SPECTRAL ENERGY DISTRIBUTION FITTING OF HETDEX PILOT SURVEY Lyα EMITTERS IN COSMOS AND GOODS-N

We use broadband photometry extending from the rest-frame UV to the near-IR to fit the individual spectral energy distributions of 63 bright (L(Lyα) > 1043 erg s−1) Lyα emitting galaxies (LAEs) in the redshift range 1.9 < z < 3.6. We find that these LAEs are quite heterogeneous, with stellar masses that span over three orders of magnitude, from 7.5 < log M/M☉ < 10.5. Moreover, although most LAEs have small amounts of extinction, some high-mass objects have stellar reddenings as large as E(B − V) ∼ 0.4. Interestingly, in dusty objects the optical depths for Lyα and the UV continuum are always similar, indicating that Lyα photons are not undergoing many scatters before escaping their galaxy. In contrast, the ratio of optical depths in low-reddening systems can vary widely, illustrating the diverse nature of the systems. Finally, we show that in the star-formation-rate–log-mass diagram, our LAEs fall above the “main-sequence” defined by z ∼ 3 continuum selected star-forming galaxies. In this respect, they are similar to submillimeter-selected galaxies, although most LAEs have much lower mass.

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