SOVirial¶

class hmf.halos.mass_definitions.SOVirial(**model_params)[source]¶

A mass definition based on spherical overdensity.

Density threshold isgiven by Bryan and Norman (1998).

Attributes

`colossus_name`	The name of the mass definition in Colossus format, if applicable.
`references`	References to cite when this model is used, each a formatted citation string.

Methods

change_definition(m: ndarray, mdef, profile=None, c=None, z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))¶

Change the spherical overdensity mass definition.

This requires using a profile, for which the halomod package must be used.

Parameters:

m (float or array_like) – The halo mass to be changed, in \(M_\odot/h\). Must be broadcastable with c, if provided.
mdef (MassDefinition subclass instance) – The mass definition to which to change.
profile (halomod.profiles.Profile instance, optional) – An instantiated profile object from which to calculate the expected definition change. If not provided, a mocked NFW profile is used.
c (float or array_like, optional) – The concentration(s) of the halos given. If not given, the concentrations will be automatically calculated using the profile object.

Returns:

m_f (float or array_like) – The masses of the halos in the new definition.
r_f (float or array_like) – The radii of the halos in the new definition.
c_f (float or array_like) – The concentrations of the halos in the new definition.

static critical_density(z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))¶: Get the critical density of the Universe at redshift z, [h^2 Msun/Mpc^3].

classmethod get_models() → Mapping[str, type]¶

Get a read-only mapping of all implemented models for this component.

The mapping is a live view of the registry, so it shows models registered later, but it can not be used to add or remove models.

halo_density(z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))[source]¶: The density of haloes under this definition.

halo_overdensity_crit(z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))¶: Compute the halo overdensity with respect to the critical density.

halo_overdensity_mean(z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))¶: Compute the halo overdensity with respect to the mean density.

m_to_r(m, z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))¶

Return the radius corresponding to m for this mass definition.

Parameters:: m (float or array_like) – The mass to convert to radius. Should be in the same units (modulo volume) as halo_density().

Notes

Computed as \(\left(\frac{3m}{4\pi \rho_{\rm halo}\right)\).

classmethod mean_density(z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))¶: Get the mean density of the Universe at redshift z, [h^2 Msun / Mpc^3].

r_to_m(r, z=0, cosmo=FlatLambdaCDM(name='Planck18', H0=<Quantity 67.66 km / (Mpc s)>, Om0=0.30966, Tcmb0=<Quantity 2.7255 K>, Neff=3.046, m_nu=<Quantity [0., 0., 0.06] eV>, Ob0=0.04897))¶

Return the mass corresponding to r for this mass definition.

Parameters:: r (float or array_like) – The radius to convert to mass. Units should be compatible with halo_density().

Notes

Computed as \(\frac{4\pi r^3}{3} \rho_{\rm halo}\).