Definitive Answers on Environmental Pre-processing in Cosmic Noon Protoclusters
| Program ID | 19044 |
|---|---|
| Science Category | Large Scale Structure of the Universe |
| Program Type | Analysis |
| Category | Medium |
| Principal Investigator | Jaclyn Champagne |
| PI Institution | Space Telescope Science Institute / STScI |
| Co-Investigators |
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| Abstract | Galaxy protoclusters, the progenitors of today's massive galaxy clusters, host dense sites of active star- and supermassive black hole formation at cosmic noon and beyond (z>2). However, connecting protocluster evolution from primordial overdensities to virialized clusters has been observationally elusive. When do protocluster galaxies experience the bulk of their stellar mass and supermassive black hole assembly compared to the field? What is the role of the local environment versus global properties like halo mass in accelerating star formation and/or permanent quenching? Because protoclusters are both extremely rare on the sky and spatially extended on 10s-arcmin scales, typical extragalactic surveys from the ground and space have been limited in their ability to amass statistically large protocluster samples. Further, heterogeneous selection techniques and incomplete spectroscopic followup hinder a complete census of their member galaxies. The Deep HLWAS will enable the immediate spectroscopic confirmation of star-forming and quiescent galaxies across 20 sq. deg., which will enable us to identify at least 1000 protoclusters at 1<z<3. Here, we will develop pipeline tools for automated image/spectral extraction, photometric and spectroscopic redshift fitting, and SED fitting for emission line galaxies at cosmic noon, which we will use to identify overdensities through state-of-the-art linking methods. We will investigate the role of environment in accelerating or halting star formation by (1) identifying overdensities and sorting them by virial halo mass, (2) classifying overdensity members as star-forming, quiescent, and/or AGN through nebular line indicators, and (3) placing the star-forming properties of overdensity galaxies in the context of local overdensity and clustercentric phase space. We will publicly release our pipeline tools and overdensity catalog which will enable a complete revolution of our understanding of large scale structure collapse. |