Photo credit: Arthur. Guilin, China, 2013

UniversalFit is a program that computes the fitting functions for the unevolved/evolved subhalo mass/velocity functions according to the universal model given in “Statistics of Dark Matter Substructure I” (Jiang & van den Bosch 2014).

Upon user input of

- host halo mass,

- cosmology,

- observation redshift,

UniversalFit outputs the best-fit parameters p1-p5 of the function

that best describes the average subhalo mass function or velocity function, where

for unevolved subhalo mass function (USMF),

for evolved subhalo mass function (ESMF),

for unevolved subhalo velocity function (USVF),

for evolved subhalo velocity function (ESVF).