  Here we present Halo-FDCA, a robust open source Python package for modeling
and estimating total flux densities of radio (mini) halos in galaxy clusters.
Radio halos are extended ( ~200 - 1500 kpc in size) synchrotron emitting
sources found in galaxy clusters that trace the presence of cosmic rays and
magnetic fields in the intracluster medium (ICM). These sources are centrally
located and have a low surface brightness. Their exact origin is still unknown
but they are likely related to cosmic rays being re-accelerated in-situ by
merger or sloshing driven ICM turbulence. The presented algorithm combines the
numerical power of the Markov Chain Monte Carlo routine and multiple
theoretical models to estimate the total radio flux density of a radio halo
from a radio image and its associated uncertainty. This method introduces a
flexible analytic fitting procedure to replace existing simplistic manual
measurements prone to biases and inaccuracies. It allows to easily determine
the properties of the emission and is particularly suitable for future studies
of large samples of clusters.
