clenspy.protocols.Profile

class clenspy.protocols.Profile(*args, **kwargs)

Bases: Protocol

A spherically symmetric halo profile and its projections.

The halo is fixed in the constructor; the radius is an argument to the method. Every method is vectorised over its radius argument.

Satisfied by clenspy.halo.NfwProfile and clenspy.halo.EinastoProfile. The four projections are related by

\[\bar\Sigma(<R) = \frac{2}{R^2}\int_0^R \Sigma(R')R'\,dR', \qquad \Delta\Sigma(R) = \bar\Sigma(<R) - \Sigma(R),\]

but each is declared separately because each has a closed form worth evaluating directly – forming one from the others cancels badly at small \(R/r_s\) (see NfwProfile._gbarNfw).

NOTE: convergence and shear are deliberately not in this contract. They need \(\Sigma_{\rm crit}\), which is a property of the lens-source geometry rather than of the halo, so they belong to the lensing layer. EinastoProfile carries them with a sigma_crit=1.0 default; that is a historical anomaly, not the contract.

__init__(*args, **kwargs)

Methods

__init__(*args, **kwargs)
deltasigma(R)	Excess surface density \(\Delta\Sigma(R)\) [Msun/Mpc^2].
density(r)	3D density \(\rho(r)\) [Msun/Mpc^3].
fourier(k)	Fourier transform of \(\rho\), \(u(k)\) [dimensionless].
mean_sigma(R)	Mean interior surface density \(\bar\Sigma(<R)\) [Msun/Mpc^2].
sigma(R)	Projected surface density \(\Sigma(R)\) [Msun/Mpc^2].

density(r)

3D density \(\rho(r)\) [Msun/Mpc^3].

sigma(R)

Projected surface density \(\Sigma(R)\) [Msun/Mpc^2].

mean_sigma(R)

Mean interior surface density \(\bar\Sigma(<R)\) [Msun/Mpc^2].

deltasigma(R)

Excess surface density \(\Delta\Sigma(R)\) [Msun/Mpc^2].

fourier(k)

Fourier transform of \(\rho\), \(u(k)\) [dimensionless].