User Tools

Site Tools


tests:collision:gc3:method_comp

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision
Previous revision
tests:collision:gc3:method_comp [2015/09/04 08:11] v.henault-brunettests:collision:gc3:method_comp [2022/10/24 12:28] (current) – external edit 127.0.0.1
Line 17: Line 17:
 MGE fit to surface brightness profile: MGE fit to surface brightness profile:
  
-{{tests:collision:gc3:sb_mge_fit.png}}+{{tests:collision:gc3:fit_sb.png}} {{tests:collision:gc3:fit_sb.pdf|PDF version}}
  
-{{tests:collision:gc3:sb_mge_fit.pdf|PDF version}}+{{tests:collision:gc3:sb_mge.png}} {{tests:collision:gc3:sb_mge.pdf|PDF version}} 
 + 
 +The fitted MGE profile has 8 Gaussian components. I assumed that I knew the distance (1.862 kpc) and fitted only the mass profile. I used the same set of Gaussians as for the surface brightness profile, but allowed their relative contributions to vary to best fit the underlying mass distribution of the cluster. 
 + 
 +Fitted mass and M/L profiles: 
 + 
 +{{tests:collision:gc3:fit_mass.png}} {{tests:collision:gc3:fit_mass.pdf|PDF version}} 
 + 
 +{{tests:collision:gc3:fit_ml.png}} {{tests:collision:gc3:fit_ml.pdf|PDF version}} 
 + 
 + 
 +Velocity dispersion profiles: 
 + 
 +{{tests:collision:gc3:fit_rv_disp.png}} {{tests:collision:gc3:fit_rv_disp.pdf|RV PDF version}} 
 + 
 +{{tests:collision:gc3:fit_pmx_disp.png}} {{tests:collision:gc3:fit_pmx_disp.pdf|PMx PDF version}} 
 + 
 +{{tests:collision:gc3:fit_pmy_disp.png}} {{tests:collision:gc3:fit_pmy_disp.pdf|PMy PDF version}}
  
  
 === Alice's single-mass DF model fit === === Alice's single-mass DF model fit ===
 +LIMEPY models (spherical, non-rotating) have been compared with surface brightness profile, line-of-sight velocity dispersion profile, and proper motions radial and tangential profiles.
 +
 +We considered 4 different cases, each time fitting on different parameters:
 +
 +(1) Isotropic case, assuming d = 1.862 kpc.
 +Fitting parameters: $W_0$, $g$, $M$, $r_h$, $M/L$.
 +
 +(2) Allowing for the presence of anisotropy, and assuming d = 1.862 kpc.
 +Fitting parameters: $W_0$, $g$, $M$, $r_h$, $M/L$, $r_a$. The best fit model has a very large anisotropy radius, and is actually isotropic.
 +
 +(3) Isotropic case, fitting also on the distance.
 +Fitting parameters: $W_0$, $g$, $M$, $r_h$, $M/L$, $d$.
 +
 +(4) Allowing for the presence of anisotropy, and fitting also on the distance.
 +Fitting parameters: $W_0$, $g$, $M$, $r_h$, $M/L$, $r_a$, $d$. The best fit model has a very large anisotropy radius, and is actually isotropic. [The contours below refer to this fit]
 +
 +[$W_0 =$ concentration of the models, $g =$ truncation parameter, $M =$ total mass of the cluster, $r_h =$ half-mass radius, $M/L =$ mass-to-light ratio, $r_a =$ anisotropy radius, $d$ = distance of the cluster]
  
  
 {{tests:collision:gc3:fit_sm_az.png}} {{tests:collision:gc3:fit_sm_az.png}}
 {{tests:collision:gc3:fit_sm_triangle_az.png}} {{tests:collision:gc3:fit_sm_triangle_az.png}}
 +
 +=== Mark's multi-mass DF model fit ===
 +7 parameter multi-mass fit to M4 data:
 +{{tests:collision:gc3:m4_mm_lt.png}}
 +
 +Results:
 +{{tests:collision:gc3:m4_mm_sb.png}}
 +{{tests:collision:gc3:m4_mm_kin.png}}
 +{{tests:collision:gc3:m4_mm_ml.png}}
tests/collision/gc3/method_comp.1441354317.txt.gz · Last modified: 2022/10/24 12:28 (external edit)