I am sorry if this is a trivial question, but I am new to CAMB and I am trying to figure out the transfer function output file.
One output file generated is the output_root_transfer.dat, which contains transfer functions for various quantities.
The CAMB readme says that the columns contain:
k/h , \Delta / k^2 and so on...
My query is, how do I get the power spectrum from these values?
If the second column has \Delta/k^2, I thought multiplying by k^2 would get me \Delta, and then squaring it would give me the dimensionless power spectrum, from which I can get the power spectrum:
P(k) = 2\pi^2 \Delta^2 / k^3
However, this does not seem to generate the well-known shape of the power spectrum.
Any help on what exactly the output file contains would help me a great deal.
CAMB - Help with Transfer Function Outputs
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Re: CAMB - Help with Transfer Function Outputs
The docs are correct. The CAMB notes give some relations between different power spectra definitions:
http://cosmologist.info/notes/CAMB.pdf
http://cosmologist.info/notes/CAMB.pdf