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BVRI-Halpha surface photometry of peculiar ring galaxies. I. HRG 2302

M. L. M. Myrrha·L. P. R. Vaz·M. Faúndez-Abans·M. de Oliveira-Abans·D. S. L. Soares
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Abstract

Detailed BVRI-Halpha photometry has been obtained for the ring galaxy HRG 2302. This is probably a still interacting system which shows two principal components: the target, which is a knotted ringed-disk, and the intruder, an elongated galaxy with two substructures probably caused by the interaction. The existence of H II emission regions is suggested by Halpha images and medium dispersion spectra of the three brightest parts of this system. Analysis of a color-color diagram suggests recent star formation, in agreement with the behavior of interacting galaxies with nuclear emission. HRG 2302 has been previously classified as a Polar Ring galaxy (Faundez-Abans & de Oliveira-Abans 1998a), but we have reclassified it as Elliptical-Knotted, based on the morphological substructures found. This work reveals, for the first time, the existence of at least 15 fainter galaxies in the field within ~4 arcmin around HRG 2302, giving positions and integrated standard magnitudes for all of them.

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M. L. M. Myrrha, L. P. R. Vaz, M. Faúndez-Abans, M. de Oliveira-Abans, D. S. L. Soares. 1999-09-24. BVRI-Halpha surface photometry of peculiar ring galaxies. I. HRG 2302. https://arxiv.org/abs/astro-ph/9909425

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