Origins of luminous UV emissions from the first galaxies at z = 15 - 10

The observed UV luminosity function at z ≧ 10 suggests the overabundance of UV-bright (M_UV < -20) and massive galaxies in comparison to pre-JWST theoretical predictions (e.g. Harikane+24, Donnan+24, Perez-Gonzalez+23). Several scenarios can explain the tension (e.g. Inayoshi+22, Dekel+23, Li+23, Mason+23, Yung+24, Shen+23), one of which is dust clearing by radiation-driven outflows (Ferrara+23, 24). To test this scenario, I estimate the extent to which radiation pressure is enhanced in dusty gas. I find that it is boosted by a factor of ~ 180(Z/0.1Zsun) compared to the standard Eddington limit (Figure 2). I show that a few galaxies observed at z > 10 have luminosities exceeding the effective Eddington luminosity for a dusty medium and are likely in the dusty outflow phase, while the other 80% of observed galaxies at z > 10 may have already experienced a dusty outflow and expelled their dust by the time of observation.