Method
NumCosmoDistancesound_horizon
Declaration [src]
gdouble
nc_distance_sound_horizon (
NcDistance* dist,
NcHICosmo* cosmo,
const gdouble z
)
Description [src]
Compute the sound horizon $r_s$,
\begin{equation}
\theta_s (z) = \int_{z}^\infty \frac{c_s(z^\prime)}{E(z^\prime)} dz^\prime, \quad r_s (z) = \frac{\mathrm{sinn}\left(\sqrt{\Omega_{k0}}\theta_s\right)}{\sqrt{\Omega_{k0}}},
\end{equation}
where $c_s = \sqrt{c^{b\gamma 2}_s(z)}$ is the baryon-photon plasma speed of sound
(see nc_hicosmo_bgp_cs2() for more details)
and $E(z)$ is the normalized Hubble function [nc_hicosmo_E()].
Parameters
cosmo-
Type:
NcHICosmoA
NcHICosmo.The data is owned by the caller of the method. z-
Type:
const gdoubleRedshift $z$.