### halo mass function

(mass of distribution of dark matter)

A **halo mass function** is a distribution function
(essentially an unnormalized probability density function) mapping mass
to the quantity of dark matter halos with that mass.
It is of use in cosmology and cosmological simulations.

A **sub-halo mass function** is such a distribution of
sub-halos within a dark matter halo, and
a **conditional sub-halo mass function** is one parameterized
by the mass of the particular dark matter halo
(analogous to a conditional stellar mass function).

Note that the term **mass function** used here
is not in the sense of a probability mass function (PMF), a function yielding
the probability that some discrete random variable takes
on a given value.

(*cosmology,dark matter,function,mass*)
**Further reading:**

http://en.wikipedia.org/wiki/Halo_mass_function

https://ui.adsabs.harvard.edu/abs/2013MNRAS.434L..61M/abstract

Index