KITP: globular orbits

and we ponder the orbits of globulars, red and blue,
what does this tell us about where and when they formed
and where and when they get eaten

β(r) = 1 - σ²_φ/&sigma²₂
- and be careful with your factors of 2 and φ here...

I just like this picture

ah, if we only knew that we would know something

in theory, we can look at the globular distribution - radial as we must, kinematic if we could
and hence infer whence they came at high z, given ΛCDM models

if we ignore the baryons, which i embarrassing, since globulars are baryonic and don't have much dark matter, at least not in the middle
but i digress

dark matter is easier, so that is what we do first

so blue globulars come from around z ~ 12, at least for Milky Way like halos, to the extent they can be associated with the correct baryon mass substructure assembly and halo kinematics

like this

then they are on some orbit, radial depending on how halo contraction proceeded and violence of relaxation
then we get some dynamical friction and shocking from disk and bulge and of course internal relaxation and evaporation, and we lose some globulars.

viva via lactea

How many do we lose?
1%?
10%
50%?
90%?
99%?

yes, one of those.

Then of course there are red globulars.

Oy vey.