J/AJ/108/932 Variable stars in the SMC cluster NGC 330 (Sebo+, 1994)
Variable stars in and around the SMC cluster NGC 330
Sebo K.M., Wood P.R.
<Astron. J. 108, 932 (1994)>
=1994AJ....108..932S 1994AJ....108..932S (SIMBAD/NED Reference)
ADC_Keywords: Stars, variable ; Photometry, CCD ; Magellanic Clouds
Abstract:
V and I band CCD images of the SMC cluster NGC 330 have been obtained
over an interval of 4 years with the aim of identifying variable stars
in and around this rich, young cluster. The search has revealed 22
Cepheid variables, of which 14 are newly discovered. All of these
appear to belong to the SMC field population rather than being cluster
members. Twenty long-period variables, and nine other variables were
identified including two eclipsing variables (one newly discovered),
and four close binary stars, two of which show emission lines. The
Cepheids indicate that only small to moderate amounts of convective
core overshoot (fov≲0.25) occur during the main-sequence phases for
stars of mass 2-3M☉. The Cepheid period-luminosity-color relation
obtained from VI photometry, when compared to the theoretical relation
of Chiosi, et al. (1993ApJS...86..541C 1993ApJS...86..541C), yields a distance modulus for
the short-period Cepheids observed during this study of 18.92 if no
overshoot is assumed, or 18.72 if moderate overshoot (f_ov=0.25) is
adopted. Only two modes of pulsation are present in this group of
Cepheids, most likely they are the fundamental and first overtone.
Addresses:
Sebo K.M.
Wood P.R.
Mount Stromlo and Siding Spring Observatories, Private Bag,
Weston Creek PO, A.C.T. 2611 Australia
Objects:
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RA (2000) DE Designation(s)
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00 56.2 -72 29 NGC 330
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables 62 2988 Raw data
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Byte-by-byte Description of file: tables
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Bytes Format Units Label Explanations
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1- 4 A4 --- No Star number
6- 16 F11.3 d HJD []? Heliocentric Julian day for Vmag value
18- 23 F6.3 mag Vmag []? V magnitude
25- 29 F5.3 mag e_Vmag []? rms uncertainty on Vmag
33- 43 F11.3 d HJD2 []? Heliocentric Julian day for Imag value
45- 50 F6.3 mag Imag []? I magnitude
52- 56 F5.3 mag e_Imag []? rms uncertainty on I mag
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Origin: AAS CD-ROM series, Volume 3, 1995
(End) Lee Brotzman [ADS] 31-Oct-1994, Patricia Bauer [CDS] 16-Feb-1995