The dark matter halo of the Milky Way is expected to contain an abundance of smaller subhalos .
These subhalos can be dense and produce potentially observable fluxes of gamma rays .
In this paper , we search for dark matter subhalo candidates among the sources in the Fermi-LAT Second Source Catalog which are not currently identified or associated with counterparts at other wavelengths .
Of the nine high-significance , high-latitude ( |b| > 60 ^ { \circ } ) , non-variable , unidentified sources contained in this catalog , only one or two are compatible with the spectrum of a dark matter particle heavier than approximately 50 – 100 GeV .
The majority of these nine sources , however , feature a spectrum that is compatible with that predicted from a lighter ( \sim 5-40 GeV ) dark matter particle .
This population is consistent with the number of observable subhalos predicted for a dark matter candidate in this mass range and with an annihilation cross section of a simple thermal relic ( \sigma v \sim 3 \times 10 ^ { -26 } cm ^ { 3 } /s ) .
Observations in the direction of these sources at other wavelengths will be necessary to either reveal their astrophysical nature ( as blazars or other active galactic nuclei , for example ) , or to further support the possibility that they are dark matter subhalos by failing to detect any non-gamma ray counterpart .