J/AJ/156/27 Masses & radii of 4 VLM stars in EB systems (Chaturvedi+, 2018)
Masses and radii of four very low-mass stars in F+M eclipsing binary systems.
Chaturvedi P., Sharma R., Chakraborty A., Anandarao B.G., Prasad N.J.S.S.V.
<Astron. J., 156, 27-27 (2018)>
=2018AJ....156...27C 2018AJ....156...27C (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Stars, F-type ; Stars, dwarfs ;
Stars, M-type ; Radial velocities ; Stars, masses ;
Stars, diameters
Keywords: stars: individual: SAO 106989, HD 24465, EPIC 211682657, HD 205403 -
stars: low-mass - techniques: radial velocities
Abstract:
Eclipsing binaries (EBs) with one of the companions as very low-mass
stars (VLMSs; or M dwarfs) are testbeds to substantiate stellar models
and evolutionary theories. Here we present four EB candidates with F-type
primaries, namely, SAO 106989, HD 24465, EPIC 211682657, and HD 205403,
identified from different photometry missions, SuperWASP, Kilodegree
Extremely Little Telescope (KELT), Kepler 2 (K2), and Solar Terrestrial
Relations Observatory (STEREO). Using the high-resolution spectrograph
PRL Advanced Radial velocity Abu-sky Search at the 1.2 m telescope at
Mount Abu, Rajasthan, India, we hereby report the detection of four VLMSs
as companions to the four EBs. We performed spectroscopic analysis and
found the companion masses to be 0.256±0.005, 0.233±0.002,
0.599±0.017, and 0.406±0.005 M☉ for SAO 106989, HD 24465,
EPIC 211682657, and SAO 106989B, respectively. We determined orbital
periods of 4.39790±0.00001, 7.19635±0.00002, 3.142023±0.000003,
and 2.444949±0.000001 days and eccentricities of 0.248±0.005,
0.208±0.002, 0.0097± 0.0008, and 0.002±0.002 for EBs SAO 106989,
HD 24465, EPIC 211682657, and HD 205403, respectively. The radii derived
by modeling the photometry data are 0.326±0.012 R☉ for SAO 106989,
0.244±0.001 R☉ for HD 24465B, 0.566±0.005 R☉ for
EPIC 211682657B, and 0.444±0.014 R☉ for HD 205403B. The radii
of HD 24465B and EPIC 211682657B have been measured by precise Kepler
photometry and are consistent with theory within the error bars. However,
the radii of SAO 106989B and HD 205403B, measured by KELT and STEREO
photometry, are 17%-20% higher than those predicted by theory. A brief
comparison of the results of the current work is made with the M dwarfs
already studied in the literature.
Description:
Selection of EB candidates involved choosing stars brighter than ∼11
in the V band, as it is the faintest limit for PARAS with the 1.2 m
telescope. Spectral types from F to K were chosen, as these stars have
more spectral lines for precise RV measurements. High-resolution
spectroscopic observations of the program EBs were taken during 2013-2017
using the optical fiber-fed echelle spectrograph PARAS (high-resolution,
R∼67000, cross-dispersed spectrograph) coupled with the 1.2 m telescope
at Gurushikhar, Mount Abu, India. The spectrograph has a spectral coverage
of 3800-9000 Å. However, for precise RV measurements, a wavelength
range of 3800-6800 Å is utilized.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 56 4 List of stars
table1.dat 56 70 RV observations for all stars: SAO 106989,
HD 24465, EPIC 211682657 and HD 205403
table4.dat 63 90 A compilation of known M dwarfs (M=<0.6 M☉)
from the literature which have masses and radii
measured at accuracies better than or at best
equal to 10%
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See also:
J/A+A/364/665 : Very low mass stars radial velocities (Segransan+, 2000)
J/A+A/398/239 : RI differential photometry of CU Cnc (Ribas, 2003)
J/ApJ/663/573 : Sloan gi light curves of HAT-TR-205-012 (Beatty+, 2007)
J/ApJ/684/635 : New low-mass eclipsing binary from SDSS-II (Blake+, 2008)
J/ApJ/691/1400 : Absolute properties of CM Dra (Morales+, 2009)
J/ApJ/701/764 : Light curves for five M-dwarf stars (Fernandez+, 2009)
J/MNRAS/406/2559 : BVRI light curves of GSC2314-0530 (Dimitrov+, 2010)
J/AJ/141/166 : HATNet variability survey of K and M dwarfs (Hartman+, 2011)
J/ApJ/728/48 : Multicolor eclipse data for 6 new binaries (Kraus+, 2011)
J/ApJ/742/123 : Photometry and Velocity of LSPM J1112+7626 (Irwin+, 2011)
J/MNRAS/426/1507 : Detached M dwarf eclipsing binaries in WTS (Birkby+, 2012)
J/A+A/549/A18 : WASP-30 and J1219-39 light + velocity curves (Triaud+, 2013)
J/MNRAS/431/3240 : Ji photometry of WTS 19g-4-02069 (Nefs+, 2013)
J/A+A/572/A50 : J0113+31 light + velocity curves (Gomez Maqueo Chew+, 2014)
J/ApJ/797/31 : The G+M eclipsing binary V530 Orionis photometry
(Torres+, 2014)
J/MNRAS/437/2831 : 4 transiting F-M binary systems (Zhou+, 2014)
J/MNRAS/451/2263 : Differential photometry of the EB* HATS551-027 (Zhou+, 2015)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Star Star name
16- 17 I2 h RAh Simbad Hour of Right Ascension (J2000)
19- 20 I2 min RAm Simbad Minute of Right Ascension (J2000)
22- 26 F5.2 s RAs Simbad Second of Right Ascension (J2000)
28 A1 --- DE- Simbad Sign of the Declination (J2000)
29- 30 I2 deg DEd Simbad Degree of Declination (J2000)
32- 33 I2 arcmin DEm Simbad Arcminute of Declination (J2000)
35- 38 F4.1 arcsec DEs Simbad Arcsecond of Declination (J2000)
40- 47 F8.6 d Per [2.444949/7.19635] Period from this work
49- 56 F8.6 d e_Per [1e-06/2e-05] Uncertainty in Per
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Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 A14 --- Star Star name
16- 26 A11 "date" Date UT date of observation (mid-exposure)
28- 36 F9.3 d BJD [56588.193/58085.4] Barycentric Julian Date
(BJD-2400000; TDB)
38- 41 I4 s Exp [1200/3000] Exposure time
43- 50 F8.4 km/s RV [-32.479/78.608] Radial velocity
52- 56 F5.3 km/s e_RV [0.011/0.743] Uncertainty in RV
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 21 A21 --- EB Name of eclipsing binary
22- 24 A3 --- m_EB Component designation
26- 28 A3 --- n_EB Note on EB (1)
30- 36 F7.5 Msun Mass [0.091/0.6009] Stellar mass
38- 44 F7.5 Msun e_Mass [0.0003/0.05] Uncertainty in Mass
46- 52 F7.5 Rsun Rad [0.1174/0.641] Stellar radius
54- 60 F7.5 Rsun e_Rad [0.00059/0.06] Uncertainty in Rad
62- 63 I2 --- Ref [1/41] Reference (2)
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Note (1): Note as follows:
a = PRL Advanced Radial velocity Abu-sky Search (PARAS; Chakraborty et al.
2014PASP..126..133C 2014PASP..126..133C) spectra;
b = M dwarf star.
Note (2): Reference as follows:
1 = Triaud et al. (2013, J/A+A/549/A18);
2 = Chaturvedi et al. (2016MNRAS.462..554C 2016MNRAS.462..554C);
3 = Zhou et al. (2014, J/MNRAS/437/2831);
4 = Parsons et al. (2010MNRAS.402.2591P 2010MNRAS.402.2591P);
5 = Parsons et al. (2012MNRAS.426.1950P 2012MNRAS.426.1950P);
6 = Segransan et al. (2003A&A...397L...5S 2003A&A...397L...5S);
7 = Beatty et al. (2007, J/ApJ/663/573);
8 = Ofir et al. (2012MNRAS.423L...1O 2012MNRAS.423L...1O);
9 = Nefs et al. (2013, J/MNRAS/431/3240);
10 = Pyrzas et al. (2012MNRAS.419..817P 2012MNRAS.419..817P);
11 = Zhou et al. (2015, J/MNRAS/451/2263);
12 = Maxted et al. (2007MNRAS.376..919M 2007MNRAS.376..919M);
13 = Gomez Maqueo Chew et al. (2014, J/A+A/572/A50);
14 = Eigmuller et al. (2016AJ....151...84E 2016AJ....151...84E);
15 = Fernandez et al. (2009, J/ApJ/701/764);
16 = Doyle et al. (2011Sci...333.1602D 2011Sci...333.1602D);
17 = Gillen et al. (2017ApJ...849...11G 2017ApJ...849...11G);
18 = Carter et al. (2011Sci...331..562C 2011Sci...331..562C);
19 = Morales et al. (2009, J/ApJ/691/1400);
20 = Blake et al. (2008, J/ApJ/684/635);
21 = Pont et al. (2005A&A...438.1123P 2005A&A...438.1123P);
22 = Hartman et al. (2011, J/AJ/141/166);
23 = Dimitrov & Kjurkchieva (2010, J/MNRAS/406/2559);
24 = Irwin et al. (2011, J/ApJ/742/123);
25 = Irwin et al. (2009ApJ...701.1436I 2009ApJ...701.1436I);
26 = Chaturvedi et al. (2014MNRAS.442.3737C 2014MNRAS.442.3737C);
27 = Vaccaro et al. (2007ApJ...661.1112V 2007ApJ...661.1112V);
28 = Birkby et al. (2012, J/MNRAS/426/1507);
29 = Bouchy et al. (2005A&A...431.1105B 2005A&A...431.1105B);
30 = Kraus et al. (2011, J/ApJ/728/48);
31 = Ribas (2003, J/A+A/398/239);
32 = Lubin et al. (2017ApJ...844..134L 2017ApJ...844..134L);
33 = Lopez-Morales et al. (2006astro.ph.10225L 2006astro.ph.10225L);
34 = Young et al. (2006MNRAS.370.1529Y 2006MNRAS.370.1529Y);
35 = Devor et al. (2008ApJ...687.1253D 2008ApJ...687.1253D);
36 = Huelamo et al. (2009A&A...503..873H 2009A&A...503..873H);
37 = Shkolnik et al. (2010ApJ...716.1522S 2010ApJ...716.1522S);
38 = Torres et al. (2014, J/ApJ/797/31);
39 = Torres & Ribas (2002ApJ...567.1140T 2002ApJ...567.1140T);
40 = Lopez-Morales & Ribas (2005ApJ...631.1120L 2005ApJ...631.1120L);
41 = This work.
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History:
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(End) Tiphaine Pouvreau [CDS] 15-Jan-2019