Spectral Energy Distribution Fitting of HETDEX Pilot Survey Lyman-alpha Emitters in COSMOS and GOODS-N

Alex Hagen; Robin Ciardullo; Caryl Gronwall; Viviana Acquaviva; Joanna Bridge; Gregory R. Zeimann; Guillermo A. Blanc; Nicholas A. Bond; Steven L. Finkelstein; Mimi Song; Eric Gawiser; Derek B. Fox; Henry Gebhardt; A. I. Malz; Donald P. Schneider; Niv Drory; Karl Gebhardt; Gary J. Hill

doi:10.1088/0004-637x/786/1/59

arXiv · 1403.4935

Spectral Energy Distribution Fitting of HETDEX Pilot Survey Lyman-alpha Emitters in COSMOS and GOODS-N

Alex Hagen·Robin Ciardullo·Caryl Gronwall·Viviana Acquaviva·Joanna Bridge·Gregory R. Zeimann·Guillermo A. Blanc·Nicholas A. Bond·Steven L. Finkelstein·Mimi Song·Eric Gawiser·Derek B. Fox·Henry Gebhardt·A. I. Malz·Donald P. Schneider·Niv Drory·Karl Gebhardt·Gary J. Hill

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Abstract

We use broadband photometry extending from the rest-frame UV to the near-IR to fit the individual spectral energy distributions (SEDs) of 63 bright (L(Ly-alpha) > 10^43 ergs/s) Ly-alpha 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 < 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 Ly-alpha and the UV continuum are always similar, indicating that Ly-alpha 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 (SFR)-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 sub-mm-selected galaxies, although most LAEs have much lower mass.

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Alex Hagen, Robin Ciardullo, Caryl Gronwall, Viviana Acquaviva, Joanna Bridge, Gregory R. Zeimann, Guillermo A. Blanc, Nicholas A. Bond, Steven L. Finkelstein, Mimi Song, Eric Gawiser, Derek B. Fox, Henry Gebhardt, A. I. Malz, Donald P. Schneider, Niv Drory, Karl Gebhardt, Gary J. Hill. 2014-03-19. Spectral Energy Distribution Fitting of HETDEX Pilot Survey Lyman-alpha Emitters in COSMOS and GOODS-N. https://doi.org/10.1088/0004-637x/786/1/59

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