J/A+A/434/89 Parameters of LMC detached eclipsing binaries (Michalska+, 2005)
Detached binaries in the Large Magellanic Cloud.
A selection of binaries suitable for distance determination.
Michalska G., Pigulski A.
<Astron. Astrophys. 434, 89 (2005)>
=2005A&A...434...89M 2005A&A...434...89M
ADC_Keywords: Magellanic Clouds ; Binaries, eclipsing ; Effective temperatures ;
Stars, diameters
Keywords: stars: binaries: eclipsing - Magellanic Clouds -
stars: fundamental parameters
Abstract:
As a result of a careful selection of eclipsing binaries in the Large
Magellanic Cloud using the OGLE-II photometric database, we present a
list of 98 systems that are suitable targets for spectroscopic
observations that would lead to the accurate determination of the
distance to the LMC. For these systems we derive preliminary
parameters combining the OGLE-II data with the photometry of MACHO and
EROS surveys. In the selected sample, 58 stars have eccentric orbits.
Among these stars we found fourteen systems showing apsidal motion.
The data do not cover the whole apsidal motion cycle, but follow-up
observations will allow detailed studies of these interesting objects.
Description:
Parameters of 98 detached eclipsing binaries in the Large Magellanic
Cloud selected as the best for the purpose of distance determination.
The first 17 columns refer to the results of the fitting by means of
the Wilson-Devinney program, the remaining 16, to the Monte Carlo (M-C)
simulations. The errors given for the M-C simulations correspond to
the 10% increase of the weighted sum of the squares of residuals (SSR)
with respect to the minimum value.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 89 98 List of 98 selected DEBs in the
Large Magellanic Cloud
table3.dat 181 98 Parameters of the selected systems from
Wilson-Devinney fit and Monte Carlo simulations
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See also:
J/AJ/114/326 : MACHO Variables V. (Alcock+ 1997)
J/AcA/53/1 : OGLE eclipsing binaries in LMC (Wyrzykowski+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Sequential number
3 A1 --- n_Seq [*] Note for good target (1)
5- 14 A10 --- LMCSC OGLE LMC SC field
16- 17 I2 h RAh Right ascension (J2000) (2)
18- 19 I2 min RAm Right ascension (J2000) (2)
20- 24 F5.2 s RAs Right ascension (J2000) (2)
25 A1 --- DE- Declination sign (J2000) (2)
26- 27 I2 deg DEd Declination (J2000) (2)
28- 29 I2 arcmin DEm Declination (J2000) (2)
30- 33 F4.1 arcsec DEs Declination (J2000) (2)
35- 46 A12 --- MACHO MACHO designation
48- 51 I4 --- EROS ? EROS number
52- 60 F9.6 d Porb ? Orbital period
62- 67 F6.3 mag Vmag Johnson V magnitude from OGLE-II (3)
69- 74 F6.3 mag V-I Johnson V-I colour index from OGLE-II (3)
76- 95 A20 --- Rem Remarks (4)
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Note (1): * for system that is indicated as good target for distance
determination by Wyrzykowski, 2003, Cat. J/AcA/53/1
Note (2): OGLE name, HHMMSSss+DDMMSSs
Note (3): The photometry is given for the out-of-eclipse phase at maximum light
Note (4): Remarks are:
E = system with non-zero eccentricity
AM = system with detectable apsidal motion
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Sequential number
4- 8 I5 K T1 Effective temperature of star 1 (1)
10- 14 I5 K T2 Effective temperature of star 2 (2)
16- 18 I3 K e_T2 rms error of T2
20- 23 F4.1 deg incl Inclination (2)
25- 27 F3.1 deg e_incl rms error of incl
29- 33 F5.3 --- Sumr Sum of relative radii of star 1 and 2 (2)
35- 39 F5.3 --- e_Sumr rms error of Sumr
41- 44 F4.2 --- Fe1 The parameter Fe for primary eclipse (2)(3)
46- 49 F4.2 --- e_Fe1 rms error of Fe1
51- 54 F4.2 --- Fe2 ? The parameter Fe for secondary eclipse (2)(3)
56- 59 F4.2 --- e_Fe2 ? rms error of Fe2
61- 65 F5.3 --- ecc Eccentricity (2)(4)
67- 71 F5.3 --- e_ecc ? rms error of ecc (5)
73- 77 F5.1 deg omega ? Longitude of periastron (2)(5)
79- 82 F4.1 deg e_omega ? rms error of omega (5)
84- 86 I3 km/s K12 Calculated half-range of radial velocity changes
89- 93 I5 K MC-T2 ? Effective temperature of star 2, from the M-C
simulations (6)(8)
96- 99 I4 K E_MC-T2 ? Positive error of MC-T2 (7)(8)
102-105 I4 K e_MC-T2 ? Negative error of MC-T2 (8)(7)
107-110 F4.1 deg MCincl ? Inclination, from the M-C simulations (8)(6)
112-116 F5.1 deg E_MCincl ? Positive error of MC_i (7)(8)
119-122 F4.1 deg e_MCincl ? Negative error of MC_i (7)(8)
124-128 F5.3 --- MCSumr ? Sum of relative radii of star 1 and 2, from
the M-C simulations (6)(8)
131-135 F5.3 --- E_MCSumr ? Positive error of MC_Sumr (7)(8)
138-142 F5.3 --- e_MCSumr ? Negative error of MC_Sumr (7)(8)
144-147 F4.2 --- MCFe1 ? The parameter Fe for primary eclipse, from the
M-C simulations (3)(6)(8)
150-153 F4.2 --- E_MCFe1 ? Positive error of MC_Fe1 (7)(8)
156-159 F4.2 --- e_MCFe1 ? Negative error of MC_Fe1 (7)(8)
161-164 F4.2 --- MCFe2 ? The parameter Fe for secondary eclipse, from
the M-C simulations (3)(6)(8)
167-170 F4.2 --- E_MCFe2 ? Positive error of MC_Fe2 (7)(8)
173-176 F4.2 --- e_MCFe2 ? Negative error of MC_Fe2 (7)(8)
178-179 A2 --- Obs Code for observations used in the M-C
simulations (8)(9)
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Note (1): Assumed. Sect. 5.1 and Fig. 3 of the paper explains how T1 was
derived.
Note (2): From the fit by means of Wilson-Devinney program.
Note (3): The parameter Fe was defined by Wyithe & Wilson
(2001ApJ...559..260W 2001ApJ...559..260W) and equals to Fe=(r1+r2-cos(incl))/(2*r2), where
r1 and r2 are relative radii of star 1 and 2, respectively. The radii
are measured with respect to the distance between components at the
epoch of mid-time of the eclipse. This means that for a circular
orbit, Fe is the same for both eclipses, while for an eccentric one,
two different values have to be given, for primary and secondary
eclipse. In case of a circular orbit the entries in table for
secondary eclipse remain empty.
Note (4): Assumed to be 0 for circular orbits.
Note (5): Field left empty for circular orbits.
Note (6): This is the value of the parameter in the parameter space
explored by means of the Monte-Carlo simulations for which the
smallest sum of squares of the residuals is yielded.
Note (7): Errors in M-C simulations are not symmetric, so that both
positive and negative deviations are provided. They correspond to such
a change of the parameter that yields a 10% increase of the sum of
squares of residuals with respect to the minimum value.
Note (8): Field left empty for a star with apsidal motion detected.
Note (9): The following bands were used for the M-C simulations:
O = OGLE-II I band
MB = MACHO blue band
MR = MACHO red band
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Acknowledgements: Gabriela Michalska, michalska(at)astro.uni.wroc.pl
(End) Patricia Vannier [CDS] 25-Jan-2005