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Isolated galaxies and AMIGA

Galaxy evolution is a tug of war between the nature of the galaxy (morphology, mass, etc) and nurturing environment of the galaxy (major or minor mergers, ram stripping, etc) and to understand it, we need to understand when nature rules over nurture or otherwise. An interesting way to resolve this question is to study isolated galaxies - isolated in the sense that there are hardly any galaxies in their vicinity. The qualitative 'hardly any' was quantified to create the Catalog of Isolated Galaxies (in 1973) and then revised by the AMIGA people for a more up-to-date study. Understanding the evolution of isolated galaxies inherently tells us more about the role that the nature of the galaxy plays in it's evolution.

Today, I was reading up on some interesting papers by the AMIGA people, all three on the HI (neutral Hydrogen) profiles of select isolated galaxies. The three papers can be found here, here and here. I came across this survey recently and only today, as I was revisiting the page, did I realize that studying the isolated galaxies in HI would be interesting, as HI extends further out than the stars in a galaxy. HI observations help discover tidal debris from galactic interactions and inactive regions of the galaxy that aren't forming stars. The only thing is that the telescopes used in the aforementioned studies, VLA, EVLA and GMRT, still aren't as good as optical telescopes are in terms of spatial resolution. I don't exactly know if we're missing out on something big because of the coarser data in HI but higher resolution data from the ASKAP/BETA/SKA shouldn't hurt.

My weekend plans are to look at some of the other papers by the collaboration on star formation, lopsidedness in HI emission line profiles and so on. I think this is what I would like to work on for the time being - faint galaxies and ultra diffuse objects in HI. I would love to work on a computational project. If not look for them and study them in radio. If not radio, then in optical. I guess time will tell. As long as I put in the effort from my side.

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