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--- tests:collision:gc1_archive [2014/10/22 14:59] – v.henault-brunet
+++ tests:collision:gc1_archive [2022/10/24 12:26] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
-====== Gaia Challenge 1 ======
+====== GC I ======
+===== Challenge 1: Equal mass clusters in a tidal field =====
-==== Preliminary results from Gaia Challenge 1 workshop ====
-=== Challenge 1 ====
 ^ ^ ^  All Stars ^^^^ 1000 stars^^^^
@@ Line 21: / Line 18: @@
 |  | $f_\nu$              | $0.259$ |           | $8.225$ |           |
-Plots
 ^ Cluster  ^ Plots ^
 |1 | Isotropic King vs $f_\nu$ |{{:data:ch1_1_new.png?250}} |
@@ Line 28: / Line 24: @@
 |  | Anisotropic Michie King   | {{:data:t1c2.png?250}} |
 |3 | Isotropic King vs $f_\nu$ |   {{:data:collisional_Ch1_3.png?250}}|
 |  | Anisotropic Michie King   | {{:data:t1c3.png?250}} |
+===== Challenge 2: Isolated models with stellar evolution =====
+Active participants: Alice Zocchi, Antonio Sollima, Matt Walker, ,  Laura Watkins, Glenn van de Ven, Pascal Steger?
+How important is the effect of mass segregation?
+  - How correct is the assumption of energy equipartition (i.e. multi-mass King models)?
+  - How different are the fits when considering: 1.) all stars, 2.) only visible stars
+  - Is it better to consider luminosity weighted profiles, or number density profiles?
+  - How much can we do with 2 velocity components instead of 1 (i.e. with Gaia data)?
-===== Other possible challenges =====
-==== Pal 5 model from Andreas Kuepper in streams section ====
+==== Description of the models: ====
-Same analyses as in Challenge 2 and 3, but with cluster on eccentric orbit and "polluting" stars from tidal tails. The models posted in the streams section were not evolved with stellar evolution and for a Hubble time, but Andreas sent me files for that. Will upload them if there is interest.
+(Based on simulations ran by Mark Gieles, not published)\\
+Here we consider 2 clusters:
-==== Models with initial rotation ====
+  - IC: Cored gamma/eta model, N = 1e5, Kroupa (2001) mass function between 0.1-100 Msun.
-Different models with angular momentum are within the group: collapsing spheres, cold fractal collapse, cluster mergers.
+  - No primordial binaries, no central black hole, no tidal.
+  - Stellar evolution and mass-loss according to Hurley et al. (2000, 2002)
+  - Two values for the metallicity of the stars: [Fe/H] = -2.0 and 0.0 (solar)
+Below are 2 snapshots at an age of roughly 12 Gyr. The columns are:
-=== Collapse of homogeneous spheres with angular momentum ===
+^ $m$    ^ $X$ ^ $Y$ ^ $Z$ ^ $V_x$ ^ $V_y$ ^ $V_z$ ^ $\log T_{EFF}$ ^ $M_{bol}$ ^ KSTAR ^
-Below snapshots of 3 cold(ish) collapses of homogeneous spheres with angular momentum. Initial virial ratios and angular momentum were taken from the 3 models described in Gott (1972). The models contain 2e5 stars, a Kroupa IMF between 0.1 and 100 Msun and snapshots are at t=30 [NBODY]. The amount of rotation is quantified with Peebles $\lambda$ parameter in the title:
+| [Msun] | [PC] |||  [km s-1]  ||| [K] |[MAG]|
-  - {{:data:rot_collapse_lam0.127.gz}} NEW! Tuesday August 20
+KSTAR is the stellar type and can be between 0 and 22 and the meanings are given below in the Appendix.
-  - {{:data:rot_collapse_lam0.168.gz}} NEW! Tuesday August 20
-  - {{:data:rot_collapse_lam0.212.gz}} NEW! Tuesday August 20
-[[http://personal.ph.surrey.ac.uk/~mg0033/movies/lam212.avi|visualisation]]
+  - {{:ETA3_SEV_N100K_ISO_FEH-0.0_T12656.gz}}
+  - {{:ETA3_SEV_N100K_ISO_FEH-2.0_T12892.gz}}
-=== Mergers ===
+Cluster properties:
-Merger between 2 clusters of equal mass, equal containing 1e5 stars, a Kroupa IMF between 0.1 and 100 Msun. The initial orbit of the cluster pair had zero energy and different angular momentum. The
-  - {{:data:rot_merger_lam0.128.gz}} NEW! Tuesday August 20
-For both collapse and mergers collapse contain:
+^ Cluster ^ Mass      ^ Radii ^^^^ rms velocities^^^^
+|    | |$r_{\rm h}$(3D,M)|$r_{\rm h}$(2D,L)|$r_{\rm h}$(2D,M)|$r_{\rm h}$(2D,N)|$v_{\rm rms}$|$v_{\rm rms}$(Giants)|
+|    |[$M_\odot$]     |      [pc]       |     [pc]        | [pc]    | [pc] |[km/s]|[km/s]|
+|1   |$3.34\times10^4$| 9.73            | 3.33            | 7.27    | 10.0 | 2.39 | 2.52|
+|2   |$3.33\times10^4$| 10.9            | 4.71            | 8.20    | 11.3 | 2.30 | 2.67|
-^ $M$ ^ $X$ ^ $Y$ ^ $Z$ ^ $V_x$ ^ $V_y$ ^ $V_z$ ^
+Density distribution for cluster 2: {{:data:collisional_rho.png?250}}
-| [$M_\odot$]  | [NBODY] |||    [NBODY]   |||
-=== Collapse of non-homogeneous spheres with angular momentum ===
+==== (PRELIMINARY) RESULTS: ====
-(Based on simulations ran by Anna Lisa Varri, see [[http://adsabs.harvard.edu/abs/2013AAS...22211703G|Ref1 ]] [[http://adsabs.harvard.edu/abs/2013AAS...22211702T|Ref2]])
+^ ^ ^  All Stars ND ^^^ All Stars Mass^^^ All Stars Lum^^^
+^ Cluster ^ Method             ^$M$^$r_{\rm h}$^$R_{\rm h}$^$M$^$r_{\rm h}$^$R_{\rm h}$^$M$^$r_{\rm h}$^$R_{\rm h}$^$R_{\rm h}$
+|1 | isotropic King            | $3.17*10^4$  | $11.76$ | $8.67$ | $3.03*10^4$ | $9.06$ | $6.66$ | $3.07*10^4$ | $8.63$ | $6.39$ |
+|  | Multi-mass King           |   |           |    |           |
+|  | $f_\nu$                   | $3.80*10^4$  | $12.88$ | $9.66$ | $3.54*10^4$ | $9.00$ | $6.73$ | $3.08*10^4$ | $3.31$ | $2.48$ |
+|  | Parametric Jeans          |   |           |    |           |
+|  | Discrete Jeans            |   |           |    |           |
+|2 | Isotropic King            | $3.07*10^4$  | $14.27$ | $10.55$ | $2.72*10^4$ | $11.69$ | $8.32$ | $2.93*10^4$ | $11.13$ | $8.19$ |
+|  | Multi-mass  King          |   |           |    |           |
+|  | $f_\nu$                   | $3.71*10^4$ | $14.66$ | $11.03$ | $3.66*10^4$ | $11.07$ | $8.26$ | $3.30*10^4$ | $6.08$ | $4.50$ |
+|  | Parametric Jeans          |   |           |    |           |
+|  | Discrete Jeans            |   |           |    |           |
-Below snapshots of two cold(ish) collapses of isolated spheres with N=64k, equal mass stars, non-homogeneous initial density distribution (fractal dimension D = 2.8, 2.4, as in the file name), and approximate solid-body rotation. The configurations are characterized by the same **initial** values of virial ratio and global angular momentum as in the homogeneous case #3 (with  $\lambda=0.212$). The simulations have been performed with [[http://www.sns.ias.edu/~starlab/|STARLAB]] and the snapshots are taken at T=20 [NBODY].
-   - {{:data:rot_collapse_fracd2.4.gz}} NEW! Tuesday August 20
-   - {{:data:rot_collapse_fracd2.8.gz}} NEW! Tuesday August 20
-The file header contains: N, T, coordinates and velocities of the center of mass. The file format is as follow:
+===== Challenge 3: Clusters in tidal fields with stellar evolution =====
+(Simulations ran and kindly made available by Holger Baumgardt)\\
-^ $ID$ ^ $M$ ^ $X$ ^ $Y$ ^ $Z$ ^ $V_x$ ^ $V_y$ ^ $V_z$ ^
+Here we consider 2 clusters which are slightly more realistic:
-|  | [NBODY]  | [NBODY] |||    [NBODY]   |||
+  - IC: King (1966) W_0 = 5 model, N = 131072, Kroupa (2001) mass function between 0.1-15 Msun (no black-holes).
+  - No primordial binaries, no central black hole, circular orbit in logarithmic halo with V = 220 km/s.
+  - Z = 0.001
+  - Stellar evolution and mass-loss according to Hurley et al. (2000, 2002)
+  - Two Galactocentric radii: 8.5 kpc and 15 kpc.
-==== More ideas (but no mock data for these yet) ====
-  - What is the effect of binary stars?
+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.
-  - Is there a dynamical "smoking gun" for an intermediate mass black hole?
+  - {{:data:W05_N131K_RG8.5_FEH-0.0_T10.gz}} UPDATED! Thursday August 22
+  - {{:data:W05_N131K_RG8.5_FEH-0.0_T100.gz}} UPDATED! Thursday August 22
+  - {{:data:W05_N131K_RG8.5_FEH-0.0_T1000.gz}} UPDATED! Thursday August 22
+  - {{:W05_N131K_RG8.5_FEH-0.0_T12000.gz}}
+  - {{:data:W05-N131K_RG15_FEH-0.0.T10.gz}} NEW! Tuesday August 20
+  - {{:data:W05-N131K_RG15_FEH-0.0.T100.gz}} NEW! Tuesday August 20
+  - {{:data:W05-N131K_RG15_FEH-0.0.T1000.gz}} NEW! Tuesday August 20
+  - {{:W05_N131K_RG15_FEH-0.0_T12000.gz}}
+Questions are the same as in Challenge 2, and in addition:
+  - Is the presence of the tidal field affecting the velocity anisotropy in the outer parts?
+  - Can the mass segregation be reproduced by multi-mass King models?
+ Example of the velocity dispersion difference of different mass components:
+{{:data:sig2ratio.png?250}}
+Different models to fit:
+  - $f_\nu$
+  - Multi-mass King
+  - Discrete "Jeans like" modelling
+  - DF fitting (Mark W?)
+==== Results: ====
+Using all stars:
+^ ^ ^ ^  All Stars ^^^^ 1000 stars^^^^
+^ Cluster ^ Snapshot ^ Method             ^$M$^$r_{\rm c}$^$r_{\rm h}$^$r_{\rm J}$ ^ $M$^$r_{\rm c}$^$r_{\rm h}$^$r_{\rm J}$^
+|1 | 1 | Isotropic King   |  |         | |           |
+|  | 1 | Multimass Michie King      |         | |   |           |
+|  | 1 | $f_\nu$              |  |           | |           |
+|  | 1 | Discrete modelling        |   |           |           |           |
+|1 | 2 | Isotropic King   |  |         | |           |
+|  | 2 | Multimass Michie King      |         | |   |           |
+|  | 2 | $f_\nu$              |  |           | |           |
+|  | 2 | Discrete modelling        |   |           |           |           |
+|1 | 3 | Isotropic King   |  |         | |           |
+|  | 3 | Multimass Michie King      |         | |   |           |
+|  | 3 | $f_\nu$              |  |           | |           |
+|  | 3 | Discrete modelling        |   |           |           |           |
+|1 | 4 | Isotropic King   |  |         | |           |
+|  | 4 | Multimass Michie King | $2.118$ |  | $11.353$ |  |
+|  | 4 | $f_\nu$              |  |           | |           |
+|  | 4 | Discrete modelling        |   |           |           |           |
+|2 | 1 | Isotropic King   |  |         | |           |
+|  | 1 | Multimass Michie King      |         | |   |           |
+|  | 1 | $f_\nu$              |  |           | |           |
+|  | 1 | Discrete modelling        |   |           |           |           |
+|2 | 2 | Isotropic King   |  |         | |           |
+|  | 2 | Multimass Michie King      |         | |   |           |
+|  | 2 | $f_\nu$              |  |           | |           |
+|  | 2 | Discrete modelling        |   |           |           |           |
+|2 | 3 | Isotropic King   |  |         | |           |
+|  | 3 | Multimass Michie King      |         | |   |           |
+|  | 3 | $f_\nu$              |  |           | |           |
+|  | 3 | Discrete modelling        |   |           |           |           |
+|2 | 4 | Isotropic King   |  |         | |           |
+|  | 4 | Multimass Michie King      |         | |   |           |
+|  | 4 | $f_\nu$              |  |           | |           |
+|  | 4 | Discrete modelling        |   |           |           |           |
+Plots
+^ Cluster  ^ Plots ^
+|1 | 1 | Isotropic King vs $f_\nu$ | |
+|  | 1 | Multimass Michie King   | |
+|  | 1 | Discrete modelling        | |
+|1 | 2 | Isotropic King vs $f_\nu$ | |
+|  | 2 | Multimass Michie King   | |
+|  | 2 | Discrete modelling        | |
+|1 | 3 | Isotropic King vs $f_\nu$ | |
+|  | 3 | Multimass Michie King   | |
+|  | 3 | Discrete modelling        | |
+|1 | 4 | Isotropic King vs $f_\nu$ | |
+|  | 4 | Multimass Michie King   |{{:data:t3c1.png?250}} |
+|  | 4 | Discrete modelling        | |
+|2 | 1 | Isotropic King vs $f_\nu$ | |
+|  | 1 | Multimass Michie King   | |
+|  | 1 | Discrete modelling        | |
+|2 | 2 | Isotropic King vs $f_\nu$ | |
+|  | 2 | Multimass Michie King   | |
+|  | 2 | Discrete modelling        | |
+|2 | 3 | Isotropic King vs $f_\nu$ | |
+|  | 3 | Multimass Michie King   | |
+|  | 3 | Discrete modelling        | |
+|2 | 4 | Isotropic King vs $f_\nu$ | |
+|  | 4 | Multimass Michie King   | |
+|  | 4 | Discrete modelling        | |
+==== Results: ====
+Velocity dispersion for different mass species: the multi-mass King models assume that the product $m\sigma_K^2$= constant. The parameters $\sigma_K$ is not exactly the velocity dispersion.