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Challenge 4: M4

Method comparison: N-body model of M4

The mock data is a snapshots of large N-body simulation of the globular cluster M4 are available here. Full lists of data for all particles (mass, position, velocity, stellar type, stellar radius, V magnitude, B-V colour) are given at almost 400 instants in the lifetime of the model. The simulation is described in this paper, which should be cited when making use of this data.

We selected the snapshot at t = 12023.9 Myr. A distance modulus of 11.35 mag was adopted (i.e. D=1862.1 pc). The cluster properties are:

  1. Mtot = 69144.5 M_sun
  2. L_V = 35547.1 L_V_sun
  3. M/L_V = 1.95 Msun/L_V_sun
  4. <m> = 0.495 Msun
  5. r_h = 3.14 pc
  6. r_eff = 1.43 pc
  7. N neutron stars = 130
  8. N black holes = 2
  9. Mass in remnants = 27176.4 Msun

We do the comparison in 3 steps:

  1. Step 1: Surface brightness profile + RVs
  2. Step 2: Surface brightness profile + RVs + PMs ('HST')
  3. Step 3: Surface brightness profile + RVs + PMs ('HST' + 'Gaia')

(+ local mass function for methods allowing it).

DOWNLOAD NEW M4 MOCK DATA (updated 21/03/2017): All the mock data you will need (and more!) are available and bundled here. You can find a summary of the list of files in 'ReadMe_M4_mocks'.

Included are the surface brightness profile, line-of-sight dispersion profile and discrete velocities for RGB stars, HST-like PM dispersion profiles and discrete velocities, Gaia-like (end-of-mission) PM dispersion profiles and discrete velocities (for M4, bulge and halo-like backgrounds), number density profile for bright stars, and local mass function. Mass profiles and the M/L_V profiles (in projection and 3d) are also available. Predictions from best-fit models should be compared to the 3d M/L_V profile.

tests/collision/mock_data/challenge_4.txt · Last modified: 2018/03/16 21:16 by v.henault-brunet