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The Discovery of Cepheids and a New Distance to NGC 2841 Using the Hubble Space Telescope

L. M. Macri·P. B. Stetson·G. D. Bothun·W. L. Freedman·P. M. Garnavich·S. Jha·B. F. Madore·M. W. Richmond
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Abstract

We report on the discovery of Cepheids in the spiral galaxy NGC 2841, based on observations made with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope. NGC 2841 was observed over 12 epochs using the F555W filter, and over 5 epochs using the F814W filter. Photometry was performed using the DAOPHOT/ALLFRAME package. We discovered a total of 29 variables, including 18 high-quality Cepheids with periods ranging from 15 to 40 days. Period-luminosity relations in the V and I bands, based on the high-quality Cepheids, yield an extinction-corrected distance modulus of 30.74 +/- 0.23 mag, which corresponds to a distance of 14.1 +/- 1.5 Mpc. Our distance is based on an assumed LMC distance modulus of 18.50 +/- 0.10 mag (D = 50+/- 2.5 kpc) and a metallicity dependence of the Cepheid P-L relation of gamma (VI) = -0.2 +/- 0.2 mag/dex.

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L. M. Macri, P. B. Stetson, G. D. Bothun, W. L. Freedman, P. M. Garnavich, S. Jha, B. F. Madore, M. W. Richmond. 2001-05-28. The Discovery of Cepheids and a New Distance to NGC 2841 Using the Hubble Space Telescope. https://doi.org/10.1086/322395

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