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arXiv · 2605.29618

A New Cartwheel-like Collisional Ring Galaxy

Vladimir P. Reshetnikov·Sergey S. Savchenko·Alexander A. Marchuk·Ilia V. Chugunov·Matvey D. Kozlov·Dmitry I. Makarov·Aleksandra V. Antipova·Anastasia M. Sypkova
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Abstract

We report the discovery of a new Cartwheel-type collisional ring galaxy, PGC\,1112751, which we named ``Eridanus Wheel'' (EW). Such systems result from head-on collisions between galaxies and are of considerable interest as laboratories for studying star formation in propagating density waves and the response of the star-gas disk of galaxies to strong external perturbations. During a systematic visual inspection of fields from the DESI Legacy Imaging Surveys, we identified a galaxy at a redshift of $z=0.0856$ whose morphology closely resembles that of the famous Cartwheel Galaxy. EW exhibits a well-defined inner ring and a more diffuse outer ring, with so-called ``spokes'' visible in the region between them. The ring galaxy and its possible intruder are connected by a faint optical bridge. The projected distance between the centers of the galaxies is about 60 kpc. Using data from the DESI Legacy Surveys, we performed a photometric study of galaxies in the $griz$ filters. We conclude that the Eridanus Wheel is a giant late-type galaxy with a strong radial color gradient, whose observed morphology is most likely explained by a relatively recent head-on collision with an early-type galaxy. The further evolution of this object will most likely lead to the formation of a galaxy with a low surface brightness disk.

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Vladimir P. Reshetnikov, Sergey S. Savchenko, Alexander A. Marchuk, Ilia V. Chugunov, Matvey D. Kozlov, Dmitry I. Makarov, Aleksandra V. Antipova, Anastasia M. Sypkova. 2026-05-28. A New Cartwheel-like Collisional Ring Galaxy. https://arxiv.org/abs/2605.29618

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