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arXiv · 1603.03595

MCG+08-22-082: A double core and boxy appearance dwarf lenticular galaxy as suspected to be a merger remnant

Mina Pak·Sanjaya Paudel·Youngdae Lee·Sang Chul Kim
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Abstract

We present a study on the dwarf lenticular galaxy MCG+08-22-082 (U141) located in the Ursa Major cluster, which is blue centered, double cored, and has a boxy appearance. Using publicly available data from the SDSS, we perform an analysis of structural and stellar population properties of the galaxy and the cores. We find that the light profile of U141 follows an exponential law. U141 has a brightness Mr = -16.01 mag, and an effective radius Re = 1.7 kpc. The boxiness parameter, a4/a, is mostly between 0 and -0.05 in the inner parts, reaching an extreme of about -0.1. Double cores are seen at the center of U141 and each of these cores has a stellar mass of ~10^6 M_sun and the separation between them is ~300 pc. Optical spectroscopy of these cores shows prominent emission in H_alpha suggesting ongoing star forming activities. We interpret these morphological properties to speculate that U141 is a merger remnant of two disk galaxies. Thus, we might have caught an intermediate stage of merging with the evidence of double cores in the center of the galaxy.

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Mina Pak, Sanjaya Paudel, Youngdae Lee, Sang Chul Kim. 2016-03-11. MCG+08-22-082: A double core and boxy appearance dwarf lenticular galaxy as suspected to be a merger remnant. https://doi.org/10.3847/0004-6256/151/6/141

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