J/AJ/128/2815 ARAUCARIA project: NGC 6822 Cepheid variables (Pietrzynski+, 2004)
The Araucaria project: the distance to the Local Group galaxy NGC 6822 from
cepheid variables discovered in a wide-field imaging survey.
Pietrzynski G., Gieren W., Udalski A., Bresolin F., Kudritzki R.-P.,
Soszynski I., Szymanski M., Kubiak M.
<Astron. J., 128, 2815-2825 (2004)>
=2004AJ....128.2815P 2004AJ....128.2815P
ADC_Keywords: Stars, variable ; Photometry, UBVRI
Keywords: Cepheids - distance scale - galaxies: distances and redshifts -
galaxies: individual (NGC 6822) - galaxies: stellar content
Abstract:
We have obtained mosaic images of NGC 6822 in the V and I bands on 77
nights. From these data, we have conducted an extensive search for
Cepheid variables over the entire field of the galaxy, and we have
found 116 such variables with periods ranging from 1.7 to 124 days. We
used the long-period (>5.6 days) Cepheids to establish the
period-luminosity (PL) relations in V, I, and in the
reddening-independent Wesenheit index, which are all very tightly
defined.
Description:
All the data presented in this paper were collected with the Warsaw
1.3m telescope at Las Campanas Observatory. Most of the observations
were obtained in 2002 between July 3 and November 21. Additional
observations were made during three photometric nights in 2003 May.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 88 116 Cepheids in NGC 6822
table2.dat 35 13199 Individual V and I observations
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See also:
J/AJ/123/789 : Araucaria : NGC 300 Cepheid variables (Pietrzynski+, 2002)
J/MNRAS/350/679 : BV photometry of NGC 300 variables (Mennickent+, 2004)
J/AJ/128/1167 : Araucaria : NGC 300 Cepheid Variables. II (Gieren+, 2004)
J/A+A/431/1189 : BV photometry of NGC 6822 variables (Baldacci+, 2005)
J/ApJ/647/1056 : Araucaria: NGC 6822 Cepheid variables (Gieren+, 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- [PGU2004] Cepheid identification
8- 9 I2 h RAh Hour of right ascension (J2000)
11- 12 I2 min RAm Minute of right ascension (J2000)
14- 18 F5.2 s RAs Second of right ascension (J2000)
20 A1 --- DE- Sign of the Declination (J2000)
21- 22 I2 deg DEd Degree of declination (J2000)
24- 25 I2 arcmin DEm Arcminute of declination (J2000)
27- 30 F4.1 arcsec DEs Arcsecond of declination (J2000)
32- 39 F8.4 d Per Period
41- 52 F12.4 d T0 Heliocentric Julian Date of maximum V-band
light
54- 59 F6.3 mag <Vmag> Mean V-band magnitude
61- 66 F6.3 mag <Imag> ?=99.999 Mean I-band magnitude
68- 73 F6.3 mag WI ?=99.999 Wesenheit index (1)
75- 88 A14 --- CrossID Cross-identifications
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Note (1): Defined as WI=Imag-1.55(<Vmag>-<Imag>).
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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- 6 A6 --- [PGU2004] Cepheid identification
8 A1 --- Filt [VI] Filter
10- 22 F13.5 d HJD Heliocentric Julian Date
24- 29 F6.3 mag mag Observed magnitude
31- 35 F5.3 mag e_mag Error in mag
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 15-Jun-2005