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 http://arxiv.org/abs/1409.5597, 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:
- Mtot = 69144.5 M_sun
- L_V = 35547.1 L_V_sun
- M/L_V = 1.95 Msun/L_V_sun
- <m> = 0.495 Msun
- r_h = 3.14 pc
- r_eff = 1.43 pc
- N neutron stars = 130
- N black holes = 2
- Mass in remnants = 27176.4 Msun
We do the comparison in 3 steps:
- Step 1: Surface brightness profile + RVs
- Step 2: Surface brightness profile + RVs + PMs ('HST')
- 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.