Surface Photometry of Star Clusters in the Dwarf Elliptical
نویسندگان
چکیده
We present the surface photometry of star clusters in the nearby dwarf elliptical galaxies NGC 185 and NGC 205, obtained from deep HSTWFPC2 F555W (V ) and F814W (I) images. We have obtained surface brightness and color profiles of six star clusters in NGC 185, seven star clusters in NGC 205, and one recently discovered non-stellar object in NGC 205. The surface brightness profiles of ten star clusters are fitted well by the King model, and those of four star clusters are fitted well by the power-law. Three out of ten star clusters fitted well with King model show signs of tidal tails. It is essential to understand the structures of star clusters in studying the dynamical evolutions of star clusters. There have been several studies on the structures of star clusters in nearby galaxies (LMC, SMC, Fornax dwarf spheroidal, WLM, M31, and NGC 5128). However, there is to date no study of the structures of star clusters in dwarf elliptical galaxies. We present, for the first time, the surface photometry results of star clusters in the nearby dwarf elliptical galaxies NGC 185 and NGC 205, obtained from deep HST WFPC2 F555W and F814W images. Surface photometry was obtained using concentric annular apertures. Each concentric annular aperture was divided into eight sectors to derive the mean surface brightness and error.
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