J/ApJ/873/91 Interferometric obs. of B-type stars with CHARA (Gordon+, 2019)
Angular sizes, radii, and effective temperatures of B-type stars from optical
interferometry with the CHARA Array.
Gordon K.D., Gies D.R., Schaefer G.H., Huber D., Ireland M.
<Astrophys. J., 873, 91 (2019)>
=2019ApJ...873...91G 2019ApJ...873...91G
ADC_Keywords: Interferometry; Stars, B-type; Effective temperatures;
Stars, distances; Stars, diameters; Reddening
Keywords: stars: early-type ; stars: fundamental parameters ; stars: massive ;
techniques: interferometric
Abstract:
We present interferometric observations of 25 spectral type-B stars
that were made with the Precision Astronomical Visible Observations
and the CLassic Interferometry with Multiple Baselines beam combiners
at the Center for High Angular Resolution Astronomy Array (CHARA). The
observations provide the angular sizes of these stars with an average
error of 6%. The stars range in size from 1.09mas for β Tau down
to 0.20mas for 32 Ori. We collected ultraviolet to infrared
spectrophotometry and derived temperatures, angular diameters, and
reddening estimates that best fit the spectra, as well as solutions
with the angular size fixed by the interferometric measurements. There
is generally good agreement between the observed and spectral fit
angular diameters, indicating that the fluxes predicted from model
atmospheres are reliable. On the other hand, the temperatures derived
from angular diameters and fluxes tend to be larger (by ∼4%) than
those from published results based on analysis of the line spectrum.
This discrepancy may in part be attributed to unexplored atmospheric
parameters or the existence of unknown companions. The physical radii
of the stars are calculated from the angular diameters and Gaia DR2
parallaxes, and the target stars are placed in the Hertzsprung-Russell
diagram for comparison with evolutionary tracks.
Description:
Our sample consists of 25 B-type stars with spectral types ranging
from B2 to B9.5. All luminosity classes are represented with one
supergiant, 14 giants, and 10 main-sequence stars.
Observations of our targets were made using the Precision Astronomical
Visible Observations (PAVO) beam combiner and the CLassic
Interferometry with Multiple Baselines (CLIMB) beam combiner at the
Center for High Angular Resolution Astronomy Array (CHARA), located at
Mount Wilson Observatory in California.
Observations with the CHARA Array were accomplished from 2012
September to 2017 June over a total of 28 nights of observation.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 70 25 Parameters of sample stars
table4.dat 113 1937 Calibrated visibilities
table5.dat 64 25 Observations and measured angular diameters
table6.dat 74 25 Comparison of observed and literature angular
diameter measurements
table7.dat 50 25 Temperature and reddening estimates
table8.dat 51 25 Distance and radius estimates
--------------------------------------------------------------------------------
See also:
B/pastel : The PASTEL catalogue (Soubiran+, 2016-)
II/62 : Catalogue of Extinction Data (Neckel+, 1980)
II/114 : UV Interstellar Extinction (Savage+ 1985)
III/196 : NIR stellar spectra from 1.428 to 2.5 um (Lancon+ 1996)
III/201 : Pulkovo Spectrophotometric Catalog (Alekseeva+ 1997)
II/224 : Catalog of Stellar Diameters (CADARS) (Pasinetti-Fracassini+ 2001)
III/218 : ELODIE archive (Prugniel+, 2001)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
III/232 : STELIB: A library of stellar spectra at R∼2000 (Le Borgne+, 2003)
III/244 : Catalog of Stellar Rotational Velocities (Glebocki+ 2005)
I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007)
II/346 : JMMC Stellar Diameters Catalogue - JSDC. Version 2 (Bourges+, 2017)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/AJ/117/548 : 1997 WIYN binary stars speckle observations (Horch+, 1999)
J/AJ/119/3084 : ICCD speckle obs. of binary stars. XXIII. (Hartkopf+, 2000)
J/MNRAS/326/959 : Empirical calibration of the NIR Ca triplet (Cenarro+ 2001)
J/ApJS/152/251 : Library of coude feed stellar spectra (Valdes+, 2004)
J/AJ/129/1642 : Calibration of synthetic photometry (Fitzpatrick+, 2005)
J/A+A/447/685 : Elemental abundance analyses. XXIX. (Adelman+, 2006)
J/other/AstBu/62.339 : Speckle interferometry of nearby mult. (Balega+, 2007)
J/MNRAS/374/664 : Stellar atmospheric param. in MILES library (Cenarro+, 2007)
J/ApJ/683/424 : CHARA observations of 3 late-type stars (Boyajian+, 2008)
J/MNRAS/399/2146 : Orbits of open clusters in the Galaxy (Wu+, 2009)
J/A+A/501/297 : Effective temperatures of B Supergiants (Zorec+, 2009)
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/MNRAS/454/28 : Bayesian statistics for massive stars (Mugnes+, 2015)
J/AJ/152/40 : Spectroscopy of bright A- & B-type stars (Gullikson+, 2016)
J/AJ/152/213 : Interferometry & spectroscopy of sigma Ori (Schaefer+, 2016)
J/AJ/153/16 : Calibrator stars for interferometers (Swihart+, 2017)
J/AJ/155/30 : Fundamental param. of 87 stars from the NPOI (Baines+, 2018)
J/ApJ/869/37 : Optical interferometry of 6 O-type HD stars (Gordon+, 2018)
J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/25] Running sequence number
4- 15 A12 --- Name Star Name
17- 22 I6 --- HD [2772/222661] HD Number
24- 30 A7 --- SpT SIMBAD spectral type
32- 35 F4.2 mag Vmag [1.65/4.84] SIMBAD V band magnitude
37- 41 F5.2 mag B-V [-0.22/0.42] B-V color index from SIMBAD
43- 47 F5.2 mag V-K [-0.73/1.11] V-K color index from SIMBAD
49- 52 F4.1 kK Teff [10.0/26.8] Surface effective temperature (1)
54- 56 F3.1 kK e_Teff [0.1/1.0] Uncertainty in Teff
58- 61 F4.2 [cm/s2] logg [2.1/4.5] log, surface gravity (1)
63- 66 F4.2 [cm/s2] e_logg [0.03/0.25] Uncertainty in logg
68- 70 I3 km/s vsini [10/220] Projected rotational velocity (2)
--------------------------------------------------------------------------------
Note (1): Effective temperatures and gravities are average values taken
from several sources:
the PASTEL catalog (Soubiran+ 2016, B/pastel), the ELODIE archive
(Prugniel & Soubiran 2001, III/251), the Indo-US Library (Valdes+, 2004,
J/ApJS/152/251), the STELIB library (Le Borgne+ 2003, III/232), the
MILES library (Cenarro+ 2007, J/MNRAS/374/664),
Cenarro+ (2001, J/MNRAS/326/959), Gullikson+ (2016, J/AJ/152/40),
Kraus+ (2015A&A...581A..75K 2015A&A...581A..75K), Lyubimkov+ (2004MNRAS.351..745L 2004MNRAS.351..745L),
Morales+ (2001ApJ...552..278M 2001ApJ...552..278M), and Zorec+ (2009, J/A+A/501/297).
Note (2): The projected rotational velocity vsini values are from Catalog
of Stellar Rotational Velocities, Glebocki & Gnacinski (2005ESASP.560..571G 2005ESASP.560..571G
-- III/244).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Beam CHARA Beam combiner, PAVO or CLIMB
7- 12 I6 --- HD [2772/222661] HD Number
14- 18 I5 d MJD [56214/57573] Modified Julian Date
of observation (JD-2400000.5)
20- 25 A6 --- Tel Array telescope pair
27- 35 F9.5 10-6rad-1 spatial [114.4/505.7] Frequency of the observation
37- 45 F9.3 arcsec-1 u [-2254/2252] u position of spatial frequency
47- 56 F10.4 arcsec-1 v [-2302/2126] v position of spatial frequency
58- 64 F7.3 m B [140.7/330.7] Baseline
66- 78 F13.10 --- V2 [-5.61e-5/0.9] Visibility, squared
80- 91 F12.9 --- e_V2 [-0.002/0.4] Uncertainty in V2
93-102 F10.8 --- V2c [0.008/1]? Visibility, squared and corrected
for companion flux
104-113 F10.8 --- e_V2c [0.003/0.4]? Uncertainty in V2c
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- HD [2772/222661] HD Number
8- 8 A1 --- Beam [PC] CHARA Beam combiner, (P)AVO or (C)LIMB
10- 18 A9 --- Bl Baseline(s)
20- 22 I3 --- NV2 [6/312] Number of visibilities in calculation
24- 28 F5.3 mas ThetaUD [0.19/1.1] Uniform disk diameter
30- 34 F5.3 mas e_ThetaUD [0.01/0.08] Uncertainty in ThetaUD (3)
36- 39 F4.2 --- muR [0.2/0.4]? R-band linear limb darkening
coefficient
41- 44 F4.2 --- muH [0.16/0.18]? H-band linear limb darkening
coefficient
46- 50 F5.3 mas ThetaLD [0.2/1.1] Limb-darkened disk diameter
52- 56 F5.3 mas e_ThetaLD [0.01/0.08] Uncertainty in ThetaLD (3)
58- 59 A2 --- f_ThetaLD Flag on Theta-LD (G1)
61- 64 F4.2 --- Ratio [0.3/1.1] Maximum, Theta-cal / ThetaLD ratio
--------------------------------------------------------------------------------
Note (3): Errors associated with the angular diameters were calculated from
two or three components: 1) uncertainty associated with the angular
diameter based upon the size of the residuals to the fit 2) reflects the
night-to-night variations in the derived stellar angular diameter; 3)
uncertainty due to the error in the assumed calibrator size.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- HD [2772/222661] HD Number
8- 12 F5.3 mas ThetaLD1 [0.2/1.09] Limb-darkened diameter, this work
14- 18 F5.3 mas e_ThetaLD1 [0.015/0.08] Uncertainty in ThetaLD1
20- 21 A2 --- f_ThetaLD1 Flag on Theta-LD1 (G1)
23- 27 F5.3 mas ThetaLD2 [0.09/1.16]? Limb-darkened diameter
from JSDC V2 ( Bourges+ 2014, II/346)
29- 33 F5.3 mas e_ThetaLD2 [0.003/0.1]? Uncertainty in ThetaLD2
35- 39 F5.3 mas ThetaLD3 [0.3/1.1]? Limb-darkened diameter
from Underhill+ (1979MNRAS.189..601U 1979MNRAS.189..601U)
41- 45 F5.3 mas e_ThetaLD3 [0.001/0.01]? Uncertainty in ThetaLD3
47- 50 F4.2 mas ThetaLD4 [0.27/1.1] Limb-darkened diameter
from CADARS (Pasinetti Fracassini+,
2011, II/224)
52- 56 F5.3 mas ThetaLD5 [0.3/1]? Limb-darkened diameter
from Swihart+ (2017, J/AJ/153/16)
58- 62 F5.3 mas e_ThetaLD5 [0.013/0.15]? Uncertainty in ThetaLD5
64- 68 F5.3 mas ThetaLD6 [0.2/1.2] Limb-darkened diameter from SED (4)
70- 74 F5.3 mas e_ThetaLD6 [0.005/0.2] Uncertainty in ThetaLD6
--------------------------------------------------------------------------------
Note (4): Angular diameter associated with the global minimum of χ2-ν
of the model fit of the SED.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- HD [2772/222661] HD Number
8- 11 F4.1 kK Teff1 [10/29.5]? Derived Teff,
this work from Theta-LD
13- 15 F3.1 kK e_Teff1 [0.3/2.5]? Uncertainty in Teff1
17- 18 A2 --- f_Teff1 Flag on Teff1 (G1)
20- 23 F4.1 kK TeffSED [9.5/23.6] Teff derived from SED
25- 27 F3.1 kK e_TeffSED [0.3/1.3] Uncertainty in TeffSED
29- 32 F4.1 kK TeffLit [10/26.8] Literature Teff
34- 36 F3.1 kK e_TeffLit [0.1/1] Uncertainty in TeffLit
38- 42 F5.3 mag E(B-V)1 [0.007/0.7]? Best Fit E(B-V), this work
44- 45 A2 --- f_E(B-V)1 Flag on E(B-V)1 (G1)
47- 50 F4.2 mag E(B-V)Lit [0.01/0.6] Literature E(B-V) (5)
--------------------------------------------------------------------------------
Note (5): Literature E(B-V) values are the average from Neckel+ (1980, II/62)
and Savage+ (1985, II/114).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- HD [2772/222661] HD Number
8- 11 I4 pc Dist1 [37/1072]? Literature distance
from Underhill+ (1979MNRAS.189..601U 1979MNRAS.189..601U)
13- 17 F5.1 pc Dist2 [31.9/714.3] Literature distance
from van Leeuwen (2007, I/311) and M
Maiz Apellaniz+ (2008arXiv0804.2553M 2008arXiv0804.2553M)
19- 22 F4.1 pc e_Dist2 [0.2/86.7] Uncertainty in Dist2
24- 29 F6.1 pc Dist3 [37.0/1177.0]? Gaia DR2 (I/345) distance
31- 35 F5.1 pc e_Dist3 [0.7/186.8]? Uncertainty in Dist2
37- 41 F5.2 Rsun Rstar [1.82/56.7] Derived stellar radii (6)
43- 46 F4.2 Rsun e_Rstar [0.1/9.46] Uncertainty in Rstar
48- 48 A1 --- Bin [*] *: stars with close companions
50- 51 A2 --- f_Rstar Flag on Rstar (G1)
--------------------------------------------------------------------------------
Note (6): Stellar radii are calculated from the Gaia DR2 parallaxes where
available; Hipparcos parallaxes were adopted if no Gaia DR2 parallax was
available.
--------------------------------------------------------------------------------
Global notes:
Note (G1): Flag as follows:
dg = indicates results we consider preliminary for reasons discussed
in Section 4.2.
--------------------------------------------------------------------------------
Acknowledgements:
Kathryn D. Gordon [Georgia State University]
History:
From electronic version of the journal
Table 4, data for HD 177756 sent by the author.
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 13-Aug-2020