J/AJ/114/326 MACHO Variables V. (Alcock+ 1997)
The MACHO Project LMC Variable Star Inventory. V. Classification and Orbits of
611 Eclipsing Binary Stars
Alcock C., Allsman R.A., Alves D., Axelrod T.S., Becker A.C.,
Bennett D.P., Cook K.H., Freeman K.C., Griest K., Lacy C.H.S.,
Lehner M.J., Marshall S.L., Minniti D., Peterson B.A., Pratt M.R.,
Quinn P.J., Rodgers A.W., Stubbs C.W., Sutherland W., , Welch D.L.
<Astron. J. 114, 326 (1997)>
=1997AJ....114..326A 1997AJ....114..326A
ADC_Keywords: Binaries, eclipsing ; Binaries, orbits ; Photometry ;
Magellanic Clouds
Abstract:
We report the characteristics of 611 eclipsing binary stars in the
Large Magellanic Cloud found by using the MACHO Project photometry
database. The sample is magnitude limited, and extends down the main
sequence to about spectral type A0. Many evolved binaries are also
included. Each eclipsing binary is classified according to the
traditional scheme of the General Catalogue of Variable Stars (EA and
EB), and also according to a new decimal classification scheme defined
in this paper. The new scheme is sensitive to the two major sources of
variance in eclipsing binary star light curves -- the sum of radii,
and the surface-brightness ratio, and allow greater precision in
characterizing the light curves. Examples of each type of light curve
and their variations are given. Sixty-four of the eclipsing binaries
have eccentric, rather than circular, orbits. The ephemeris and
principal photometric characteristics of each eclipsing binary are
listed in a table. Photometric orbits based on the Nelson-Davis-Etzel
model have been fitted to all light curves. These data will be useful
for planning future observations of these binaries. Plots of all data
and fitted orbits and a table of the fitted orbital parameters are
available on the AAS CD-ROM series, Vol. 9, 1997. These data are also
available at the MACHO home page (http://wwwmacho.mcmaster.ca/).
(c) 1997 American Astronomical Society.
Description:
As submitted by the author, 637 PostScript figures containing light
curves for the LMC eclipsing binary stars in the V and R bands are
contained in a single UNIX tape archive (tar) file. The individual
files have names of the form 'machohh:mm:ss.s-dd:mm:ss.ps', which do
not conform to the CD-ROM ISO 9660 Standard Interchange Level 1,
therefore they have been left in the original tar format.
The PostScript figures are available on the CD-ROM.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 139 637 Properties of eclipsing binaries in the LMC
table4.dat 112 1274 Photometric Orbital Parameters
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See also:
http://wwwmacho.mcmaster.ca/ MACHO home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh Right ascension (J2000.0)
3 A1 --- --- Always ':'
4- 5 I2 min RAm Right ascension (J2000.0)
6 A1 --- --- Always ':'
7- 10 F4.1 s RAs Right ascension (J2000.0)
13 A1 --- DE- Declination sign
14- 15 I2 deg DEd Declination (J2000.0)
16 A1 --- --- Always ':'
17- 18 I2 arcmin DEm Declination (J2000.0)
19 A1 --- --- Always ':'
20- 21 I2 arcsec DEs Declination (J2000.0)
22 A1 --- Comp [abc] Indicator of multiple observations
24- 28 A5 --- Type *Classification types
31- 35 F5.2 mag VMax V magnitude at maximum brightness
37- 41 F5.2 mag VMinI V magnitude at first minimum
43- 47 F5.2 mag VMinII V magnitude at second minimum
50- 54 F5.2 mag V-R V-R color
56- 67 F12.4 JD Epoch Epoch of the primary minimum
69- 74 F6.4 JD e_Epoch Standard error of the Epoch
76- 85 F10.6 d Per Orbital period
88- 92 F5.3 --- DI [0/1] Primary eclipse duration
(phase units)
95- 97 I3 --- o_Vfilt Number of observations in V filter
100-104 F5.3 mag SDv Std deviation of residuals from fits (V)
107-109 I3 --- o_Rfilt Number of observations in R filter
112-116 F5.3 mag SDr Std deviation of residuals from fits (R)
119-140 A22 --- Notes *Notes
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Note on Type:
The type is in the form: XX/NN, where XX is either EA or EB from the
General Catalog of Variable Stars and NN is an integer from 1 to 10,
inclusive. The numeric classifications are based on the two major
sources of variance in the shapes of the eclipsing binary light
curves, (1) the sum of the relative radii (r1 + r2), and (2) the
surface brightness ratio Js/Jp. Classes 1, 2, and 3 have a surface
brightness ratio near unity; classes 4, 5, and 6 have a surface
brightness ratio near 0.5; classes 7, 8, and 9 have a surface
brightness ratio near 0.18. Classes 1, 4, and 7 have a sum of radii
near 0.4; classes 2, 5, and 8 have a sum of radii near 0.7; classes 3,
6, and 9 have a sum of radii near unity. Class 10 is reserved for
"Algol-like" systems in which the effects of a secondary component
larger than the primary and a large mass ratio are evident in the
light curve from the broad and deep "wings" on the eclipses.
Note on Notes:
An asterisk, "*", indicates that there are multiple sets of
observations of this star. The line of data above or below the
asterisk refers to independent observations of the same star.
Other notes are entered in full.
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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- 2 I2 h RAh Right ascension (J2000.0)
3 A1 --- --- Always ':'
4- 5 I2 min RAm Right ascension (J2000.0)
6 A1 --- --- Always ':'
7- 10 F4.1 s RAs Right ascension (J2000.0)
12 A1 --- DE- Declination sign
13- 14 I2 deg DEd Declination (J2000.0)
15 A1 --- --- Always ':'
16- 17 I2 arcmin DEm Declination (J2000.0)
18 A1 --- --- Always ':'
19- 20 I2 arcsec DEs Declination (J2000.0)
21 A1 --- Comp [abc] Indicator of multiple observations
23 A1 --- Color [VR] Color band for the following data
25- 29 F5.3 --- Js Surface brightness of the secondary (Jp=1)
31- 35 F5.3 --- e_Js Error in Js
37- 41 F5.3 solRad rp Radius of the primary
43- 47 F5.3 solRad e_rp Error in rp
49- 52 F4.2 --- k Ratio of the radii
54- 57 F4.2 --- x Limb-darkening coefficient
59- 62 F4.1 deg i Orbital inclination
64- 67 F4.1 deg e_i Error in i
69- 75 F7.4 --- ecosw ?=0.0000 e*cosω component of eccentricity
77- 82 F6.4 --- e_ecosw ?=0.0000 Error in ecosw
84- 90 F7.4 --- esinw ?=0.0000 e*sinω component of eccentricity
92- 97 F6.4 --- e_esinw ?=0.0000 Error in esinw
99-102 F4.2 --- q Assumed mass ratio
104-106 I3 --- N Number of observations
108-112 F5.3 --- SD Standard deviation of the residuals of the fit
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Origin: AAS CD-ROM series, Volume 9, 1997 Lee Brotzman [ADS] 05-Nov-1997
References:
Alcock et al., Paper I. 1995AJ....109.1653A 1995AJ....109.1653A
Alcock et al., Paper II. 1996AJ....111.1146A 1996AJ....111.1146A
Alcock et al., Paper III. 1997ApJ...482...89A 1997ApJ...482...89A
Alcock et al., Paper IV. 1996ApJ...470..583A 1996ApJ...470..583A
(End) [CDS] 05-Feb-1998