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jla module
Supernova likelihood for SDSS-II/SNLS3
Name: jla
File: cosmosis-standard-library/supernovae/jla_likelihood_v6/jla.so
Version: 6
Author(s):
- Marc Betoule
URL: http://supernovae.in2p3.fr/sdss_snls_jla/ReadMe.html
Cite:
Rules:
Assumptions:
- SALT2 used to fit light curves
- Akima interpolation between mu(z) samples
Explanation
This JLA code uses 731 supernovae from the JLA SDSS-II/SNLS3 sample
to get a likelihood of a given theory mu(z).
Systematic error propagation is done with a collection of separate
covariance matrices for the various light-curve parameters.
You can copy the standard parameters to use for this from demos/demo5.ini
This version (6) includes a simplified form of the likelihood with only one (instead of three) nuisance parameters.
We have not yet exposed this likelihood in cosmosis. The likelihood values of the original
JLA likelihood remain unchanged - there is no need to re-run any old chains with v6.
##Parameters
These parameters can be set in the module's section in the ini parameter file.
If no default is specified then the parameter is required.
Parameter | Description |
---|---|
data_dir | String; dir for other files. Use cosmosis-standard-library/supernovae/jla_v3/data (unless trying a different data set) |
data_file | String; dir for other files. Use jla_lcparams.txt (unless trying a different data set) |
scriptmcut | String; dir for other files. Use 10.0 |
mag_covmat_file | String; dir for other files. Use jla_v0_covmatrix.dat |
stretch_covmat_file | String; dir for other files. Use jla_va_covmatrix.dat |
colour_covmat_file | String; dir for other files. Use jla_vb_covmatrix.dat |
mag_stretch_covmat_file | String; dir for other files. Use jla_v0a_covmatrix.dat |
mag_colour_covmat_file | String; dir for other files. Use jla_v0b_covmatrix.dat |
stretch_colour_covmat_file | String; dir for other files. Use jla_vab_covmatrix.dat |
##Inputs
These parameters and data are inputs to the module, either supplied as parameters by the sampler or computed by some previous module. They are loaded from the data block.
Section | Parameter | Description |
---|---|---|
distances | z | Real vector; redshift sample values for theory |
mu | Real vector; theory distance modulus at sample redshifts | |
supernova_params | alpha | Real; SN shape parameter coefficient |
beta | Real; SN color parameter coefficient | |
M | Real; SN magnitude parameter baseline value; leave this fixed and vary deltaM. | |
deltaM | Real; SN magnitude parameter where M_actual = M + deltaM |
##Outputs
These parameters and data are computed as outputs from the module
Section | Parameter | Description |
---|---|---|
likelihoods | JLA_LIKE | Gaussian likelihood for this data set and theory mu(z) |
Updated