Hi,
I'm working on massive neutrinos and I would like to know the precise definition of the following items in params.ini :
- massless_neutrinos
- massive_neutrinos
- nu_mass_fractions
In particular, is massless_neutrinos equivalent to the effective number of neutrinos (N_eff or N_nu in most papers) ? Is it the case even if massive_neutrinos differs from 0?
I'd also like to know how I can obtain power spectra for different redshifts (e.g. from z=4 to z=0 with Delta_z=0.1).
Thanks a lot,
Frederic
CAMB : .ini definitions
-
- Posts: 4
- Joined: July 26 2007
- Affiliation: Institut d'Astrophysique de Paris
-
- Posts: 1943
- Joined: September 23 2004
- Affiliation: University of Sussex
- Contact:
Re: CAMB : .ini definitions
Yes, QED effects etc are usually accounted for by an effective number of massless_neutrinos (e.g. astro-ph/0111408). Since massive neutrinos are relativistic in the early universe anyway I usually always put the fractional number into the massless neutrinos, but I don't have an other justification for doing this (though I'm not sure the code would work with a fractional number of massive neutrinos).
Change transfer_redshift(x) to set the redshift for each transfer function/matter power spectrum.
Change transfer_redshift(x) to set the redshift for each transfer function/matter power spectrum.