0 Assigned ID: 3481 ----- Attempting Submission 1 (Fri Mar 25 20:01:17 GMT 2022) ----- HST Phase I Proposal 3481 successfully submitted. Receipt: # 3481-1 ----- Attempting Submission 2 (Fri Mar 25 20:11:09 GMT 2022) ----- Over the past 15 years, 365 orbits of deep, far-UV (1600 A) imaging have been obtained in 151 pointings with the ACS Solar Blind Channel (SBC) in the GOODS and COSMOS legacy extragalactic fields. The images cover ~45 sq. arcmin. to FUV=28-29.8 (AB, 3 sigma, 0.5" radius, exposure times vary) and provide high resolution far-UV imaging of galaxies at z<0.75. Reduced images have been made public for only 21% of orbits (78/365) and 26% of pointings (39/151). Legacy archival HST programs have been awarded to compile all near-UV, optical, and near-IR HST imaging in these fields. We propose to complete the HST legacy by reducing all SBC far-UV images in these fields, map them to existing archival images, and provide images & catalogs. We expect ~1000 detected galaxies at 0.2<z<0.9. The data products will enable many studies including Lyman Continuum escape at z~1.2-1.5, resolved dust maps, bursty star formation, and star-forming clump sizes. We will measure far-UV number counts down to AB=29.8 in three independent fields, with 2.8x the area of previous counts, decreasing total uncertainty in the UV extragalactic background light (EBL) by a factor of ~3 (from ~21% to ~7%), bringing it better in line with estimates from funded archival programs to determine the EBL at all other HST wavelengths. This will help inform a current tension between direct EBL measurements (via New Horizons) and those from integrated counts. With photo-zs, we will also model the evolution of the UV EBL. This will be the definitive result for the foreseeable future and will strongly constrain various aspects of galaxy evolution and acurately correct for gamma-ray attenuation of NASA Fermi sources. Prof. Brian Siana, Dr. Harry Teplitz, Dr. James Colbert, and Dr. Anahita Alavi all have extensive experience working with ACS/SBC datasets, providing legacy UV data products to the MAST archive (HDF, UVUDF). Dr. Alberto Dominguez, Prof. Marco Ajello, Prof. Joel Primack, and Mr. Alberto Saldana-Lopez are experts in modeling the extragalactic background light, its evolution, and the attenuation of gamma rays from distant objects. Prof. Simon Driver is an expert in measuring extragalactic backgrounds at all wavelengths and modeling the energy output of galaxies at all redshifts. Galaxies 0 Legacy false false true false false false SUPPORTED