The Cepheid Period-Luminosity Relation (The Leavitt Law) at Mid-Infrared Wavelengths: IV. Cepheids in IC 1613

Abstract

We present mid-infrared Period-Luminosity relations for Cepheids in the Local Group galaxy IC1613. Using archival IRAC imaging data from Spitzer we were able to measure single-epoch magnitudes for five, 7 to 50-day, Cepheids at 3.6 and 4.5 microns. When fit to the calibrating relations, measured for the Large Magellanic Cloud Cepheids, the data give apparent distance moduli of 24.29 +/- 0.07 and 24.28 +/- 0.07 at 3.6 and 4.5 microns, respectively. A multi-wavelength fit to previously published BVRIJHK apparent moduli and the two IRAC moduli gives a true distance modulus of 24.27 +/- 0.02 mag with E(B-V) = 0.08 mag, and a corresponding metric distance of 715 kpc. Given that these results are based on single-phase observations derived from exposures having total integration times of only 1,000 sec/pixel we suggest that Cepheids out to about 2 Mpc are accessible to Spitzer with modest integration times during its warm mission. We identify the main limiting factor to this method to be crowding/contamination induced by the ubiquitous population of infrared-bright AGB stars.

arXiv commentAccepted to ApJ December 2008: 9 pages, 3 figures

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Cited by in corpus (15)

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• Galactic Cepheids with Spitzer: I. Leavitt Law and Colors
• The ACS LCID Project. II. Faint Variable Stars in the Isolated Dwarf Irregular Galaxy IC1613
• The Carnegie Hubble Program
• The Araucaria Project. A Distance Determination to the Local Group Spiral M33 from Near-Infrared Photometry of Cepheid Variables
• New period-luminosity and period-color relations of classical Cepheids. IV. The low-metallicity galaxies IC 1613, WLM, Pegasus, Sextans A and B, and Leo A in comparison to SMC
• High-precision distance measurements with classical pulsating stars
• The Carnegie Hubble Program: The Infrared Leavitt Law in IC 1613
• The Araucaria Project. Infrared Tip of the Red Giant Branch Distances to Five Dwarf Galaxies in the Local Group
• Carbon stars as standard candles: II. The median J magnitude as a distance indicator
• Period-Luminosity Relations for Cepheid Variables: From Mid-Infrared to Multi-Phase
• Carbon stars as standard candles -- III. Un-binned maximum likelihood fitting and comparison with TRGB estimations
• On the Form of the Spitzer Leavitt Law and its Dependence on Metallicity
• Evidence for Photometric Contamination in Key Observations of Cepheids in the Benchmark Galaxy IC 1613