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SRH
2018-Aug-10, 05:56 PM
Where do we find supernovae?

Are they in the spiral arms? Near black holes? In the galactic halo?
In globular clusters? Away from galaxies? In galactic jets?
If in the spiral arms, are they closer to the galactic center, or closer to the edge?
Also, there are different types of supernovae, so please lmk if certain types are found in certain places.
(Also, I'm looking for where we actually have observed supernovae rather than where we would find them theoretically)
Lastly, any reason why there is so little info on the internet as to where they are found?

Thanks.

ronin
2018-Aug-10, 06:11 PM
Not sure of the radial distribution (but would think it's based on stellar population rather than radial region) but I believe that most do occur close to, or in the galactic plane.

KaiYeves
2018-Aug-10, 06:49 PM
You just have to get lucky. Check your local thrift store. ;-)

schlaugh
2018-Aug-10, 07:03 PM
Try googling for "Supernovae locations". You'll get a number of hits, including this site: https://sne.space/statistics/host-galaxies/

A quick read of the data (more than 16,000 entries) shows that the vast, vast majority occurred outside the Milky way.

Or did you want to know only about the SN that have been recorded in our own back yard, so to speak?

trinitree88
2018-Aug-10, 09:05 PM
Where do we find supernovae?

Are they in the spiral arms? Near black holes? In the galactic halo?
In globular clusters? Away from galaxies? In galactic jets?
If in the spiral arms, are they closer to the galactic center, or closer to the edge?
Also, there are different types of supernovae, so please lmk if certain types are found in certain places.
(Also, I'm looking for where we actually have observed supernovae rather than where we would find them theoretically)
Lastly, any reason why there is so little info on the internet as to where they are found?

Thanks.

SRH Supernovae occur in a sense, unexpectedly in the periphery of galaxies. You'd think that most of the gas and dust occur in the luminous galactic bulge, so that's where most of the supernovae would be. But, it takes a big star to make a supe, and where the gas/dust density is high, lots of smaller stars form. So, in the galactic periphery, where the density is lower, fewer but bigger stars form, and they end up more often as supernovae. look at images of supernovae seen, and you'll notice an unusually high number on the edges. pete

StupendousMan
2018-Aug-12, 02:33 AM
Where do supernovae occur? Well, one way to answer the question is "where do the progenitors of supernovae live?" Let's try to answer _that_ question.

One can divide supernovae into two classes: those which form when a young, massive star runs out of fuel in its core, and those which are created when, in a binary star system containing an ordinary star and a white dwarf, the white dwarf accretes enough material to reach about 1.4 solar masses, setting off a runaway nuclear reaction. If you're looking for the core-collapse variety, you need to find a stars which are young (less than 5 or 10 Myr) and massive (more than 8 solar masses or so at birth). In other words, you need to look at a region of star formation. These are most common in the disks of spiral galaxies, and in irregular galaxies, in and around giant clouds of gas.

On the other hand, if you are looking for the white-dwarf-in-a-binary variety, you can find them pretty much anywhere. The stars in these binary systems can have relatively small masses, and they must be pretty old; at least, oh, 2 or 3 Gyr, long enough for one of the two stars to evolve into a white dwarf. These supernova progenitors can occur in any type of galaxy, and in any location within a galaxy.

That's the "theoretical" way to approach the problem. There's also the "observational" approach: if you have a telescope, and want to find supernovae, where should you look? The answer here is a bit different. Although supernovae (of the binary type, in particular) might be more common in regions where there are many stars -- such as the nuclei and bulges of galaxies -- they are also _harder to see_ in such densely packed regions: they blend in. It's easier to notice a new star if you are looking in an area which is largely empty. That means looking in the outskirts of a galaxy might be more productive than focusing on the very center -- even if more supernovae might be blowing up in that center.

This is a complicated question, and the answer will depend on exactly how you are asking it. I've spent many years working on and thinking about supernova searches, and I'd be happy to try to answer your questions. If you can make them more specific, it will be easier to provide answers.