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BBN module
Simple prior on Omega_b h^2 from light element abundances
Name: BBN
File: cosmosis-standard-library/likelihood/bbn/bbn_ombh2.py
Version: PDG13
Author(s):
- B.D Fields
- P. Molaro
- S. Sarkar
URL: http://pdg.lbl.gov/2013/reviews/rpp2013-rev-bbang-nucleosynthesis.pdf
Cite:
- J. Beringer et al. (Particle Data Group), Phys. Rev. D86, 010001 (2012)
Rules:
- None.
Assumptions:
- Standard model of Big-Bang nucleosynthesis
Explanation
This small module was written for CosmoSIS.
Measurements of the abundances of light elements D, 3He, 4He, and 7Li
constrain the density budget at the epoch of nucleosynthesis in the first
three minutes after the big bang.
##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 |
|---|---|
| mean | float, replace the standard value measurement omega_b h^2 = 0.023 with a custom one (default 0.023) |
| sigma | float, replace the standard value error 0.002 with a custom one (default 0.002) |
##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 | omega_b | real, baryon density fraction today |
| h0 | real, hubble parameter H0/(100 km/s/Mpc) |
##Outputs
These parameters and data are computed as outputs from the module
| Section | Parameter | Description |
|---|---|---|
| likelihoods | BBN_LIKE | Gaussian likelihood value of supplied parameters |
Updated