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tests:collision:mock_data

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Mock data

Challenge 1: Single mass clusters, isolated and tidally limited.

Challenge 4: Comparison of mass modelling methods using N-body model of M4.

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

Data: Snapshots of simulations with a mass function.

  1. N <~= $10^5$, initial half-mass radius 2.25 pc, Henon isochrone model
  2. Initial half-mass relaxation time =~ 350 Myr
  3. no primordial binaries
  4. Galaxy = singular isothermal sphere with Vc = 220 kms/s
  5. 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]

No retention:

The definition of the stellar types (KSTAR) used in the NBODY6 snapshots can be found in the Appendix.

Challenge 3. Clusters in tidal fields with stellar evolution

(Simulations ran and kindly made available by Holger Baumgardt)

Here we consider 2 clusters which are slightly more realistic:

  1. IC: King (1966) W_0 = 5 model, N = 131072, Kroupa (2001) mass function between 0.1-15 Msun (no black-holes).
  2. No primordial binaries, no central black hole, circular orbit in logarithmic halo with V = 220 km/s.
  3. Z = 0.001
  4. Stellar evolution and mass-loss according to Hurley et al. (2000, 2002)
  5. Two Galactocentric radii: 8.5 kpc and 15 kpc.

Below are 2 snapshots at an age of roughly 10 Myr, 100 Myr, 1Gyr and 12 Gyr. The columns are the same as in Challenge 2.

  1. w05_n131k_rg8.5_feh-0.0_t10.gz UPDATED! Thursday August 22
  2. w05_n131k_rg8.5_feh-0.0_t100.gz UPDATED! Thursday August 22
  3. w05_n131k_rg8.5_feh-0.0_t1000.gz UPDATED! Thursday August 22
  4. w05-n131k_rg15_feh-0.0.t10.gz NEW! Tuesday August 20
  5. w05-n131k_rg15_feh-0.0.t100.gz NEW! Tuesday August 20
  6. w05-n131k_rg15_feh-0.0.t1000.gz NEW! Tuesday August 20

Final list of snapshots used in Sollima et al. in prep, columns are:

$m$ $X$ $Y$ $Z$ $V_x$ $V_y$ $V_z$ kstar logL logTeff
[Msun] [pc] [pc] [pc] [km/s [km/s] [km/s]

The definition of the stellar types (KSTAR) used in the NBODY6 snapshots can be found in the Appendix.

Appendix

Stellar types in ''NBODY''

There 23 possible stellar types (KSTAR) in NBODY

     0       Low main sequence (M < 0.7).
     1       Main sequence.
     2       Hertzsprung gap (HG).
     3       Red giant.
     4       Core Helium burning.
     5       First AGB.
     6       Second AGB.
     7       Helium main sequence.
     8       Helium HG.
     9       Helium GB.
    10       Helium white dwarf.
    11       Carbon-Oxygen white dwarf.
    12       Oxygen-Neon white dwarf.
    13       Neutron star.
    14       Black hole.
    15       Massless supernova remnant.
    19       Circularizing binary (c.m. value).
    20       Circularized binary.
    21       First Roche stage (inactive).
    22       Second Roche stage.
tests/collision/mock_data.1481896445.txt.gz · Last modified: 2022/10/24 12:26 (external edit)