====== Challenge 2: Multi-mass clusters (no stellar evolution) ======

Data: Snapshots of simulations with a mass function. 
   - N <~= $10^5$, initial half-mass radius 2.25 pc, Henon isochrone model
   - Initial half-mass relaxation time =~ 350 Myr
   - no primordial binaries
   - Galaxy = singular isothermal sphere with Vc = 220 kms/s
   - Orbit: circular orbit at RG = 4 kpc

The $10^5$ stars were evolved with SSE (Hurley et al. 2000) to an age of 12 Gyr assuming a metallicity of [Fe/H] = -2 **before** the N-body model was run. Then an assumption was made about the retention fraction of neutron stars (NSs) and black holes (BHs). The snapshots contain all the stars within the tidal radius.

The properties of the snapshots are:

^ Name ^ f_retention NSs ^ f_rentention BHs ^ age ^ N(NS)_remaining ^ N(BH)_remaining ^
| cluster1 | 1 | 1 | 0.25 Gyr | 613 | 171 | 
| cluster1 | 1 | 1 | 0.5 Gyr  | 591 | 146 | 
| cluster1 | 1 | 1 | 0.75 Gyr | 559 | 134 | 
| cluster1 | 1 | 1 | 1 Gyr    | 548 | 119 | 
| cluster7 | 0.1 | 0.1 | 2 Gyr | 51 | 0 | 

Format of the snapshots are:

^ $KSTAR$ ^ $m$^ $X$ ^ $Y$ ^ $Z$ ^ $V_x$ ^ $V_y$ ^ $V_z$ ^ 
|   | [Msun] ||[pc]|    [km/s]   |||      

  - {{:data:gc1_1gyr.gz}} : 
  - {{:data:gc1_2gyr.gz}} : 
  - {{:data:gc1_3gyr.gz}} : 
  - {{:data:gc1_4gyr.gz}} : 
  - {{:data:gc1_5gyr.gz}} : 
  - {{:data:gc1_6gyr.gz}} : 
  - {{:data:gc1_7gyr.gz}} : 
  - {{:data:gc1_8gyr.gz}} : 
  - {{:data:gc1_9gyr.gz}} : 
  - {{:data:gc1_10gyr.gz}} : 
  - {{:data:gc1_11gyr.gz}} : 
No retention:
  - {{:data:gc2_1gyr.gz}} : 
  - {{:data:gc2_2gyr.gz}} : 
  - {{:data:gc2_3gyr.gz}} : 
  - {{:data:gc2_4gyr.gz}} : 
  - {{:data:gc2_5gyr.gz}} : 
  - {{:data:gc2_6gyr.gz}} : 
  - {{:data:gc2_7gyr.gz}} : 
  - {{:data:gc2_8gyr.gz}} : 
  - {{:data:gc2_9gyr.gz}} : 
  - {{:data:gc2_10gyr.gz}} : 
  - {{:data:gc2_11gyr.gz}} : 
  - {{:data:gc2_12gyr.gz}} : 

The definition of the stellar types (KSTAR) used in the ''NBODY6'' snapshots can be found in the [[:tests:collision:appendix|Appendix]].