Utilizing Voronoi Tessellations to Determine Radial Density Profiles
Abstract
We have developed a novel method of determining 2D radial density profiles
for astronomical systems of discrete objects using Voronoi tessellations. This
Voronoi-based method was tested against the standard annulus-based method on 5
simulated systems of objects, following known Hubble density profiles of
varying parameters and sizes. It was found that the Voronoi-based method
returned radial density fits with lower uncertainties on the fitting parameters
across all 5 systems compared to the annulus-based method. The Voronoi-based
method also consistently returned more accurate estimates of the total number
of objects in each system than the annulus-based method, and this accuracy
increased with increasing system size. Finally, the Voronoi-based method was
applied to two observed globular cluster systems around brightest cluster
galaxies ESO 444-G046 and 2MASX J13272961-3123237 and the results were compared
to previous results for these galaxies obtained with the annulus-based method.
Again, it was found that the Voronoi-based method returned fits with lower
uncertainties on the fitting parameters, and the total number of globular
clusters returned are within errors of the annulus-based method estimates,
however also with lower uncertainties.