Dark matter annihilation signals coming from Galactic subhaloes may account
for a small fraction of unassociated point sources detected in the Second
Fermi-LAT catalogue (2FGL). To investigate this possibility, we present Sibyl,
a Random Forest classifier that offers predictions on class memberships for
unassociated Fermi-LAT sources at high Galactic latitudes using gamma-ray
features extracted from the 2FGL. Sibyl generates a large ensemble of
classification trees that are trained to vote on whether a particular object is
an active galactic nucleus (AGN) or a pulsar. After training on a list of 908
identified/associated 2FGL sources, Sibyl reaches individual accuracy rates of
up to 97.7% for AGNs and 96.5% for pulsars. Predictions for the 269
unassociated 2FGL sources at |b| > 10 degrees suggest that 216 are potential
AGNs and 16 are potential pulsars (with majority votes greater than 70%). The
remaining 37 objects are inconclusive, but none is an extreme outlier. These
results could guide future quests for dark matter Galactic subhaloes.Comment: 5 pages, 3 figures, 2 tables, accepted for publication in MNRAS.
Complete tables can be retrieved at http://www.gae.ucm.es/~mirabal/sibyl.htm