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Neutral Hydrogen in Arp 158

Mansie G. Iyer·Caroline E. Simpson·Stephen T. Gottesman·Benjamin K. Malphrus
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Abstract

We present 21 cm observations of Arp 158. We have performed a study of the neutral hydrogen (HI) to help us understand the overall formation and evolution of this system. This is a disturbed system with distinct optical knots connected by a linear structure embedded in luminous material. There is also a diffuse spray to the southeast. The HI seems to be made up of three distinct, kinematically separate systems. Arp 158 bears a certain optical resemblance to NGC 520 (Arp 157), which has been identified as a mid-stage merger. From our 21 cm observations of Arp 158, we also see a comparable HI content with NGC 520. These similarities suggest that Arp 158 is also an intermediate stage merger.

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Mansie G. Iyer, Caroline E. Simpson, Stephen T. Gottesman, Benjamin K. Malphrus. 2004-05-20. Neutral Hydrogen in Arp 158. https://doi.org/10.1086/422731

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