J/ApJS/142/71 BVRI observations of LMC Cepheids (Sebo+, 2002)
The Cepheid period-luminosity relation in the Large Magellanic Cloud.
Sebo K.M., Rawson D., Mould J., Madore B.F., Putman M.E., Graham J.A.,
Freedman W.L., Gibson B.K., Germany L.M.
<Astrophys. J. Suppl. Ser. 142, 71 (2002)>
=2002ApJS..142...71S 2002ApJS..142...71S
ADC_Keywords: Magellanic Clouds ; Stars, variable ; Photometry, UBVRI
Keywords: Cepheids - distance scale - Magellanic Clouds -
techniques: photometric
Abstract:
A homogeneous set of ground-based BVRI observations of ∼600 Cepheids
is presented to check the Cepheid period-luminosity (PL) zero point
for the Large Magellanic Cloud (LMC). The sample of Cepheids is
completely self-contained and has been reduced consistently to
eliminate photometric differences caused by combining multiple sources
of photometry.
The Cepheid distances to nearby galaxies obtained by the Hubble Space
Telescope (HST) Key Project on the Extragalactic Distance Scale were
computed assuming a "standard" PL relation based on a compilation of
photoelectric observations of 34 Cepheids and a standard distance
modulus to the LMC of 18.50. The final Key Project results substituted
a statistically stronger PL relation obtained by the OGLE
collaboration. In this paper we compare our data with the OGLE PL
relation; the subsample of LMC Cepheids with similar periods to those
discovered in the nearby galaxies is fainter at the relevant periods
by 0.04±0.02mag than the OGLE sample. Substituting in turn this PL
relation for that of the OGLE collaboration would raise the Hubble
constant by 2%±1%, a correction which is not significant. The
multicolor data set will also be useful in considering the effects of
reddening and chemical composition and deriving an improved Cepheid
period-luminosity relation for the LMC.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 111 1097 LMC Cepheids - Photometry
table4.dat 70 605 LMC Cepheids - Properties
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See also:
J/AcA/49/223 : BVI photometry of OGLE LMC Cepheids (Udalski+, 1999)
J/AcA/49/543 : OGLE LMC + SMC Cepheids VI photometry (Pietrzynski+, 1999)
J/ApJ/507/655 : VI photometry of new Cepheids in NGC 2541 (Ferrarese+ 1998)
J/ApJ/512/48 : VI photometry of new Cepheids in NGC 4725 (Gibson+, 1999)
J/ApJ/514/614 : VI photometry of new Cepheids in NGC 3198 (Kelson+, 1999)
J/ApJ/523/540 : VI photometry of new Cepheids in NGC 3319 (Sakai+, 1999)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Cepheid name
13- 23 F11.5 d VJD-2400000 ? Julian date (+2400000.0) of Vmag
25- 30 F6.3 mag Vmag ? The V band magnitude
32- 36 F5.3 mag e_Vmag ? The error in Vmag
38- 48 F11.5 d BJD-2400000 ? Julian date (+2400000.0) of Bmag
50- 55 F6.3 mag Bmag ? The B band magnitude
57- 61 F5.3 mag e_Bmag ? The error in Bmag
63- 73 F11.5 d RJD-2400000 ? Julian date (+2400000.0) of Rmag
75- 80 F6.3 mag Rmag ? The R band magnitude
82- 86 F5.3 mag e_Rmag ? The error in Rmag
88- 98 F11.5 d IJD-2400000 ? Julian date (+2400000.0) of Imag
100-105 F6.3 mag Imag ? The I band magnitude
107-111 F5.3 mag e_Imag ? The error in Imag
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Cepheid name
13 I1 h RAh Hour of Right Ascension (J2000)
15- 16 I2 min RAm Minute of Right Ascension (J2000)
18- 22 F5.2 s RAs Second of Right Ascension (J2000)
24 A1 --- DE- Sign of the Declination (J2000)
25- 26 I2 deg DEd Degree of Declination (J2000)
28- 29 I2 arcmin DEm Arcminute of Declination (J2000)
31- 34 F4.1 arcsec DEs Arcsecond of Declination (J2000)
36- 39 F4.2 mag delV ? Calculated Vmag error arising from randomly
sampling a Fundamental-mode lightcurve with
a one mag amplitude
41- 46 F6.2 d Period Cepheid period
48- 52 F5.2 mag Bmag The mean phase-weighted B band magnitude
54- 58 F5.2 mag Vmag The mean phase-weighted V band magnitude
60- 64 F5.2 mag Rmag The mean phase-weighted R band magnitude
66- 70 F5.2 mag Imag The mean phase-weighted I band magnitude
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 24-Sep-2002