The Period-Luminosity Relation for the Large Magellanic Cloud Cepheids Derived from Spitzer Archival Data

TL;DR

This study derives the Cepheid period-luminosity relations at multiple infrared wavelengths using Spitzer data for LMC Cepheids, providing valuable calibrations for future extragalactic distance measurements.

Contribution

It presents new infrared P-L and P-C relations for LMC Cepheids, including tests of their linearity, using archival Spitzer data.

Findings

P-L relations at 3.6, 4.5, 5.8, and 8.0 microns derived.

P-C relations found to have relatively flat slopes.

Linearity confirmed at 3.6, 4.5, and 5.8 microns; inconclusive at 8.0 microns.

Abstract

Using Spitzer archival data from the SAGE (Surveying the Agents of a Galaxy's Evolution) program, we derive the Cepheid period-luminosity (P-L) relation at 3.6, 4.5, 5.8 and 8.0 microns for Large Magellanic Cloud (LMC) Cepheids. These P-L relations can be used, for example, in future extragalactic distance scale studies carried out with the James Webb Space Telescope. We also derive Cepheid period-color (P-C) relations in these bands and find that the slopes of the P-C relations are relatively flat. We test the nonlinearity of these P-L relations with the F statistical test, and find that the 3.6 micron, 4.5 micron and 5.8 micron P-L relations are consistent with linearity. However the 8.0 micron P-L relation presents possible but inconclusive evidence of nonlinearity.