8.1. \(\tt jeansChi2\) executable

Jeans analysis with \(\chi^2\) minimisation.

8.1.1. \(\tt -r1\): binned analysis

For example, to run a binned Jeans analysis on \(\sigma_{\rm p}\) data from $CLUMPY/data/data_sigmap.txt, execute:

$ clumpy_jeansChi2 -r1 $CLUMPY/data/data_sigmap.txt output/chi2_binned.dat $CLUMPY/data/params_jeans.txt 0.05

using a numeric accuracy of 5%:

>>>>> Load $CLUMPY/data/params_jeans.txt
======== Binned Jeans analysis ========
 FLOATING-POINT NUMBERS ASSUMED ACCURATE TO 1e-08
 FCN=1.12954e-07 FROM MIGRAD    STATUS=FAILED        247 CALLS         248 TOTAL
                     EDM=2.56309e-06    STRATEGY= 1      ERR MATRIX NOT POS-DEF
  EXT PARAMETER                APPROXIMATE        STEP         FIRST
  NO.   NAME      VALUE            ERROR          SIZE      DERIVATIVE
   1  log10(rho_s)   8.80950e+00   2.07851e+00   0.00000e+00  -7.50619e-03
   2  log10(r_s)  -1.18420e+00   1.48070e+00   0.00000e+00  -3.42326e-03
   3  alpha        2.13991e-01   4.80224e-01  -0.00000e+00   3.10416e-04
   4  beta         3.00000e+00     fixed
   5  gamma        1.00000e+00     fixed
   6  beta_0       5.62379e-01   1.49796e+00   0.00000e+00  -3.39263e-03
   7  beta_infinity   0.00000e+00     fixed
   8  log10(r_a)   0.00000e+00     fixed
   9  eta          2.00000e+00     fixed
  10  DM_profile   0.00000e+00     fixed
  11  Rvir         1.00000e+03     fixed
  12  rho_s*       1.00000e+00     fixed
  13  r_s*         2.10000e-02     fixed
  14  alpha*       1.00000e+00     fixed
  15  beta*        3.00000e+00     fixed
  16  gamma*       0.00000e+00     fixed
  17  Light_profile   3.00000e+00     fixed
  18  R            1.00000e+02     fixed
  19  eps          5.00000e-02     fixed
  20  Aniso_profile   0.00000e+00     fixed
Statistical file saved in output/output.dat

The result, e.g., the best-fit value found for \(\sigma_{\rm p}\), can be visualised with the -s8 module of the \(\tt clumpy\) executable (see Section 7.4):

$ clumpy -s8 -D
$ clumpy -s8 -i clumpy_params_s8.txt --gSTAT_FILES=output/chi2_binned.dat
_images/jeansChi2_r1D.png

Fig. 8.1 -r1 output ROOT figure


8.1.2. \(\tt -r2\): unbinned bootstrap

$ clumpy_jeansChi2 -r2 $CLUMPY/data/data_vel.txt output/stat_bootstrap.dat $CLUMPY/data/params_jeans.txt 0.05 100

performs an Bootstrap (100 samples) unbinned Jeans analysis of the velocity data CLUMPY/data/data_vel.txt.

Note

Above example takes about 20 minutes to run.

The result can be again visualised with the -s8 module of the \(\tt clumpy\) executable (see Section 7.4):

$ clumpy -s8 -i clumpy_params_s8.txt --gSTAT_FILES=output/stat_bootstrap.dat
_images/jeansChi2_r2D.png

Fig. 8.2 -r2 output ROOT figures