hmfast.halos.massfunc.T08HaloMassFunction
- class hmfast.halos.massfunc.T08HaloMassFunction[source]
Bases:
HaloMassFunctionHalo mass function from Tinker et al. (2008).
Calibrated for spherical-overdensity halo masses. In this implementation, the fitting coefficients are interpolated over the tabulated overdensity grid spanning \(\Delta_\mathrm{m} = 200\) to \(3200\).
Methods
dndlnm(cosmology, m, z[, mass_definition, ...])Compute the halo mass function \(dn/d\ln M\).
- dndlnm(cosmology, m, z, mass_definition=<hmfast.halos.massdef.MassDefinition object>, convert_masses=False)[source]
Compute the halo mass function \(dn/d\ln M\).
The halo mass function gives the comoving number density of halos per logarithmic mass interval:
\[\frac{dn}{d\ln M} = f(\sigma) \frac{\rho_{m,0}}{M} \left| \frac{d\ln \sigma^{-1}}{d\ln M} \right|\]In this model,
\[f(\sigma) = 0.5 A \left[\left(\frac{\sigma}{b}\right)^{-a} + 1\right] \exp\left(-\frac{c}{\sigma^2}\right),\]where \(f(\sigma)\) is the Tinker et al. (2008) fitting function, calibrated over a tabulated overdensity grid spanning \(\Delta_\mathrm{m} = 200\) to \(3200\), \(A\), \(a\), \(b\), and \(c\) are redshift-dependent fitting parameters, and \(\sigma(M)\) is the variance of the density field smoothed on the mass scale \(M\).
- Parameters:
- cosmologyCosmology
Cosmology used to evaluate the halo mass function.
- marray-like
Halo mass grid in physical \(M_\odot\).
- zarray-like
Redshift grid.
- mass_definitionMassDefinition, optional
Halo mass definition at which to evaluate the halo mass function. Defaults to the native \(200\mathrm{m}\) calibration definition.
- convert_massesbool, optional
Mass conversions are applied if
convert_massesis set toTrue.
- Returns:
- dndlnMfloat or array-like
Halo mass function values \(dn/d\ln M\) in comoving \(\mathrm{Mpc}^{-3}\), with shape \((N_m, N_z)\), where singleton dimensions get squeezed before return.