Emission Line Galaxies with the future ATLAS Probe: the spectroscopic follow-up to Roman

ATLAS (Astrophysics Telescope for Large Area Spectroscopy) Probe is a concept for a NASA probe-class space mission. It is the follow-up space mission to the Nancy Grace Roman Space Telescope, boosting its scientific return by obtaining deep IR slit spectroscopy for 70% of all galaxies imaged by a 2000 deg² Roman High Latitude Survey at z>0.5. ATLAS will measure accurate and precise redshifts for 200M galaxies out to z < 7+, and deliver spectra that enable a wide range of diagnostic studies of the physical properties of galaxies over most of cosmic history.

ATLAS Probe is a 1.5m telescope with a field of view of 0.4 deg², and uses Digital Micro-mirror Devices as slit selectors. It has a spectroscopic resolution of R = 1000 over 1-4 microns, and a spectroscopic multiplex factor of 6,000. ATLAS Probe will lead to transformative science over the entire range of astrophysics: from galaxy evolution to the dark Universe, from Solar System objects to the dusty regions of the Milky Way. In this talk, we will discuss the emission line galaxies expected from ATLAS Probe, and their implications for probing cosmic acceleration and galaxy evolution.

ATLAS Probe will provide wide field, highly multiplexed, densely sampled spectroscopy at high redshifts, producing a “time-lapse SDSS” spanning most of cosmic history. ATLAS will carry out three nested surveys (Wide/Medium/Deep): 2000 deg² to the line flux limit of 5×10^-18 erg/s/cm²; 100 deg² to AB ~ 25 (and the line flux limit of 1.2×10^-18 erg/s/cm²); 1 deg² to AB ~ 26 (and the line flux limit of 4.6×10^-19 erg/s/cm²). ATLAS Wide Survey will provide definitive measurements that can illuminate the nature of dark energy, and lead to revolutionary advances in particle physics and cosmology. ATLAS Medium and Deep surveys will enable a detailed study of how galaxy evolution depends on the cosmic web environment.