In the computation of the bispectrum by camb, there is a factor 3/5 multiplied to dr such that
term = r^2 * TimeStepsNongauss%dpoints(i) * (3./5)
did not figure out the origin of the factor. Is there any reason for the factor?
Bispectrum computation by camb
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Jaiseung Kim
- Posts: 13
- Joined: January 21 2008
- Affiliation: Max Planck Institute for Astrophysics
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Antony Lewis
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- Joined: September 23 2004
- Affiliation: University of Sussex
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Re: Bispectrum computation by camb
It's just the conventional definition of f_NL (in terms of matter dominated superhorizon potentials) which has a 3/5 factor compared to the natural definition in terms of curvature perturbations.