Stellar halos offer fossil evidence for hierarchical structure formation .
Since halo assembly is predicted to be scale-free , stellar halos around low-mass galaxies constrain properties such as star formation in the accreted subhalos and the formation of dwarf galaxies .
However , few observational searches for stellar halos in dwarfs exist .
Here we present gi photometry of resolved stars in isolated Local Group dwarf irregular galaxy IC 1613 ( M _ { \star } \sim 10 ^ { 8 } M _ { \odot } ) .
These Subaru/Hyper Suprime-Cam observations are the widest and deepest of IC 1613 to date .
We measure surface density profiles of young main-sequence , intermediate to old red giant branch , and ancient horizontal branch stars outside of 12 \arcmin ( \sim 2.6 kpc ; 2.5 half-light radii ) from the IC 1613 center .
All of the populations extend to \sim 24 \arcmin ( \sim 5.2 kpc ; 5 half-light radii ) , with the older populations best fit by a broken exponential in these outer regions .
Comparison with earlier studies sensitive to IC 1613 ’ s inner regions shows that the density of old stellar populations steepens substantially with distance from the center ; we trace the g -band effective surface brightness to an extremely faint limit of \sim 33.7 mag arcsec ^ { -2 } .
Conversely , the distribution of younger stars follows a single , shallow exponential profile in the outer regions , demonstrating different formation channels for the younger and older components of IC 1613 .
The outermost , intermediate-age and old stars have properties consistent with those expected for accreted stellar halos , though future observational and theoretical work is needed to definitively distinguish this scenario from other possibilities .