SMT

class hmf.mass_function.fitting_functions.SMT(*args, validate=True, **kwargs)[source]

Sheth-Mo-Tormen mass function fit.

For details on attributes, see documentation for FittingFunction.

Parameters:

  • nu2 (array_like) – A vector of peak-heights, \(\delta_c^2/\sigma^2\) corresponding to m

  • m (array_like, optional) – A vector of halo masses [units M_sun/h]. Only necessary if req_mass is True. Typically provides limits of applicability. Must correspond to nu2.

  • z (float, optional) – The redshift. Only required if req_z is True, in which case the default is 0.

  • n_eff (array_like, optional) – The effective spectral index at m. Only required if req_neff is True.

  • mass_definition (hmf.halos.mass_definitions.MassDefinition instance) – A halo mass definition. Only required for fits which explicitly include a parameterization for halo definition.

  • cosmo (astropy.cosmology.FLRW instance, optional) – A cosmology. Default is Planck15. Either omegam_z or cosmo is required if req_omz is True. If both are passed, omegam_z takes precedence.

  • **model_parameters (unpacked-dictionary) – These parameters are model-specific. For any model, list the available parameters (and their defaults) using <model>._defaults

Notes

The Sheth-Mo-Tormen [1] form is:

\[f_{\rm SMT}(\sigma) = A\sqrt{2a/\pi}\nu\exp(-a\nu^2/2)(1+(a\nu^2)^{-p})\]

References

[1]

Sheth, R. K., Mo, H. J., Tormen, G., May 2001. MNRAS 323 (1), 1-12. http://doi.wiley.com/10.1046/j.1365-8711.2001.04006.x

Attributes

Methods

__init__(*args, validate=True, **kwargs)[source]
classmethod get_measured_mdef()

Get the mass definition used in the defining simulation.

classmethod get_models() → dict[str, type]

Get a dictionary of all implemented models for this component.