Cepheids and Long Period Variables in NGC 4395

F. Thim; J. G. Hoessel; A. Saha; J. Claver; A. Dolphin; G. A. Tammann

doi:10.1086/382244

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arXiv · astro-ph/0401558

Cepheids and Long Period Variables in NGC 4395

F. Thim·J. G. Hoessel·A. Saha·J. Claver·A. Dolphin·G. A. Tammann

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Abstract

Repeated imaging observations of NGC 4395 were made with the WIYN 3.5 m and the KPNO 2.1 m telescopes. From the photometry of the resolved brighter stars in this galaxy eleven Cepheids with periods ranging between 12 and 90 days have been identified. The true distance modulus has been derived from the apparent distance moduli in g, r and i. The distance modulus is 28.02 +/- 0.18 based on the LMC P-L relation by Sandage et al. 2003; this corresponds to a distance of 4.0 +/- 0.3 Mpc. Using the P-L relation from Madore & Freedman 1991, the distance modulus is 28.15 +/- 0.18; which corresponds to a distance of 4.3 +/- 0.4 Mpc. The reddening is calculated to be E(g-r) = 0.06 +/- 0.08 and E(r-i) = 0.10 +/- 0.08, again from the distance moduli mu_g, mu_r and mu_i. In addition, 37 other variables have been detected, the majority of which have definite periods. They are probably all red long period variables.

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F. Thim, J. G. Hoessel, A. Saha, J. Claver, A. Dolphin, G. A. Tammann. 2004-01-26. Cepheids and Long Period Variables in NGC 4395. https://doi.org/10.1086/382244

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