TY - JOUR
T1 - The size of AB Doradus A from VLTI/AMBER interferometry
AU - Guirado, J. C.
AU - Marcaide, J. M.
AU - Martí-Vidal, I.
AU - Le Bouquin, J. B.
AU - Close, L. M.
AU - Cotton, W. D.
AU - Montalbán, J.
N1 - Funding Information:
This work has been partially founded by grant AYA2009-13036-C02-02 of the Spanish MICINN, and by grant PROMETEO 104/2009 of the Generalitat Valenciana. The National Radio Astronomy Observatory is operated by Associated Universities, Inc. under cooperative agreement with the (US) National Science Foundation. This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France.
PY - 2011
Y1 - 2011
N2 - The pre-main sequence (PMS) star AB Dor A is the main component of the quadruple system AB Doradus. The precise determination of the mass and photometry of the close companion to AB Dor A, AB Dor C, has provided an important benchmark for calibration of theoretical evolutionary models of low-mass stars. The limiting factor to the precision of this calibration is the age of the system, as both the mass and luminosity of AB Dor A and C are well monitored by other ongoing programs. In this paper we present VLTI/AMBER observations of AB Dor A which provide a direct measurement of the size of this star, 0.96 ± 0.06 R±. The latter estimate, combined with other fundamental parameters also measured for this star, allows a precise test of PMS evolutionary models using both H-R diagrams and mass-radius relationships. We have found that our radius measurement is larger than that predicted by the models, which we interpret as an evidence of the oversizing produced by the strong magnetic activity of AB Dor A. Considering, at least partially, this magnetic effect, theoretical isochrones have been used to derive constraints to the age of AB Dor A, favouring an age about 40-50 Myr for this system. Older ages are not completely excluded by our data.
AB - The pre-main sequence (PMS) star AB Dor A is the main component of the quadruple system AB Doradus. The precise determination of the mass and photometry of the close companion to AB Dor A, AB Dor C, has provided an important benchmark for calibration of theoretical evolutionary models of low-mass stars. The limiting factor to the precision of this calibration is the age of the system, as both the mass and luminosity of AB Dor A and C are well monitored by other ongoing programs. In this paper we present VLTI/AMBER observations of AB Dor A which provide a direct measurement of the size of this star, 0.96 ± 0.06 R±. The latter estimate, combined with other fundamental parameters also measured for this star, allows a precise test of PMS evolutionary models using both H-R diagrams and mass-radius relationships. We have found that our radius measurement is larger than that predicted by the models, which we interpret as an evidence of the oversizing produced by the strong magnetic activity of AB Dor A. Considering, at least partially, this magnetic effect, theoretical isochrones have been used to derive constraints to the age of AB Dor A, favouring an age about 40-50 Myr for this system. Older ages are not completely excluded by our data.
KW - Stars: fundamental parameters
KW - Stars: individual: AB Doradus
KW - Stars: pre-main sequence
KW - Techniques: interferometric
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U2 - 10.1051/0004-6361/201117426
DO - 10.1051/0004-6361/201117426
M3 - Article
AN - SCOPUS:80052784029
VL - 533
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
SN - 0004-6361
M1 - A106
ER -