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arXiv · 2101.07002

The central region of the enigmatic Malin 1

Kanak Saha·Suraj Dhiwar·Sudhanshu Barway·Chaitra Narayan·Shyam N. Tandon
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Abstract

Malin 1, being a class of giant low surface galaxies, continues to surprise us even today. The HST/F814W observation has shown that the central region of Malin 1 is more like a normal SB0/a galaxy, while the rest of the disk has the characteristic of a low surface brightness system. The AstroSat/UVIT observations suggest scattered recent star formation activity all over the disk, especially along the spiral arms. The central 9" ($\sim 14$ kpc) region, similar to the size of the Milky Way's stellar disk, has a number of far-UV clumps - indicating recent star-formation activity. The high resolution UVIT/F154W image reveals far-UV emission within the bar region ($\sim 4$ kpc) - suggesting the presence of hot, young stars in the bar. These young stars from the bar region are perhaps responsible for producing the strong emission lines such as H$α$, [OII] seen in the SDSS spectra. Malin 1B, a dwarf early-type galaxy, is interacting with the central region and probably responsible for inducing the recent star-formation activity in this galaxy.

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Kanak Saha, Suraj Dhiwar, Sudhanshu Barway, Chaitra Narayan, Shyam N. Tandon. 2021-01-18. The central region of the enigmatic Malin 1. https://doi.org/10.1007/s12036-021-09715-5

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