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ESO 603-G21: A strange polar-ring galaxy

V. P. Reshetnikov·M. Faundez-Abans·M. de Oliveira-Abans
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Abstract

We present the results of B, V, R surface photometry of ESO603-G21 - a galaxy with a possible polar ring. The morphological and photometric features of this galaxy are discussed. The central round object of the galaxy is rather red and presents a nearly exponential surface brightness distribution. This central structure is surrounded by a blue warped ring or disk. The totality of the observed characteristics (optical and NIR colors, strong color gradients, HI and H_2 content, FIR luminosity and star-formation rate, rotation-curve shape, global mass-to-luminosity ratio, the agreement with the Tully-Fisher relation, etc.) shows that ESO603-G21 is similar to late-type spiral galaxies. We suppose that morphological peculiarities and the possible existence of two large-scale kinematically-decoupled subsystems in ESO603-G21 can be explained as being a result of dissipative merging of two spiral galaxies or as a consequence of a companion accretion onto a pre-existing spiral host.

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V. P. Reshetnikov, M. Faundez-Abans, M. de Oliveira-Abans. 2001-12-14. ESO 603-G21: A strange polar-ring galaxy. https://doi.org/10.1051/0004-6361%3A20011784

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