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arXiv · 2301.00017

Broad emission lines in optical spectra of hot dust-obscured galaxies can contribute significantly to JWST/NIRCam photometry

Jed McKinney·Luke Finnerty·Caitlin Casey·Maximilien Franco·Arianna Long·Seiji Fujimoto·Jorge Zavala·Olivia Cooper·Hollis Akins·Alexandra Pope·Lee Armus·B. T. Soifer·Kirsten Larson·Keith Matthews·Jason Melbourne·Michael Cushing
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Abstract

Selecting the first galaxies at z>7-10 from JWST surveys is complicated by z<6 contaminants with degenerate photometry. For example, strong optical nebular emission lines at z<6 may mimic JWST/NIRCam photometry of z>7-10 Lyman Break Galaxies (LBGs). Dust-obscured 3 -1.5$ and z>4. While there are some redshifts (z~3.75) where our stack is more degenerate with the photometry of z>10 LBGs between $\lambda_{rest}\sim0.3-0.8\,\mu$m, redder filter coverage beyond $\lambda_{obs}>3.5\,\mu$m and far-IR/sub-mm follow-up may be useful for breaking the degeneracy and making a crucial separation between two fairly unconstrained populations, dust-obscured galaxies at z~3-6 and LBGs at z>10.

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Jed McKinney, Luke Finnerty, Caitlin Casey, Maximilien Franco, Arianna Long, Seiji Fujimoto, Jorge Zavala, Olivia Cooper, Hollis Akins, Alexandra Pope, Lee Armus, B. T. Soifer, Kirsten Larson, Keith Matthews, Jason Melbourne, Michael Cushing. 2022-12-30. Broad emission lines in optical spectra of hot dust-obscured galaxies can contribute significantly to JWST/NIRCam photometry. https://doi.org/10.3847/2041-8213%2Facc322

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