J/AJ/101/1352 Observations of variable stars in M9 (Clement+, 1991)
A search for double-mode RR Lyrae stars in the globular clusters M 80, M 9,
and NGC 2298.
Clement C.M., Walker I.R.
<Astron. J., 101, 1352-1360 (1991)>
=1991AJ....101.1352C 1991AJ....101.1352C
ADC_Keywords: Clusters, globular ; Stars, variable ; Photometry
Keywords: globular clusters: M80, M9, NGC2298 - stars: variables
Abstract:
Observations of RR Lyrae variables near the transition between
fundamental and first-overtone mode in the Oosterhoff type II (Oo II)
globular clusters M80, M9, and NGC 2298 have been analyzed in a search
for double-mode pulsators (RRd stars). These three clusters were
selected because they have metal abundances that are intermediate
between those of the Oo II clusters and the Oo I clusters that are
known to have RRd stars. Any RRd stars identified in these three
clusters would be useful for verification of a mass-metallicity
relation. The analysis was based on published observations for all
three clusters, and in addition, 44 CCD frames of M9 and 32
photographs of NGC 2298, all obtained with the University of Toronto
telescope at Las Campanas. No new RRd stars were discovered. It is
noted that the only globular clusters known to have RRd stars are the
most metal poor Oo I clusters and metal poor Oo II clusters. Published
observations of the RRd stars in M15 have been analyzed in order to
determine accurate periods and period ratios for stars whose periods
were previously considered to be uncertain.
Description:
Time-series photometry for the variable stars in the globular cluster M9.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 49 7 List of variables
table2.dat 53 44 CCD time-series B photometry for 7 variable
stars in Messier 9 (NGC 6333)
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See also:
J/AJ/89/1707 : M9 variable stars photographic observations (Clement+, 1984)
J/AJ/112/618 : CCD photometry of variable stars in M9 (Clement+, 1996)
J/AJ/118/453 : M9 RR Lyrae CCD observations (Clement+, 1999)
J/MNRAS/434/1220 : Vi light curves of NGC6333 variables (Arellano Ferro+, 2013)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- VName Variable name (VNN),
<Cl* NGC 6333 SAW VNN> in Simbad
6- 7 I2 h RAh Simbad Hour of Right Ascension (J2000.0)
9- 10 I2 min RAm Simbad Minute of Right Ascension (J2000.0)
12- 16 F5.2 s RAs Simbad Second of Right Ascension (J2000.0)
18 A1 --- DE- Simbad Sign of the Declination (J2000.0)
19- 20 I2 deg DEd Simbad Degree of Declination (J2000.0)
22- 23 I2 arcmin DEm Simbad Arcminute of Declination (J2000.0)
25- 28 F4.1 arcsec DEs Simbad Arcsecond of Declination (J2000.0)
30- 34 F5.2 mag Bmag Simbad B band magnitude
36- 39 F4.1 mag Vmag ? Simbad V band magnitude
41- 49 F9.7 d Per ? Period (from the paper)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 11 F11.3 d HJD Heliocentric Julian day
13- 17 F5.2 mag V1mag ?=- B magnitude of V1
19- 23 F5.2 mag V4mag B magnitude of V4
25- 29 F5.2 mag V5mag B magnitude of V5
31- 35 F5.2 mag V6mag B magnitude of V6
37- 41 F5.2 mag V7mag ?=- B magnitude of V7
43- 47 F5.2 mag V8mag ?=- B magnitude of V8
49- 53 F5.2 mag V10mag B magnitude of V10
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Acknowledgements:
Daniel Bramich, ESO, Germany
Armando Arellano Ferro, Instituto de Astronomia, UNAM, Mexico
(End) Daniel Bramich [ESO], Patricia Vannier [CDS] 15-Oct-2013