====== Ideas for additional challenges ======

===== Weighing dark remnants using luminous stars =====
Explore how/if the mass function of dark remnants can be constrained from a limited set of observables, using mock data from N-body simulations. This could be part of Miklos’ project on Challenge 2. Provided that this works, we can then consider a direct application to real data (e.g. Gaia-ESO survey - some of us are members of the consortium).


===== Dark remnants & IMBH =====
Laura is applying her discrete Jeans modelling method to snapshots of N-body models that contain stellar-mass black holes. The idea is check if a concentration of dark remnants near the centre can be mistaken for an intermediate-mass black hole.


===== Pal 5 model from Andreas Kuepper in streams section =====

Same analyses as in Challenge 2 and 3, but with cluster on eccentric orbit and "polluting" stars from tidal tails. The models posted in the streams section were not evolved with stellar evolution and for a Hubble time, but Andreas sent me files for that. Will upload them if there is interest.

===== Models with initial rotation =====
Different models with angular momentum are within the group: collapsing spheres, cold fractal collapse, cluster mergers. 


==== Collapse of homogeneous spheres with angular momentum ====
Below snapshots of 3 cold(ish) collapses of homogeneous spheres with angular momentum. Initial virial ratios and angular momentum were taken from the 3 models described in Gott (1972). The models contain 2e5 stars, a Kroupa IMF between 0.1 and 100 Msun and snapshots are at t=30 [NBODY]. The amount of rotation is quantified with Peebles $\lambda$ parameter in the title: 

  - {{:data:rot_collapse_lam0.127.gz}} NEW! Tuesday August 20
  - {{:data:rot_collapse_lam0.168.gz}} NEW! Tuesday August 20
  - {{:data:rot_collapse_lam0.212.gz}} NEW! Tuesday August 20 
[[http://personal.ph.surrey.ac.uk/~mg0033/movies/lam212.avi|visualisation]]


==== Mergers ====
Merger between 2 clusters of equal mass, equal containing 1e5 stars, a Kroupa IMF between 0.1 and 100 Msun. The initial orbit of the cluster pair had zero energy and different angular momentum. The 
  - {{:data:rot_merger_lam0.128.gz}} NEW! Tuesday August 20

For both collapse and mergers collapse contain:

^ $M$ ^ $X$ ^ $Y$ ^ $Z$ ^ $V_x$ ^ $V_y$ ^ $V_z$ ^ 
| [$M_\odot$]  | [NBODY] |||    [NBODY]   |||        

==== Collapse of non-homogeneous spheres with angular momentum ====

(Based on simulations ran by Anna Lisa Varri, see [[http://adsabs.harvard.edu/abs/2013AAS...22211703G|Ref1 ]] [[http://adsabs.harvard.edu/abs/2013AAS...22211702T|Ref2]])

Below snapshots of two cold(ish) collapses of isolated spheres with N=64k, equal mass stars, non-homogeneous initial density distribution (fractal dimension D = 2.8, 2.4, as in the file name), and approximate solid-body rotation. The configurations are characterized by the same **initial** values of virial ratio and global angular momentum as in the homogeneous case #3 (with  $\lambda=0.212$). The simulations have been performed with [[http://www.sns.ias.edu/~starlab/|STARLAB]] and the snapshots are taken at T=20 [NBODY].

   - {{:data:rot_collapse_fracd2.4.gz}} NEW! Tuesday August 20
   - {{:data:rot_collapse_fracd2.8.gz}} NEW! Tuesday August 20

The file header contains: N, T, coordinates and velocities of the center of mass. The file format is as follow:

^ $ID$ ^ $M$ ^ $X$ ^ $Y$ ^ $Z$ ^ $V_x$ ^ $V_y$ ^ $V_z$ ^ 
|  | [NBODY]  | [NBODY] |||    [NBODY]   |||        


===== Mass modelling multiple-population GC with non-parametric method=====

Apply Pascal Steger's non-parametric method (developed for dwarf galaxies) to mock data from N-body simulation of globular cluster with two distinct chemical populations.

The data has the following format.
^ $m$ ^ $x$ ^ $y$ ^ $z$ ^ $v_x$ ^ $v_y$ ^ $v_z$ ^ population ^
|  [Msun] |  [pc]  |[pc]|[pc]| [km/s] | [km/s]   | [km/s]| [1 or 2] |      

  - {{:GC_mpop.dat}}


===== More ideas (but no mock data for these yet) =====

  - What is the effect of binary stars?
  - Is there a dynamical "smoking gun" for an intermediate mass black hole?