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KITP: collapse

By catdynamics on March 31, 2009.

This beautiful tuesday morning, Dave tutors us on relaxation and cluster core collapse.
Then it is party at Alison's place.

But, first, we go through thermodynamics of self-gravitating internally relaxed systems, multiple equilibria and general dimensionless solutions.



Open Cluster M7 (from Utahskies.org)



Globular cluster M4 (from Utahskies.org)
Core collapsed? Or not?



Globular cluster M15 (from Utahskies.org - ok actually hubblesite, but they had a scaled copy and I was on a roll)
Definitely core collapse, we think.

Seriously - there are more core collapsed or post-core collapsed clusters in the inner parts of the galaxy, as there should be, we think, maybe, depending on your definition.

M15 really almost certainly is in post-core collapse bounce, it is the only sensible way to explain PSR M15C and many other things about it.

But M4?
Which is it? A nice pre-collapse King model cluster?
Or a strongly modified way past post-core collapse cluster...?



ω Cen - absolutely positively definitely NOT a globular cluster

ω Cen is a nuisance, it violates all precepts about globulars, except how it looks,
ergo, it is not a globular
right?

Tags
astro
KITP

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