J/AJ/132/2556 ARAUCARIA project: Cepheids in NGC 55 (Pietrzynski+, 2006)
The Araucaria project: the distance to the Sculptor group galaxy NGC 55 from a
newly discovered abundant cepheid population.
Pietrzynski G., Gieren W., Soszynski I., Udalski A., Bresolin F.,
Kudritzki R.-P., Mennickent R., Walker A., Garcia A., Szewczyk O.,
Szymanski M., Kubiak M., Wyrzykowski L.
<Astron. J., 132, 2556-2565 (2006)>
=2006AJ....132.2556P 2006AJ....132.2556P
ADC_Keywords: Stars, variable ; Photometry, UBVRI ; Galaxies, nearby
Keywords: Cepheids; distance scale; galaxies: distances and redshifts;
galaxies: individual (NGC 55); galaxies: stellar content
Abstract:
We have detected, for the first time, Cepheid variables in the
Sculptor Group SB(s)m galaxy NGC 55. From wide-field images obtained
in the optical V and I bands during 77 nights in 2002-2003, we have
found 143 Cepheids with periods ranging from 5.6 to 175.9 days; 133 of
these objects have periods longer than 10 days, making NGC 55 to date
the galaxy with the largest known number of long-period Cepheids in
the Sculptor Group.
Description:
All the data presented in this paper were collected with the Warsaw
1.3m telescope at Las Campanas Observatory. The telescope was
equipped with a mosaic 8kx8k detector, with a field of view of about
35'x35' and a scale of about 0.25"/pix. V- and I-band images of NGC 55
were secured during 77 different nights. 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 in
order to accurately calibrate the data and improve the periods of the
detected variable stars.
Objects:
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RA (2000) DE Designation(s)
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00 15 08.4 -39 13 13 NGC 55 = APMBGC 293-132-031
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 35 10361 Individual V and I observations
table3.dat 73 143 Cepheids in NGC 55
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See also:
J/A+A/450/873 : ARAUCARIA: NGC 6822 variables (Mennickent+, 2006)
J/AJ/123/789 : ARAUCARIA: NGC 300 Cepheid variables (Pietrzynski+, 2002)
J/AJ/128/1167 : ARAUCARIA: NGC 300 Cepheid variables (Gieren+, 2004)
J/AJ/128/2815 : ARAUCARIA: NGC 6822 Cepheid variables (Pietrzynski+, 2004)
J/MNRAS/350/679 : BV photometry of NGC 300 variables (Mennickent+, 2004)
J/ApJ/672/266 : ARAUCARIA: NGC 55 Cepheids JK magnitudes (Gieren+, 2008)
J/A+A/485/41 : NGC 55 blue massive stars VLT-spectroscopy (Castro+, 2008)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [cep]
4- 6 I03 --- cep Cepheid identification ([PGS2006] cepNNN)
8 A1 --- Filt [VI] Filter used in the observation
10- 22 F13.5 d JD Julian date of the observation
24- 29 F6.3 mag mag Observed magnitude in Filt
31- 35 F5.3 mag e_mag The 1σ uncertainty in mag
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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- 3 A3 --- --- [cep]
4- 6 I03 --- cep Cepheid identification ([PGS2006] cepNNN)
8 I1 h RAh Hour of Right Ascension (J2000)
10- 11 I2 min RAm Minute of Right Ascension (J2000)
13- 17 F5.2 s RAs Second of Right Ascension (J2000)
19 A1 --- DE- Sign of the Declination (J2000)
20- 21 I2 deg DEd Degree of Declination (J2000)
23- 24 I2 arcmin DEm Arcminute of Declination (J2000)
26- 29 F4.1 arcsec DEs Arcsecond of Declination (J2000)
31- 38 F8.4 d Per Period
40- 52 F13.5 d T0 Julian date of maximum brightness in the V band
54- 59 F6.3 mag <Vmag> ?=99.999 Mean V band intensity magnitude
61- 66 F6.3 mag <Imag> ?=99.999 Mean I band intensity magnitude
68- 73 F6.3 mag <Wmag> ?=99.999 Mean Wesenheit WI intensity mag.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 07-Mar-2008