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Variable stars in nearby galaxies. V. Search for Cepheids in Field A of NGC 6822

E. Antonello·D. Fugazza·L. Mantegazza·M. Stefanon·S. Covino
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Abstract

The results of a CCD survey for variability of stars in the nearby galaxy NGC 6822 are presented. The goal of the survey was to obtain good light curves of Cepheids for Fourier decomposition and to detect shorter period Cepheids. Since the program was carried out with a relatively small telescope, the Dutch 0.9 m at ESO-La Silla, the observations were unfiltered (white light, or Wh-band). The analysis revealed the presence of more than 130 variable stars. 21 population I Cepheids are detected; 6 of them were already known from previous works (Kayser, 1967). For at least three Cepheids, however, the previous identification or period was wrong. Some probable population II (W Vir) stars are also identified. The dispersion of the fundamental mode Cepheid PL relation appears to be small.

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E. Antonello, D. Fugazza, L. Mantegazza, M. Stefanon, S. Covino. 2002-04-02. Variable stars in nearby galaxies. V. Search for Cepheids in Field A of NGC 6822. https://doi.org/10.1051/0004-6361%3A20020320

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