The Gamow Explorer: A High Redshift Universe Gamma-Ray Burst Mission

Gamma-Ray Bursts (GRBs) can be used to address high priority scientific questions on the formation of the Universe including: When did star formation begin and how did it evolve? When and how did the intergalactic medium become re-ionized? What processes governed its early chemical enrichment? Long GRBs signal when a massive star explodes as a supernova and, as such, they can provide an independent tracer of star formation. The GRB afterglow is a bright beacon lasting a few days that can be used out to the highest redshifts to both probe the intervening material from the host galaxy and intergalactic medium, and also trace star formation and its evolution.

The Gamow Explorer will utilize a wide field of view X-ray telescope to detect and locate GRBs with arc minute precision and a sensitivity ten times Swift to identify z > 6 GRBs. A rapidly slewing spacecraft points an Infrared telescope to obtain an arc second location and use the Lyman alpha dropout to determine which GRBs have a redshift greater than 6. An alert to the ground will enable follow-up by large telescopes for z > 6 GRBs. The Gamow Explorer will be proposed to the 2021 NASA MIDEX opportunity, for launch in 2028. It will be a key component in the multi-messenger era of JWST, 30-m class telescopes and next generation gravitational wave detectors.