J/ApJ/683/424 CHARA observations of 3 late-type stars (Boyajian+, 2008)
Angular diameters of the G subdwarf µ Cassiopeiae A and the K dwarfs σ
Draconis and HR 511 from interferometric measurements with the CHARA array.
Boyajian T.S., McAlister H.A., Baines E.K., Gies D.R., Henry T., Jao W.-C.,
O'Brien D., Raghavan D., Touhami Y., ten Brummelaar T.A., Farrington C.,
Goldfinger P.J., Sturmann L., Sturmann J., Turner N.H., Ridgway S.
<Astrophys. J., 683, 424-432 (2008)>
=2008ApJ...683..424B 2008ApJ...683..424B
ADC_Keywords: Stars, late-type ; Interferometry
Keywords: infrared: stars - subdwarfs - techniques: interferometric -
stars: fundamental parameters (temperatures, diameters) -
stars: individual (HD 6582, HD 185144, HR 511, µ Cassiopeiae)
Abstract:
Using the longest baselines of the CHARA Array, we have measured the
angular diameter of the G5V subdwarf µ Cas A, the first such
determination for a halo population star. We compare this result to
new diameters for the higher metallicity K0V stars, σ Dra and HR
511, and find that the metal-poor star, µ Cas A, has an effective
temperature (Teff=5297±32K), radius (R=0.791±0.008R☉), and
absolute luminosity (L=0.442±0.014L☉) comparable to those of
the other two stars with later spectral types. We show that stellar
models show a discrepancy in the predicted temperature and radius for
µ Cas A, and we discuss these results and how they provide a key to
understanding the fundamental relationships for stars with low
metallicity.
Description:
Observations were taken using the CHARA Array, located on Mount
Wilson, CA, and remotely operated from the Georgia State University
AROC (Arrington Remote Operations Center) facility in Atlanta, GA.
Objects:
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RA (2000) DE Designation(s)
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01 08 16.4 +54 55 13 HR 321 = µ Cas A = HD 6582
01 47 44.8 +63 51 09 HR 511 = HD 10780 = V* V987 Cas
19 32 21.6 +69 39 40 HR 7462 = σ Dra = HD 185144
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 52 63 Interferometric measurements
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See also:
VI/46 : Second Catalog of Interferometric Measurements of Binary Stars
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- HR HR (Bright Star) number of star
6- 16 A11 --- Name Star name
18- 28 F11.3 d JD Julian Date of observation
30- 34 F5.1 m B Projected baseline
36- 40 F5.1 deg psi Orientation of the baseline on the sky
42- 46 F5.3 --- V Visibility (1)
48- 52 F5.3 --- e_V The 1σ error in V
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Note (1): Corrected for light from secondary for µ Cas A, see Section 3.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 01-Dec-2010