halo_mass_to_virial_velocity¶
- halotools.empirical_models.halo_mass_to_virial_velocity(total_mass, cosmology, redshift, mdef)[source]¶
The circular velocity evaluated at the halo boundary, \(V_{\rm vir} \equiv \sqrt{GM_{\rm halo}/R_{\rm halo}}\).
- Parameters:
- total_massarray_like
Total mass of the halo; can be a scalar or numpy array.
- cosmologyobject
Instance of an Astropy
cosmologyobject.- redshift: array_like
Can either be a scalar, or a numpy array of the same dimension as the input
mass.- mdef: str
String specifying the halo mass definition, e.g., ‘vir’ or ‘200m’.
- Returns:
- vvirarray_like
Virial velocity in km/s.
Notes
See Spatial Profiles of Halos for derivations and implementation details.