J/AJ/140/14 Variability of luminous stars in LMC (Szczygiel+, 2010)
Variability of luminous stars in the Large Magellanic Cloud using 10 years of
ASAS data.
Szczygiel D.M., Stanek K.Z., Bonanos A.Z., Pojmanski G., Pilecki B.,
Prieto J.L.
<Astron. J., 140, 14-24 (2010)>
=2010AJ....140...14S 2010AJ....140...14S
ADC_Keywords: Magellanic Clouds ; Stars, variable ; Stars, luminous
Keywords: binaries: eclipsing - Magellanic Clouds - stars: massive -
stars: variables: general
Abstract:
Motivated by the detection of a recent outburst of the massive
luminous blue variable LMC-R71, which reached an absolute magnitude
MV=-9.3mag, we undertook a systematic study of the optical
variability of 1268 massive stars in the Large Magellanic Cloud, using
a recent catalog by Bonanos et al. (2009, Cat. J/AJ/138/1003) as the
input. The ASAS All Star Catalog provided well-sampled light curves of
these bright stars spanning 10 years. Combining the two catalogs
resulted in 599 matches, on which we performed a variability search.
We identified 117 variable stars, 38 of which were not known before,
despite their brightness and large amplitude of variation. We found 13
periodic stars that we classify as eclipsing binary (EB) stars, 8 of
which are newly discovered bright massive EBs composed of OB-type
stars. The remaining 104 variables are either semi- or non-periodic,
the majority (85) being red supergiants (RSGs). Most (26) of the newly
discovered variables in this category are also RSGs with only three B
and four O stars.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 130 117 Parameters of 117 variable stars identified in
this Study
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See also:
II/264 : ASAS Variable Stars in Southern hemisphere (Pojmanski+ 2002-05)
J/AJ/138/1003 : IR photometry of massive LMC stars (Bonanos+, 2009)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Star designation (1)
17- 26 F10.7 deg RAdeg Right Ascension in decimal degrees (J2000)
28- 38 F11.7 deg DEdeg Declination in decimal degrees (J2000)
40- 44 F5.2 mag Vmag Mean ASAS V band magnitude
46- 49 F4.2 mag Vamp Amplitude in V band
51- 55 F5.2 mag Imag ? Mean ASAS I band magnitude
57- 60 F4.2 mag Iamp ? Amplitude in I band
62- 80 A19 --- SpType MK spectral type
82- 86 F5.3 mag E(V-I) ? Mean E(V-I) extinction (2)
88- 92 A5 --- GCVS GCVS LMC designation
94-130 A37 --- Notes Neighbor notes (3)
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Note (1): Following Bonanos (2009, Cat. J/AJ/138/1003):
* Breysacher et al. (BAT99; 1999A&AS..137..117B 1999A&AS..137..117B),
* Sanduleak (Sk; 1970CoTol..89....1S 1970CoTol..89....1S),
* Brunet et al. (BI; 1975A&AS...21..109B 1975A&AS...21..109B),
* Lucke (LH; 1972, PhD thesis, Univ. of Washington, CTIO85 in Simbad),
* Henize (S; 1956ApJS....2..315H 1956ApJS....2..315H, LHA 120-S in Simbad),
* Parker et al. (P92; 2001, Cat. J/AJ/121/891, PGMW in Simbad),
* Massey (M02; 2002, Cat. II/236, [M2002] LMC in Simbad).
[SP77]39-33 is a misprint for [SP77]29-33 (corrected in the table by CDS).
Note (2): Taken from Pejcha & Stanek (2009ApJ...704.1730P 2009ApJ...704.1730P).
0.000 correspond to negative values for the calculated extinction, which is
the case for 30 out of 101 stars for which the extinction value was available.
Note (3): Approximate brightness and distance of close neighbors, based on DSS
images. See Section 3.3 for details.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 08-Jun-2012