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arXiv · 1007.1499

The Mid-Infrared Period-Luminosity Relations for the Small Magellanic Cloud Cepheids Derived from Spitzer Archival Data

Chow-Choong Ngeow·Shashi M. Kanbur
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Abstract

In this paper we derive the Spitzer IRAC band period-luminosity (P-L) relations for the Small Magellanic Cloud (SMC) Cepheids, by matching the Spitzer archival SAGE-SMC data with the OGLE-III SMC Cepheids. We find that the 3.6micron and 4.5micron band P-L relations can be better described using two P-L relations with a break period at log(P)=0.4: this is consistent with similar results at optical wavelengths for SMC P-L relations. The 5.8micron and 8.0micron band P-L relations do not extend to sufficiently short periods to enable a similar detection of a slope change at log(P)=0.4. The slopes of the SMC P-L relations, for log(P)>0.4, are consistent with their LMC counterparts that were derived from a similar dataset. They are also in agreement with those obtained from a small sample of Galactic Cepheids with parallax measurements.

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Chow-Choong Ngeow, Shashi M. Kanbur. 2010-07-09. The Mid-Infrared Period-Luminosity Relations for the Small Magellanic Cloud Cepheids Derived from Spitzer Archival Data. https://doi.org/10.1088/0004-637x/720/1/626

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