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Clone wikicosmosis / default_modules / distances_2015
distances module
Output cosmological distance measures for dynamical dark energy
Name: distances
File: cosmosis-standard-library/background/dynamical_de_distances/distances.py
Version: 2015
Author(s):
- CosmoSIS team (code)
URL:
Cite:
- Linder, E.V. 2003. Phys. Rev. Lett. 90:091301
- Huterer, D., Turner, M.S. 2001. Phys. Rev. D64:123527
- Wetterich, C. 2004 Physics Letters B, Volume 594
Rules:
- None.
Assumptions:
Explanation
This small module was written for CosmoSIS. This module computes the angular diameter distance, luminosity distance,
and distance modulus for three different parametrisations of dark energy. w = w0 +(1-a)wa, w = w0+(ap-a)wa and and 2 parameter
EDE w(a) model from Wetterich 2004.
##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 |
|---|---|
| verbose | boolean, (default False) |
| w_model | int, = 0 for (w0,wa), =1 for (w0,wa,ap), =2 for EDE model (w0,ode_e)(default 0) |
| zmin | real, default=0.0; The minimum redshift at which to calculate the distance |
| zmax | real, default=0.0; The maximum redshift at which to calculate the distance |
| dz | real, default=0.01; The spacing between output redshift samples |
##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 |
|---|---|---|
| cosmological_parameters | h0 | real, hubble parameter H0/(100 km/s/Mpc) |
| omega_k | real, curvature density fraction today (default 0.0) | |
| omega_b | real, baryon density fraction today | |
| omega_c | real, cdm density fraction today | |
| w0 | real, w(z=0) equation of state of dark energy (default -1.0) | |
| wa | real, equation of state parameter w(a) = w_0 + w_a*(1-a) (default 0.0) | |
| ap | real, pivot scale factor w(a) = w_0 + w_a*(ap-a) | |
| ode_e | real, Early dark energy parameters |
##Outputs
These parameters and data are computed as outputs from the module
| Section | Parameter | Description |
|---|---|---|
| distances | nz | integer, number of z samples |
| z | 1D real array, redshifts of samples | |
| d_a | 1D real array, angular diameter distance in Mpc | |
| d_m | 1D real array, co-moving distance in Mpc | |
| d_l | 1D real array, luminosity distance in Mpc | |
| mu | 1D real array, distance modulus |
Updated