onepower.pk.Spectra.compute_A_term

Spectra.compute_A_term(mass, b_dm, dndlnm, mean_density0)

Integral over the missing haloes.

This term is used to compensate for low mass haloes that are missing from the integral in the matter 2-halo term. Equation A.5 of Mead and Verde 2021, 2011.08858

\(A(M_{\rm min}) = 1 - [1/\bar{\rho} \int_{M_{\rm min}}^{\infty} {\rm d}M M b(M) n(M)]\)

Here all missing mass is assumed to be in halos of minimum mass \(M_{\rm min} = {\rm min}(M)\)

This equation arises from

\(\int_{0}^{\infty} M b(M) n(M) {\rm d}M = \bar{\rho}\).

and

\(\int_{0}^{\infty} M n(M) dM = \bar{\rho}\).

This \(\bar{\rho}\) is the mean matter density at that redshift.