008)
J/ApJS/168/297 : Stellar parameters of nearby cool stars (Takeda+, 2007)
J/AJ/132/161 : NStars project: The southern sample. I. (Gray+, 2006)
J/PASJ/57/27 : Atmospheric parameters of nearby F-K stars (Takeda+, 2005)
J/ApJ/626/446 : Effective temperature scale of FGK stars (Ramirez+, 2005)
J/AJ/126/2048 : NStars project: the Northern Sample. I. (Gray+, 2003)
J/AJ/121/2159 : Basic parameters for 372 A, F + G stars (Gray+, 2001)
J/AJ/121/2148 : Precise spectral types for 372 A, F + G stars (Gray+, 2001)
J/PASP/110/863 : A Stellar Spectral Flux Library: 1150-25000Å (Pickles 1998)
J/A+AS/110/553 : Teff for B, A and F main sequence stars (Sokolov, 1995)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number
8- 11 I4 --- HR HR number
13- 18 I6 --- HIP HIP number
20- 33 A14 --- OName Other name (1)
35- 36 I2 h RAh Hour of right ascension (J2000)
38- 39 I2 min RAm Minute of right ascension (J2000)
41- 45 F5.2 s RAs Second of right ascension (J2000)
47 A1 --- DE- Sign of declination (J2000)
48- 49 I2 deg DEd Degree of declination (J2000)
51- 52 I2 arcmin DEm Arcminute of declination (J2000)
54- 58 F5.2 arcsec DEs Arcsecond of declination (J2000)
60- 69 A10 --- SpT MK spectral type (2)
71- 76 A6 --- SpT2 SIMBAD MK spectral type
78- 81 F4.2 mag Vmag [2.34,6.42] V-band magnitude
83- 86 F4.2 mag Kmag [2.02,4.38] K-band magnitude
88- 92 F5.3 mag (B-V) [0.014,0.804] B-V color index
94- 98 F5.2 [Sun] [Fe/H] [-1.36,0.33]? Metallicity (3)
100-105 F6.2 mas Plx [31.8,173.77] Parallax from van Leeuwen (2007,
Cat. I/311)
107-110 F4.2 mas e_Plx [0.12,0.85] Parallax uncertainty
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Note (1): Bayer-Flamsteed or GJ (Kostjuk 2004, Cat. IV/27).
Note (2): Gray et al. (2001, Cat. J/AJ/121/2148; 2003, Cat. J/AJ/126/2048)
Note (3): Holmberg et al. (2007, Cat. V/117; superseded by Cat. V/130), when
available. For stars without metallicity estimates from Holmberg et
al. (2007, Cat. V/117), the [M/H] values from Gray et al. (2003,
Cat. J/AJ/126/2048, 2006, Cat. J/AJ/132/161; HD 82885, HD 97603,
HD 118098, HD 131156, HD 177724, HD 210418), and Takeda et al. (2005,
Cat. J/PASJ/57/27; HD 182572) are used. Stars with no metallicity
measurements are HD 56537, HD 141795, and HD 213558.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number
8- 9 I2 --- Nobs [8,42] Number of observations
11- 14 F4.2 --- chi2 [0.08,2.23] Reduced χ2
16- 20 F5.3 mas D(UD) [0.6,1.6] Uniform disk diameter θUD
22- 26 F5.3 mas e_D(UD) [0.004,0.03] D(UD) uncertainty
28- 31 F4.2 --- muK [0.17,0.32] Limb-darkening coefficient µK
32 A1 --- --- [0]
34- 38 F5.3 mas D(LD) [0.6,1.7] Limb-darkened diameter θLD
40- 44 F5.3 mas e_D(LD) [0.004,0.03] D(LD) uncertainty
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HD]
4- 9 I6 --- HD Object HD identifier
11- 19 A9 nm Phot System or band wavelength (1030-3500[nm],
Geneva, Johnson or Stromgren) (1)
21- 23 A3 --- Band Filter or bandwidth (206-700nm, B, B1, B2, G
or H) (1)
25- 29 F5.2 mag mag [0.37/53.2] Observed magnitude in Band (1)
31- 34 F4.2 mag e_mag [0.04/5.32] Error in mag (1)
36- 62 A27 --- Aut Author's name for the reference
64-145 A82 --- BibCode Bibcode or complete reference
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Note (1): See Section 2.3 for details of the calibration.
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number
8- 13 A6 --- SpT3 Template MK spectral type (4)
15- 17 I3 --- Nph [69,279] Number of photometry points
19- 22 F4.2 --- chi2P [0.25,3.85] Reduced χ2
24- 29 F6.2 10-11W/m2 Fbol [8.27,339.9] Integrated bolometric flux in
units of 10-8erg/s/cm2
31- 34 F4.2 10-11W/m2 e_Fbol [0.08,7.05] Fbol uncertainty
36- 40 F5.3 mag Av [0,0.062] Extinction
42- 46 F5.3 mag e_Av [0.008,0.023] Av uncertainty
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Note (4): Pickles (1998, Cat. J/PASP/110/863) template spectral type.
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number
8- 12 F5.3 Rsun R [0.681,3.021] Stellar radius
14- 18 F5.3 Rsun e_R [0.004,0.083] R uncertainty
20- 25 F6.3 Lsun L [0.212,63.015] Stellar luminosity
27- 31 F5.3 Lsun e_L [0.002,1.307] L uncertainty
33- 36 I4 K Teff [4759,9377] Effective temperature
38- 40 I3 K e_Teff [19,167] Teff uncertainty
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Byte-by-byte Description of file: table12.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number
8- 12 F5.3 Msun M [0.852,2.209] Stellar mass
14- 18 F5.3 Msun e_M [0.005,0.095] M uncertainty
20- 23 F4.1 Gyr Age [0.2,14.9] Stellar age
25- 27 F3.1 Gyr e_Age [0,3.1] Age uncertainty
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History:
From electronic version of the journal
References:
Boyajian et al. Paper II. 2012ApJ...757..112B 2012ApJ...757..112B
Boyajian et al. Paper III. 2013ApJ...771...40B 2013ApJ...771...40B
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 07-Aug-2013