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arXiv · 1006.1553

Cepheid Period-Luminosity Relation from the AKARI Observations

Chow-Choong Ngeow·Yoshifusa Ita·Shashi M. Kanbur·Hilding Neilson·Takashi Onaka·Daisuke Kato
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Abstract

In this paper, we derive the period-luminosity (P-L) relation for Large Magellanic Cloud (LMC) Cepheids based on mid-infrared AKARI observations. AKARI's IRC sources were matched to the OGLE-III LMC Cepheid catalog. Together with the available I band light curves from the OGLE-III catalog, potential false matches were removed from the sample. This procedure excluded most of the sources in the S7 and S11 bands: hence only the P-L relation in the N3 band was derived in this paper. Random-phase corrections were included in deriving the P-L relation for the single epoch AKARI data, even though the derived P-L relation is consistent with the P-L relation without random-phase correction, though there is a \sim 7 per-cent improvement in the dispersion of the P-L relation. The final adopted N3 band P-L relation is N3 = -3.246 log(P) + 15.844, with a dispersion of 0.149.

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Chow-Choong Ngeow, Yoshifusa Ita, Shashi M. Kanbur, Hilding Neilson, Takashi Onaka, Daisuke Kato. 2010-06-08. Cepheid Period-Luminosity Relation from the AKARI Observations. https://doi.org/10.1111/j.1365-2966.2010.17164.x

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