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ParameterFile

You interact with CAMEL through a parameter file.
You will find examples of parameter files in the /par sub-directory.

On this page... (hide)

1. The Boltzmann Engine
2. The cosmological parameters you want to estimate.
3. Likelihoods
4. The nuisance parameters (associated to each likelihood)
5. External constraints, i.e., priors
6. Fitter options

1. The Boltzmann Engine

The engine is the Boltzmann code you want to use and the parameters associated.
For now, CAMEL is able to handle two Boltzmann solver:

CLASS (http://class-code.net)

engine=class

For CLASS you can do it with the keyword class which passes the next arguments as strings to the solver. Some parameters are mandatory. These include the following string parameters:

class     k_pivot               0.05
class     lensing               yes
class     sBBN\ file            bbn/sBBN.dat

For instance to define the non-cold-darkmatter setup to a degenerate massive neutrino with 0.06 eV (the upper limit in normal hierarchy measured from oscillation experiments) one may use:

class     N_ncdm                1
class     m_ncdm                0.06
class     N_eff                 2.046

Note that in class, N_eff corresponds to the pure radiation today (explaining why this is not the famous 3.046 value). You may ask why not passing these parameters as previously using the fix keyword. Well you can but this probably better decouples the variables from their environment (and avoids repeating unnecessary numbers in output files).

Note that you can also change the precision file (delivered in CAMEL):

precisionFile=class_pre/hpjul2.pre

PICO (https://sites.google.com/a/ucdavis.edu/pico)

engine=pico

See this page for more details on the different Boltzmann codes.

2. The cosmological parameters you want to estimate.

For instance, the 6 parameters of the ΛCDM model as shown below:

par   omega_b             cosm    0.2222938E-01      0.00027   0.017   0.027
par   omega_cdm           cosm    0.1198340E+00      0.0026    0.09    0.15
par   100*theta_s         cosm    0.1040856E+01      0.6E-04   1.0170  1.0617
par   tau_reio            cosm    0.7801007E-01      0.13E-01  0.01016 0.18221
par   log(10^10A_s)       cosm    0.3090333E+01      0.025     2.7     3.5
par   n_s                 cosm    0.9655817E+00      0.0070    0.9     1.1

The first column defines whether the parameter that is defined on the line should be fitted for (par keyword) or fixed to a specified value (fix).
The second keyword is the name of the cosmological parameter. Note that the name must follow the syntax of the Boltzmann engine. The above names reflects the one used in CLASS.
The keyword cosm(o) means that this is a physical parameter (by comparison with the nuisance parameters nui as described after)
The fourth column is a numerical value giving a rough estimate of the value of the parameter.
The fifth column gives a rough value of the expected error.
The sixth column gives the minimum value of the parameter. Values below the specified minimum value won't be explored by the likelihood function.
The seventh column gives the maximum value of the parameter. Values above the specified minimum value won't be explored by the likelihood function.

3. Likelihoods

Choose the likelihood you want to use among the available ones. CAMEL can use the clik format used for Planck official likelihoods (PLA). The code also includes likelihoods based on public data (as JLA, BAO or Hillipop).

The likelihoods available with CAMEL are:

CMB low-l (Planck likelihood Bflike)

clikfile=planck_data/low_l/bflike/lowl_SMW_70_dx11d_2014_10_03_v5c_Ap.clik

CMB high-l (Planck likelihood Plik)

clikfile=/afs/in2p3.fr/group/planck/plaszczy/clik_10.3/hi_l/plik/plik_dx11dr2_HM_v18_TT.clik

CMB lensing (Planck likelihood)

lensing_file=planck_data/lensing/smica_g30_ftl_full_pttptt.clik_lensing

CMB high-l (Hillipop)

HiLLiPOP=HiLLiPOP/DX11dHM_superExt_CO_TT.lik

CMB very-high-l (SPT)

SPT_Low =HighEll/SPT_low_plik.par
SPT_High=HighEll/SPT_high_2014.lik

CMB very-high-l (ACT)

ACT_equat=HighEll/ACT_equat.lik
ACT_south=HighEll/ACT_south.lik

SNIa (JLA)

JLA_SNIA_File=JLA/JLA.lik

BAO
- BAO 1D

BAOFile=BAO/BAO1D_new.lik

BAO 2D

BAO2DFile=BAO/Boss_anderson_dr11.lik

See this page for more details on the different likelihoods.

4. The nuisance parameters (associated to each likelihood)

The nuisance parameters depend on the data used for the likelihood function. They describe the instrument systematics or the astrophysical foregrounds residuals as parametrized in the likelihoods.

CMB low-l (bflike)

None

CMB high-l (PLIK)

par     A_planck            nui   0.1000366E+01      0.01       0.9     1.1 #ycal
par     A_cib_217           nui   0.6639331E+02      1          0       200 #OK Acib217
par     xi_sz_cib           nui   0.2910632E-01      .01        0       1   #xi_sz_cib
par     A_sz                nui   0.7107652E+01      1          0       10  #OK Atsz143
par     ps_A_100_100        nui   0.2513368E+03      10         0       400 #OK Aps100
par     ps_A_143_143        nui   0.3862939E+02      1          0       400 #OK Aps143
par     ps_A_143_217        nui   0.3311444E+02      1          0       400 #OK Aps143x217
par     ps_A_217_217        nui   0.9814552E+02      1          0       400 #OK Aps217
par     ksz_norm            nui   0.7336660E-03      1          0       10  #OK Aksz
par     gal545_A_100        nui   0.7384000E+01      .2         0       50  #OK AdustTT100
par     gal545_A_143        nui   0.9009943E+01      9.41       0       50  #OK AdustTT143
par     gal545_A_143_217    nui   0.1738677E+02      19.69      0       100 #OK AdustTT143x217
par     gal545_A_217        nui   0.8201474E+02      82.4       0       150 #OK AdustTT217
par     calib_100T          nui   0.9978837E+00      .2         0       3   #OK c100
par     calib_217T          nui   0.9958622E+00      .2         0       3   #OK c217
fix     cib_index           nui    -1.3              .2         -5      5   #OK ncib

CMB high-l (Hillipop)

par   A_planck     	  nui	  1		0.001	     0.9 	1.1
par   c0		  nui     0.		0.001     -0.05   0.05
par   c1		  nui     0.		0.001     -0.05   0.05
fix   c2		  nui     0.		0.001     -0.05   0.05
par   c3		  nui     0.		0.001     -0.05   0.05
par   c4		  nui     0.004		0.001     -0.05   0.05
par   c5		  nui     0.004		0.001     -0.05   0.05
par   Aps100x100          nui     2.5E-04	1E-05     0.0     0.1
par   Aps100x143          nui     1.1E-04	7E-06     0.0     0.1
par   Aps100x217          nui     9.9E-05	6E-06     0.0     0.1
par   Aps143x143          nui     4.7E-05	2E-06     0.0     0.1
par   Aps143x217          nui     3.1E-05	3E-06     0.0     0.1
par   Aps217x217          nui     7.6E-05	6E-06     0.0     0.1
par   Asz                 nui     1		0.1       0.0     10
par   Acib                nui     1.		0.1       0.0     10
par   AdustTT		  nui	  1	        0.1	  0.0     2
par   AdustPP		  nui	  1.00        0.1	  0.0     2
par   AdustTP		  nui	  1.00        0.1	  0.0     2
par   Aksz                nui     1.00        1.0	  0.0     10
par   Aszxcib             nui     1.00        1.0	  0.0     10

CMB very-high-l

The likelihood for very high multipoles share the same additional foregrounds with the high-l likelihood: for Hillipop

par   Asz                 nui     1		0.1       0.0     10
par   Acib                nui     1.		0.1       0.0     10
par   Aksz                nui     1.            1.0	  0.0     10
par   Aszxcib             nui     1.            1.0	  0.0     10

or for Plik

par     A_cib_217           nui   0.6639331E+02      1          0       200 #OK Acib217
par     xi_sz_cib           nui   0.2910632E-01      .01        0       1   #xi_sz_cib
par     A_sz                nui   0.7107652E+01      1          0       10  #OK Atsz143
par     ksz_norm            nui   0.7336660E-03      1          0       10  #OK Aksz

SPT (high latitude)

par     SPT_high_95_cal         nui     0.9961  0.002   0.9     1.1
par     SPT_high_150_cal        nui     1.002   0.002   0.9     1.1
par     SPT_high_220_cal        nui     1.015   0.002   0.9     1.1
par     SPT_high_Aps_95x95      nui     7.425   0.01    0.1     50
par     SPT_high_Aps_95x150     nui     5.147   0.01    0.1     50
par     SPT_high_Aps_95x220     nui     8.8     0.01    0.1     50
par     SPT_high_Aps_150x150    nui     6.649   0.01    0.2     50
par     SPT_high_Aps_150x220    nui     14.15   0.01    1.5     50
par     SPT_high_Aps_220x220    nui     36.07   0.01    3       200
fix     SPT_ADust               nui     1

SPT-low

par     SPT_low_Aps             nui             20.32           0.01		1.              60
par     SPT_low_cal             nui             1.00		0.01            0               2

par     ACT_equat_148_cal       nui     0.9991  0.002   0.9     1.1
par     ACT_equat_220_cal       nui     1.013   0.002   0.9     1.1
par     ACT_equat_ADust         nui     1.719   0.01    0.05    10
par     ACT_equat_Aps_148x148   nui     7.159   0.01    0.1     50
par     ACT_equat_Aps_148x220   nui     20      0.01    0.1     50
par     ACT_equat_Aps_220x220   nui     60      0.01    10      150

par     ACT_south_148_cal       nui     1.007   0.002   0.9     1.1
par     ACT_south_220_cal       nui     1.032   0.002   0.9     1.1
par     ACT_south_ADust         nui     1.3     0.01    0.05    10
par     ACT_south_Aps_148x148   nui     9       0.01    0.1     50
par     ACT_south_Aps_148x220   nui     16.29   0.01    0.1     50
par     ACT_south_Aps_220x220   nui     60      0.01    10      150

CMB lensing

None

SNIa (JLA)

par       Mabs          nui     -19.04          .03             -19.25          -18.85
par       alpha         nui     0.141           .01             0.10            .18
par       beta          nui     3.101           0.1             2.5             3.7
par       DeltaM	nui     -.076           0.03            -.13            -0.01

Refer to the previous section for a detailed description of the columns. Note that the nui keyword (in column 3) is used to define nuisance parameters.
See this page for more details on the different likelihoods.

5. External constraints, i.e., priors

Some assumptions can be used beforehand to apply on any fitted parameter. They can be specified as follows:

gauss1     parname       value sigma

gauss1 will constrain the parameter parname to value within sigma standard deviation.

In particular, for the likelihoods available, we recommend using the following priors for the nuisance parameters:

#Plik priors
gausssum2  A_sz    ksz_norm   1.6 1. 9.5 3
gauss1     calib_100T       0.9990004 0.001
gauss1     calib_217T       0.99501   0.002
gauss1     gal545_A_100     7         2
gauss1     gal545_A_143     9         2
gauss1     gal545_A_143_217 21        8.5
gauss1     gal545_A_217     80        20
gauss1     A_planck         1         0.0025

#Hillipop priors
gauss1    AdustTT	1	0.2
gauss1    Asz		1	0.2
gauss1    Acib		1	0.2
gauss1    A_planck	1	0.0025
gauss1    c0		0	2e-3
gauss1	  c1		0	2e-3
gauss1	  c3		0	2e-3 
gauss1	  c4		0.0025	2e-3 
gauss1	  c5		0.0025	2e-3

#SPT priors
gauss1 SPT_high_95_cal  1.01 .01
gauss1 SPT_high_150_cal 1.01 .01
gauss1 SPT_high_220_cal 1.01 .02

6. Fitter options

Some options can be given to CAMEL depending on the statistical method you want to use. This includes iteration and tolerance parameters for MINUIT:

nitermax=50000
set_stra=2
set_tol=0.00001

But also output options:

remove_cosmo_limits=false
doHesse=true

See Main.StatisticalMethods for more information on the different statistical methods available and their options.

Cosmological Analysis with Minuit Exploration of the Likelihood