J/PASP/114/656 Stellar variability in field stars (Everett+, 2002)
Stellar variability in a survey of field stars.
Everett M.E., Howell S.B., van Belle G.T., Ciardi D.R.
<Publ. Astron. Soc. Pac. 114, 656 (2002)>
=2002PASP..114..656E 2002PASP..114..656E
ADC_Keywords: Stars, variable ; Photometry, UBVRI
Abstract:
We present results from a 5 night wide-field time-series photometric
survey that detects variable field stars. We find that the fraction of
stars whose light curves show variations depends on color and
magnitude, reaching 17% for the brightest stars in this survey (V∼4)
for which the photometric precision is best. The fraction of stars
found to be variable is relatively high at colors bluer than the Sun
and relatively low at colors similar to the Sun and increases again
for stars redder than the Sun. We present light curves for a sample of
the pulsating and eclipsing variables. Most of the stars identified as
pulsating variables have low amplitudes (ΔV=0.01-0.05),
relatively blue colors, and multiple periods. There are 13 stars we
identify as either SX Phoenicis or δ Scuti stars. These classes
represent a significant contribution to the total number of blue
variables found in this survey. Another 17 stars are identified as
eclipsing variables, which have a wide range in color, magnitude, and
amplitude. Two variable giants are observed, and both show
night-to-night ∼1% variations. We present data for 222 variables in
total, most of which are not classified. Implications of surveys for
stellar variability and interferometry are briefly discussed.
On 2000 March 16-20 UT we observed a time series of images in V and one
or two images each in UBRI toward two 59'x59' fields using the NOAO
Mosaic Camera at the Kitt Peak 0.9 m telescope.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 92 222 Variable stars
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Table 1: Survey fields
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Field RA (2000) DE GLON GLAT Number of observations
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1 06 06 00 +45 40 00 167 +12 200
2 14 09 30 +53 20 00 99 +60 250
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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- 8 A8 --- [EHV2002] Identification number (F-N-NNNN)
10- 11 I2 h RAh Right ascension (J2000.0)
13- 14 I2 min RAm Right ascension (J2000.0)
16- 19 F4.1 s RAs Right ascension (J2000.0)
21 A1 --- DE- Declination sign (J2000.0)
22- 23 I2 deg DEd Declination (J2000.0)
25- 26 I2 arcmin DEm Declination (J2000.0)
28- 29 I2 arcsec DEs Declination (J2000.0)
31- 34 F4.1 mag Vmag V magnitude (1)
36- 39 F4.1 mag U-B ? U-B colour index (1)
41- 44 F4.1 mag B-V ? B-V colour index (1)
46- 48 F3.1 mag V-R ? V-R colour index (1)
50- 52 F3.1 mag B-I ? B-I colour index (1)
54- 56 F3.1 mag V-I ? V-I colour index (1)
58- 75 A18 --- Class Classification based on light curve (2)
77 A1 --- Note [*] *: star with light curve presented in
this paper (see electronic version)
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Note (1): Filters:
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Filter Central waves FHWM
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U 3577Å 646Å
B 4360Å 990Å
V 5370Å 940Å
R 6440Å 1510Å
I 8220Å 1930Å
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Note (2): Classification:
EA: EA eclipsing binary
EW: EW eclipsing binary
RRab: RRab variable
SX Phe/delta Scuti: SX Phoenicis or delta Scuti stars
U: unclassified variables
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History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 24-Sep-2002