====== GC2: Challenge 1 ======

===== Equal mass cluster in isolation and in a tidal field =====

**PI**: Alice Zocchi\\
**Other participants**: Mark Gieles, Vincent Henault-Brunet, Anna Lisa Varri, Antonio Sollima

Questions to address:
 
  - What is a suitable model to describe post-collapse clusters? We here consider 3 models:
        - Isotropic King (1966) 
        - Anisotropic Michie King 
        - $f_\nu$ [[http://adsabs.harvard.edu/abs/2003ApJ...584..729B|Bertin & Trenti (2003)]]; [[http://adsabs.harvard.edu/abs/2012A%26A...539A..65Z|Zocchi et al. (2012)]] 
  - How much does tangential anisotropy/retrograde rotation due to the tides matter?

The relevant snapshots from simulations of an isolated cluster and cluster within a tidal field are available in [[:tests:collision:mock_data|section A of the Mock data page]].

==== Comparison $f_\nu$ and isolated models ==== 
{{:4_450_ANIS.png?400}}

==== MCMC fit results to tidally limited models ==== 
===== Isotropic lowered isothermal models =====

{{:woolley.png?400}}{{:king.png?400}}{{:wilson.png?400}}

Example comparison between the 3 best-fit isotropic lowered isothermal spheres at different times:\\

{{:T100020.png?400}}{{:T350520.png?400}}

===== Anisotropic lowered isothermal models =====

Preliminary results for a Michie-style anisotropy fit:\\
{{:T100020_michie.png?400}}


===== Grids of Wilson, f_nu & rotating models =====

{{:grid_wilson.png}}