# TrivialProfile¶

class halotools.empirical_models.TrivialProfile(cosmology=FlatLambdaCDM(name="WMAP5", H0=70.2 km / (Mpc s), Om0=0.277, Tcmb0=2.725 K, Neff=3.04, m_nu=[ 0. 0. 0.] eV, Ob0=0.0459), redshift=0.0, mdef='vir', **kwargs)[source] [edit on github]

Profile of dark matter halos with all their mass concentrated at exactly the halo center.

Parameters: cosmology : object, optional Astropy cosmology object. Default is set in sim_defaults. redshift : float, optional Default is set in sim_defaults. mdef: str, optional String specifying the halo mass definition, e.g., ‘vir’ or ‘200m’. Default is set in model_defaults.

Examples

You can load a trivial profile model with the default settings simply by calling the class constructor with no arguments:

>>> trivial_halo_prof_model = TrivialProfile()


Methods Summary

 dimensionless_mass_density(scaled_radius, …) Physical density of the halo scaled by the density threshold of the mass definition. enclosed_mass(radius, total_mass) The mass enclosed within the input radius, $$M( Methods Documentation dimensionless_mass_density(scaled_radius, total_mass)[source] [edit on github] Physical density of the halo scaled by the density threshold of the mass definition. The dimensionless_mass_density is defined as \(\tilde{\rho}_{\rm prof}(\tilde{r}) \equiv \rho_{\rm prof}(\tilde{r}) / \rho_{\rm thresh}$$, where $$\tilde{r}\equiv r/R_{\Delta}$$.

Parameters: scaled_radius : array_like Halo-centric distance r scaled by the halo boundary $$R_{\Delta}$$, so that $$0 <= \tilde{r} \equiv r/R_{\Delta} <= 1$$. Can be a scalar or numpy array. total_mass: array_like Total halo mass in $$M_{\odot}/h$$; can be a number or a numpy array. dimensionless_density: array_like Dimensionless density of a dark matter halo at the input scaled_radius, normalized by the density_threshold $$\rho_{\rm thresh}$$ for the halo mass definition, cosmology, and redshift. Result is an array of the dimension as the input scaled_radius.
enclosed_mass(radius, total_mass)[source] [edit on github]

The mass enclosed within the input radius, $$M(<r) = 4\pi\int_{0}^{r}dr'r'^{2}\rho(r)$$.

For the TrivialProfile, this is equal to the total mass of the halo for all non-zero radii.

Parameters: radius : array_like Halo-centric distance in Mpc/h units; can be a scalar or numpy array total_mass : array_like Total mass of the halo; can be a scalar or numpy array of the same dimension as the input radius. enclosed_mass: array_like The mass enclosed within radius r, in $$M_{\odot}/h$$; has the same dimensions as the input radius.