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Method comparison: Jeans vs DF (Challenge #4)
Add plots here.
Laura's Discrete JAM
Axisymmetric Jeans models + discrete model-data comparison.
Assumptions:
- sphericity
- no rotation
- isotropic
- Gaussian velocity distributions
MGE fit to surface brightness profile:
Fitted mass profile:
Fitted M/L profile:
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]
