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The distribution and properties of the first galaxies and quasars arecritical pieces of the puzzle in understanding galaxy evolution and cosmicreionization. Previous studies have often excluded unresolved sources aspotential low redshift interlopers. We combine broadband color and photometricredshift analysis with morphological selections to identify a robust sample ofcandidates consistent with unresolved point sources at redshift $z\sim8$ usingdeep Hubble Space Telescope images. We also examine G141 grism spectroscopicdata to identify and eliminate dwarf star contaminants. From these analyses, weidentify three, bright ($M_{UV}\lesssim-22$ ABmag) dropout point sources at$7.5<z<8.1$. Spectral energy distribution analyses suggest that these sourcesare either quasars or compact star-forming galaxies. The flux captured by theIRAC 4.5 $\mu$m channel suggests that they have moderate $H\beta$+$[OIII]$equivalent widths. We calculate the number density of point sources at$z\sim7$-8, and find that a double powerlaw model well describes the pointsource distribution. We then extend our analysis to estimate the combined pointsource + galaxy luminosity function and find that the point sources have anon-negligible contribution to the bright-end excess. The fact that the pointsources dominate only at $M_{UV}\lesssim-22$ suggests that their contributionto cosmic reionization is likely limited. While spectroscopic follow-up isneeded to confirm the nature of these point sources, this work demonstratesthat the inclusion of Lyman dropout point sources is necessary for a completecensus of the early galaxies at the epoch of cosmic reionization.

Unresolved z~8 point sources and their impact on the bright end of the galaxy luminosity function