J/ApJ/858/71 CHARA array obs. of 13 AB Dor moving group stars (Schaefer+, 2018)
AB Dor moving group stars resolved with the CHARA array.
Schaefer G.H., White R.J., Baines E.K., Boyajian T.S., Brummelaar T.A.t.,
Farrington C.D., Sturmann J., Sturmann L., Turner N.H.
<Astrophys. J., 858, 71 (2018)>
=2018ApJ...858...71S 2018ApJ...858...71S
ADC_Keywords: Interferometry; Infrared sources; YSOs
Keywords: stars: fundamental parameters;
stars: individual (GJ 159, GJ 393, HD 89744);
stars: pre-main sequence; techniques: interferometric
Abstract:
We present interferometric measurements obtained with the CHARA Array
of 13 adolescent-age stars in nearby moving groups. The motivation was
to spatially resolve the largest stars and to search for binary
companions. Nine stars have diameters smaller than the resolution
limit and no evidence for companions within 0.5-50mas and ΔH<2.0mag.
The diameters of three stars were spatially resolved: GJ 159
(0.582±0.016mas) and GJ 393 (0.564±0.021mas) in the AB Dor moving
group, and former member HD 89744 (0.556±0.032mas). Combining the
angular diameters with their distances and bolometric fluxes, we
measured radii and effective temperatures. The temperatures of GJ 159
(6286±123K) and GJ 393 (3515±68K) are consistent with spectroscopic
measurements. Comparisons with evolutionary models show that HD 89744
has evolved off the main sequence. GJ 159 and GJ 393 lie within
1.5σ of the zero-age main sequence, complicating their age
estimates because it is unclear whether the stars are contracting or
expanding. GJ 159 has a mass of 1.2±0.1M☉ with an age spanning
0.021-3.0Gyr. Its debris disk and lithium abundance favor a young age.
GJ 393 has a mass of 0.42±0.03M☉ and a lower limit on its age
0.06Gyr. This overlaps with the age of the moving group; however, an
older age would be more consistent with its slow rotation, low
activity, and luminosity, suggesting that GJ 393 is a kinematic
interloper.
Description:
The CHARA Array is an optical/infrared interferometer consisting of
six 1m telescopes arranged in a Y-configuration with baselines ranging
from 34 to 331m. We observed the 13 young stars in our sample using
the CHARA Classic beam combiner.
Observations (between 2007 and 2010) were obtained in both the H-band
(1.6731um center, 0.2854um width) and K'-band (2.1329um center,
0.3489um width). To achieve the highest possible spatial resolution,
we used the longest 331m baseline between the S1 and E1 telescopes.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 76 13 Observed sample of stars
table3.dat 84 138 CHARA-classic observations of young stars in AB Dor
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See also:
B/wds : The Washington Visual Double Star Catalog (Mason+ 2001-2014)
III/119 : Spectral classifications of proper motion stars (Bidelman+ 1985)
III/218 : ELODIE archive (Prugniel+, 2001)
V/136 : Teff and metallicities for Tycho-2 stars (Ammons+, 2006)
J/A+A/275/101 : Chemical evolution of the gal. disk I. (Edvardsson+ 1993)
J/A+A/314/191 : Atmospheric param. in metal-poor stars. I (Gratton+, 1996)
J/PASP/110/863 : A Stellar Spectral Flux Library: 1150-25000AA (Pickles 1998)
J/A+AS/141/491 : Chemical composition of halo and disk stars (Nissen+, 2000)
J/AJ/126/2048 : NStars project: the Northern Sample. I. (Gray+, 2003)
J/ApJ/593/1093 : IC 348 membership (Luhman+, 2003)
J/A+A/415/1153 : [Fe/H] for 98 extra-solar planet-host stars (Santos+, 2004)
J/other/ARA+A/42.685 : Young stars near the Sun (Zuckerman+, 2004)
J/ApJ/626/446 : Effective temperature scale of FGK stars (Ramirez+, 2005)
J/PASJ/57/27 : Atmospheric parameters of nearby F-K stars (Takeda+, 2005)
J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)
J/A+A/433/151 : Spectrosc. result on ROSAT late-type stars (Zickgraf+, 2005)
J/A+A/450/735 : Effective temperatures and radii of stars (Masana+, 2006)
J/A+A/446/267 : Stellar latitudinal differential rotation (Reiners+, 2006)
J/MNRAS/378/1141 : Abundances in 31 stars with planet (Gonzalez+, 2007)
J/AJ/134/1671 : Speckle interferometry at USNO. XIII (Mason+, 2007)
J/ApJS/171/146 : Population synthesis in the blue. IV (Schiavon+, 2007)
J/ApJS/172/663 : Infrared observations of the Pleiades (Stauffer+, 2007)
J/ApJ/683/424 : CHARA observations of 3 late-type stars (Boyajian+, 2008)
J/MNRAS/389/585 : Fundamental parameters of M dwarfs (Casagrande+, 2008)
J/A+A/508/833 : SACY III. Li abundances (da Silva+, 2009)
J/AJ/137/4186 : UBVRI standards around celestial equator (Landolt, 2009)
J/A+A/493/1099 : CaIIHK emission in rapidly rotating stars (Schroeder+, 2009)
J/MNRAS/403/1368 : Li abundances & vsini for star-planet syst (Gonzalez+, 2010)
J/MNRAS/403/1949 : UBV(RcIc)JHK photometry of HIP nearby stars (Koen+, 2010)
J/AJ/140/119 : βPic & AB Dor moving groups members (Schlieder+, 2010)
J/other/A+ARV/18.67 : Accurate masses & radii of normal stars (Torres+, 2010)
J/MNRAS/411/435 : Stellar parameters and extinction (Bailer-Jones, 2011)
J/A+A/530/A138 : Geneva-Copenhagen survey re-analysis (Casagrande+, 2011)
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/AJ/141/90 : SEGUE stellar parameter pipeline. V. (Lee+, 2011)
J/A+A/531/A165 : MILES atmospheric parameters (Prugniel+, 2011)
J/ApJ/732/55 : Abundances of stars with planets (Schuler+, 2011)
J/A+A/525/A71 : Atmospheric parameters for 1273 stars (Wu+, 2011)
J/MNRAS/424/3178 : Pre-main-sequence isochrones. Pleiades (Bell+, 2012)
J/ApJ/746/101 : Diameters and temperatures of AFG stars (Boyajian+, 2012)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/AJ/143/134 : Cand. members of β Pic/AB Dor groups (McCarthy+, 2012)
J/ApJ/745/24 : A search for new companions with CHARA (Raghavan+, 2012)
J/ApJ/756/46 : Lithium abundances in HIP stars (Ramirez+, 2012)
J/A+A/553/A95 : PCA approach to stellar effective temp. (Bermejo+, 2013)
J/A+A/549/A109 : HARPS XXXI. The M-dwarf sample (Bonfils+, 2013)
J/ApJ/771/40 : Main-sequence A, F, G, K stars photometry (Boyajian+, 2013)
J/A+A/552/A6 : Abundances of F-G stars (Gonzalez Hernandez+, 2013)
J/AJ/145/102 : Bright M dwarfs spec. in the northern sky (Lepine+, 2013)
J/ApJ/762/88 : Young stellar kinematic group cand. members (Malo+, 2013)
J/ApJ/779/188 : Spectra of nearby late K and M Kepler stars (Mann+, 2013)
J/A+A/557/A70 : Evolved planet hosts - stellar parameters (Mortier+, 2013)
J/A+A/551/A36 : Metallicity of M dwarfs. III. (Neves+, 2013)
J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)
J/A+A/556/A15 : Effective temperature scale of M dwarfs (Rajpurohit+, 2013)
J/MNRAS/435/952 : Lick indices for 51 stars (Sansom+, 2013)
J/MNRAS/431/2063 : UV/X-ray activity of M dwarfs within 10pc (Stelzer+, 2013)
J/A+A/568/A26 : SACY. V. Multiple systems (Elliott+, 2014)
J/ApJ/791/54 : Nearby M Dwarfs parameters (Gaidos+, 2014)
J/AJ/147/20 : Spectroscopy of 447 nearby M dwarfs (Newton+, 2014)
J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)
J/A+A/577/A132 : Stellar parameters of early M dwarfs (Maldonado+, 2015)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/ApJ/800/85 : Teff, radii and luminosities of cool dwarfs (Newton+, 2015)
J/ApJS/220/16 : SpeX NIR survey of 886 nearby M dwarfs (Terrien+, 2015)
J/A+A/585/A5 : Exoplanet host/field stars age consistency (Bonfanti+, 2016)
J/A+A/586/A94 : Exoplanetary parameters for 18 bright stars (Ligi+, 2016)
J/AJ/153/95 : Catalog of Suspected Nearby Young Stars (Riedel+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Star name (as used in Table 3)
12- 21 A10 --- OName Other name
23- 28 A6 --- HD HD number
30- 35 I6 --- HIP [10272/106231]? HIP number
37- 44 A8 --- Group Moving group identification
45 A1 --- f_Group [n] n: the star is no longer considered
to be a member
47- 50 A4 --- SpT MK spectral type (1)
51 A1 --- u_SpT [*] Uncertainty flag on SpT (2)
53- 57 F5.2 pc Dist [7/49.2] Distance (3)
59- 62 F4.2 pc e_Dist [0.1/4.4]? Dist uncertainty (3)
64- 69 F6.3 mag Vmag [5.3/10.3]? V-band magnitude (4)
70 A1 --- u_Vmag [*] Uncertainty flag on Vmag (2)
72- 75 F4.2 --- Ksmag [4/7] 2MASS Ks band magnitude
76 A1 --- u_Ksmag [*] Uncertainty flag on Ksmag (2)
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Note (1): The spectral types are from either the spectroscopic study of
McCarthy & White (2012, J/AJ/143/134) or the original membership
survey (Zuckerman & Song 2004, J/other/ARA+A/42.685 ;
Lopez-Santiago+ 2006ApJ...643.1160L 2006ApJ...643.1160L).
Note (2): Values marked with an asterisk indicate measurements that may be
biased by a spatially unresolved companion.
Note (3): Distances given with uncertainties are calculated from Hipparcos
parallax measurements, while those without are kinematically
estimated by Torres+ (2008hsf2.book..757T 2008hsf2.book..757T).
Note (4): The V-band magnitudes are calculated from VT magnitudes in the
Tycho-2 Catalog (Hog+ 2000, I/259), using the prescription of
Bessell (2000PASP..112..961B 2000PASP..112..961B).
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Name Star name
14- 24 A11 "Y/M/D" Date UT date of the observation
26- 35 F10.4 d MJD [54418.4/55293.5] Observation date;
modified Julian Date
37- 41 A5 --- Baseline Baseline description
43- 48 F6.4 um lambda [1.6/2.2] Wavelength observed
50- 55 F6.2 10+6/rad u [-95.1/125] u Coordinate;
106cycles/radian
57- 62 F6.2 10+6/rad v [-86/194] v Coordinate;
106cycles/radian
64- 69 F6.2 m EBL [207/331] Effective baseline length
71- 75 F5.3 --- Vis [0.6/1.3] Visibility
77- 82 F6.4 --- e_Vis [0.01/0.4] Uncertainty in Visibility
84 A1 --- f_Vis Visibility flag (1)
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Note (1): Visibility flags as follows:
a = The visibility uncertainties for the three resolved stars have been
scaled to force χ2ν=1 for the best fit limb-darkened model.
The visibilities for the unresolved stars and the PX Vir binary are
available online (the uncertainties for the unresolved targets have
not been scaled).
b = The visibilities for HD 13482 have been corrected for the presence
of incoherent light from the binary companion (see Section 2.4).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Mar-2019