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cosmosis / default_modules / WiggleZBao_1401.0358v2

WiggleZBao module

Compute the likelihood of the supplied expansion history against WiggleZ BAO data

Name: WiggleZBao

File: cosmosis-standard-library/likelihood/wigglez_bao/wigglez_bao.py

Version: 1401.0358v2

Author(s):

  • WiggleZ Team
  • MontePython Team

URL: http://www.smp.uq.edu.au/wigglez-data/

Cite:

  • MNRAS 441, 3524 (2014)

Rules:

Assumptions:

  • WiggleZ dark energy survey data set
  • FLRW metric and standard BAO size

Explanation

This module gives a likelihood of the redshift-distance and redshift-Hubble
relations in combined form D_v = (da2 * (1+z)2 * dr)**(1./3.)
where dr = z / H. It uses the sound horizon at last-scatter rs_zdrag and
the predicted expansion since last scattering to predict the BAO size
at the redshifts at which the WiggleZ survey measured them.

A correlated Gaussian likelihood is then returned.

##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_file string, path to file with measured z - D_v values in (default: included file)
weight_file string, path to inverse covariance matrix file (default: included file)
rs_fiducial Real, Fiducial value of sound horizon at last scattering used in making data (default=148.6)
verbose Bool, Print extra output (default = False)

##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 1D real array, redshifts of samples
d_a 1D real array, angular diameter distance in Mpc
h 1D real array, hubble parameter with in units of Mpc
rz_zdrag real, sound horizon at last scattering in Mpc

##Outputs

These parameters and data are computed as outputs from the module

Section Parameter Description
likelihoods wigglez_bao_like real, likelihood of supplied expansion history

Updated