J/A+A/393/887 SMC Be stars candidates (Mennickent+, 2002)
On Be star candidates and possible blue pre-main sequence objects in the
Small Magellanic Cloud.
Mennickent R.E., Pietrzynski G., Gieren W., Szewczyk O.
<Astron. Astrophys., 393, 887-896 (2002)>
=2002A&A...393..887M 2002A&A...393..887M
ADC_Keywords: Magellanic Clouds ; Stars, pre-main sequence ; Stars, Be ;
Stars, variable ; Photometry
Keywords: stars: pre-main sequence - stars: emission-line, Be -
stars: variable: general - X-rays: binaries -
galaxies: individual: SMC
Abstract:
Recently the OGLE experiment has provided accurate light curves and
colours for about 2 millions stars in the Small Magellanic Cloud. We
have examined this database for its content of Be stars, applying some
selection criteria, and we have found a sample of ∼1000 candidates.
Some of these stars show beautiful light curves with amazing
variations never observed in any Galactic variable. We find outbursts
in 13% of the sample (type-1 stars), high and low states in 15%,
periodic variations in 7%, and the usual variations seen in Galactic
Be stars in 65% of the cases. The Galactic counterparts of type-1
objects could be the outbursting Be stars found by Hubert & Floquet
(1998, Cat. J/A+A/335/565) after the analysis of Hipparcos photometry.
We discuss the possibility that type-1 stars could correspond to Be
stars with accreting white dwarf companions or alternatively, blue
pre-main sequence stars surrounded by thermally unstable accretion
disks. We provide coordinates and basic photometric information for
these stars and some examples of light curves.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 102 Type-1 stars (objects showing outbursts)
table3.dat 61 154 Type-2 stars (objects showing high and low states)
table5.dat 118 78 Type-3 stars (objects showing periodic or
near-periodic long-term oscillations)
table6.dat 61 685 Type-4 stars (objects showing light curves
similar to those observed for Galactic Be stars)
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See also:
J/A+A/335/565 : Be stars variability (Hubert+ 1998)
J/AcA/48/147 : OGLE SMC BVI photometry (Udalski+ 1998)
Byte-by-byte Description of file: table1.dat table3.dat table5.dat table6.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [OGLE]
5- 22 A18 --- OGLE OGLE name (HHMMSS.ss+DDMMSS.s)
25- 29 F5.3 arcsec Dphi Distance to the nearest star detected with
Dophot, Δφ
33- 38 F6.3 mag Vmag V magnitude
41- 46 F6.3 mag B-V B-V colour index
49- 54 F6.3 mag V-I V-I colour index
57- 61 F5.3 mag rms Scatter of I-band magnitude
63 A1 --- l_Time [~] Limit flag on Time
64- 69 F6.2 d Time ? Time scale (for type-3 stars)
71- 75 F5.2 d e_Time ? rms uncertainty on Time
79-118 A40 --- Notes Notes (1)
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Note (1): Abbreviations in Notes as follows:
ART = after removing trend
ChP? = Changing period?
LA = low amplitude
MA = multiple aliases
VA = variable amplitude
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 01-Oct-2013