LFKit logo Luminosity function models#

This section introduces the luminosity function models exposed by lfkit.LuminosityFunction. These models describe the abundance of galaxies as a function of magnitude, usually written as \(\Phi(M)\).

The examples focus on constructing, evaluating, visualizing, and comparing luminosity function models. Magnitude integrals, completeness calculations, apparent magnitude limits, redshift-density weighting, and conditional luminosity functions are covered on separate pages.

The API is centered on lfkit.LuminosityFunction. A luminosity function object stores the chosen model and evaluates it through lfkit.LuminosityFunction.phi().

The number-density units follow the normalization supplied to the luminosity function. For example, if phi_star is supplied in \({\rm Mpc}^{-3}\,{\rm mag}^{-1}\), then \(\Phi(M)\) has units of \({\rm Mpc}^{-3}\,{\rm mag}^{-1}\).