0 Assigned ID: 1054 ----- Attempting Submission 1 (Fri Apr 10 23:38:06 GMT 2015) ----- Over 40 bright quasars powered by supermassive black holes (SMBHs) with estimated masses greater than a billion solar masses have been discovered at redshifts greater than 6. To explain the rapid assembly of these SMBHs, massive seed black holes and/or (super-)Eddington accretion are required. In recent work, we have shown that a galaxy forming around a massive seed black hole has different stellar properties than typical first-generation galaxies, caused by X-ray radiative feedback from the central black hole. We propose to construct observational diagnostics from our radiation hydrodynamics simulations to test different black hole seeding scenarios. The primary goal of this proposal is to compute the following synthetic observables for these galaxies: (1) spectral energy distributions and associated imaging and photometry, (2) emission line profiles and strengths in the rest-frame UV and optical, (3) evolution tracks in color-color diagrams and emission line measures, and (4) rest-frame IR/sub-mm predictions. These products will provide guidance when searching for galaxies that initially hosted a massive black hole seed in the Hubble Extreme Deep Field, Frontier Fields, and future JWST observations, placing further constraints on the origins of the z = 6 quasars. We will make all of the analysis tools and data products publicly available. COSMOLOGY 0 Regular false false false false true SUPPORTED