J/AJ/123/3216 BV photometry of variable stars in SMC (Sharpee+, 2002)
BV photometry of variable stars in the northeast arm of the
Small Magellanic Cloud.
Sharpee B., Stark M., Pritzl B., Smith H., Silbermann N., Wilhelm R.,
Walker A.
<Astron. J. 123, 3216 (2002)>
=2002AJ....123.3216S 2002AJ....123.3216S
ADC_Keywords: Magellanic Clouds ; Stars, variable ; Photometry, UBV
Keywords: Cepheids - Magellanic Clouds
Abstract:
B and V photometry has been obtained for variable stars in the
northeast arm of the Small Magellanic Cloud (SMC). Periods and light
curves have been determined for 237 periodic variables, including 201
Cepheids, 68 of which are newly discovered. Fundamental-mode Cepheids
and first-overtone mode Cepheids are generally well separated in the BV
color-magnitude diagram, with the latter having bluer mean colors than
the former. The Cepheid period-color relationship for this outlying
SMC field is indistinguishable from that seen in more centrally
located SMC fields and is bluer than theoretical predictions. The red
edge to the populated portion of the instability strip shifts to bluer
colors for fainter Cepheids. There is support from our sample for a
previously reported steepening in the slope of the period-luminosity
relation for fundamental-mode Cepheids near a period of 2 days. The
Cepheids of the northeast arm may be closer to us than are those of
the main body of the SMC, but the difference is smaller than or equal
to about 4kpc, comparable to the tidal radius of the SMC.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 23 84 Coordinates of New Variables
table3.dat 54 58 Photometry of local standard stars
table5.dat 49 10550 Photometry of Individual Variable Stars
table6.dat 90 237 Attributes of Observed Variables
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See also:
V/97 : Updated 3rd Cat Variable Stars in Globular Clusters (Clement+ 1997)
J/AcA/49/437 : BVI photometry of OGLE SMC Cepheids (Udalski+, 1999)
J/AcA/49/543 : OGLE LMC + SMC Cepheids VI photometry (Pietrzynski+, 1999)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- [SSP2002] The new variable SSP number
4 I1 h RAh Hour of Right Ascension (J2000)
6- 7 I2 min RAm Minute of Right Ascension (J2000)
9- 12 F4.1 s RAs Second of Right Ascension (J2000)
14 A1 --- DE- Sign of the Declination (J2000)
15- 16 I2 deg DEd Degree of Declination (J2000)
18- 19 I2 arcmin DEm Arcminute of Declination (J2000)
21- 22 I2 arcsec DEs Arcsecond of Declination (J2000)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1 A1 --- [SSP2002] [A-U] Identification letter
3- 4 I2 h RAh Right ascension (J2000.0)
6- 7 I2 min RAm Right ascension (J2000.0)
9- 12 F4.1 s RAs Right ascension (J2000.0)
15 A1 --- DE- Declination sign (J2000.0)
16- 17 I2 deg DEd Declination (J2000.0)
19- 20 I2 arcmin DEm Declination (J2000.0)
22- 23 I2 arcsec DEs Declination (J2000.0)
25- 30 F6.3 mag Vmag V magnitude
33- 38 F6.3 mag B-V B-V colour index
41- 46 F6.3 mag U-B ? U-B colour index
49- 54 F6.3 mag V-Ic V-Ic colour index
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Star Variable identifier (G1)
14 I1 --- Field [1-4] Field from which measurement was taken
17 A1 --- Band [BV] Band of Observation
20- 31 F12.4 d HJD The Heliocentric Julian date of the observation
36- 41 F6.3 mag mag The Band magnitude
45- 49 F5.3 mag e_mag The 1σ error in mag
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Star Variable identifier (G1)
17- 21 A5 --- Type Variable type (2)
23- 30 F8.5 d Per Period (3)
32- 37 F6.3 mag Bmag ? The luminosity-weighted mean B band magnitude
39- 44 F6.3 mag Vmag ? The luminosity-weighted mean V band magnitude
46- 51 F6.3 mag (B-V)L ? The luminosity-weighted mean (B-V) color
53- 58 F6.3 mag (B-V)M ? The magnitude-weighted mean (B-V) color
60- 63 A4 --- Qual Quality code (4)
65 A1 --- Notes Additional notes (5)
67- 68 I2 h RAh Right ascension (J2000.0) (6)
70- 71 I2 min RAm Right ascension (J2000.0) (6)
73- 77 F5.2 s RAs Right ascension (J2000.0) (6)
80 A1 --- DE- Declination sign (J2000.0) (6)
81- 82 I2 deg DEd Declination (J2000.0) (6)
84- 85 I2 arcmin DEm Declination (J2000.0) (6)
87- 90 F4.1 arcsec DEs Declination (J2000.0) (6)
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Note (2): Variable type:
F = Cepheid pulsating in the fundamental mode;
O = Cepheid pulsating in the first overtone mode;
RRab = RR Lyrae star in the fundamental mode;
RRc = RR Lyrae star in the first overtone mode;
E = Eclipsing variable star.
Note (3): Typically good to a few parts in 105.
Note (4): Quality code:
1 = variable with a relatively complete and well defined light-curve;
2 = light-curve is noisy or has substantial gaps;
1(V) = good light-curve was obtained in V but not in B;
1(B) = good light-curve was obtained in B but not in V.
Note (5): Additional notes:
a = Payne-Gaposchkin & Gaposchkin (1966, Variable Stars in the Small
Magellanic Cloud (Washington: GPO)) give P (days) = 0.527340
and classify as possible RRab.
b = Probable blue companion (Arp, 1960AJ.....65..404A 1960AJ.....65..404A).
c = Payne-Gaposchkin & Gaposchkin (1966, Variable Stars in the Small
Magellanic Cloud (Washington: GPO)) classify as possible
irregular, typing here indeterminate.
d = Much brighter here ( = 18.528) than in Smith et al.
(1992AJ....104.1430S 1992AJ....104.1430S) ( = 20.1).
e = Non-periodic?
f = Possible blue companion?
g = Noisy light curve makes typing uncertain
h = Noise in curves mimicking periodicity?
i = Blue companion?, also alternate period P=0.47541 days.
j = Blue companion?
k = Blue companion?
l = Extremely low amplitude in V, curve morphology in B more
indicative of fundamental mode
Note (6): Positions taken from table2 for SSP stars, and from
Simbad or GCVS (II/214).
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Global notes:
Note (G1): Star identification:
HV NNNN = Harvard Variable;
NGC362V N = Clement et al. (2001AJ....122.2587C 2001AJ....122.2587C);
Cl* NGC 362 SAW V N in Simbad
[SSB92] NNN = Smith et al. (1992AJ....104.1430S 1992AJ....104.1430S);
SSP NN = Table 2 new variable designation, [SSP2002] NN in Simbad
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History:
From electronic version of the journal -- positions added in table6.
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 23-Jul-2002