The Gravitational-wave Ultraviolet Counterpart Imager (GUCI) network is a SmallSat mission concept designed to identify and characterize the early (dt < 1 d) UV emission from binary neutron star mergers. GUCI is comprised of 2 independently operating 12U cubesats in low-Earth orbits, each equipped with a wide-field ( 50 square degrees) UV imager. We will promptly uplink sky localizations of binary neutron star mergers from gravitational wave detectors to the spacecrafts. Unlike ground-based optical observatories that suffer from visibility (e.g., waiting for night to begin observing) and weather constraints, GUCI will begin imaging of gravitational wave localizations within one hour (on average). Each satellite will have a distinct bandpass, but will otherwise be identical. The multi-filter UV coverage and high cadence (95 minutes) will enable us to determine the origin of the early UV-bright emission from binary neutron star mergers - such observations cannot be accomplished from the ground, due to atmospheric transmission (bandpass) and visibility constraints (cadence).While not following up binary neutron star mergers, GUCI will conduct the first synoptic survey of the UV transient sky, imaging 1500 square degrees every 3 hours to a depth of 19.0 mag (AB). GUCI transient discoveries will address key Decadal Survey science questions such as how super-massive black holes accrete material and influence their surroundings, and which massive stars give rise to the different classes of core-collapse supernovae. It will naturally complement the Large Synoptic Survey Telescope and Square Kilometer Array in these time-domain studies. The key enabling technology for GUCI is the development of delta-doped CCD detectors, providing an order-of-magnitude improvement in throughput over the microchannel plates used for GALEX and the UVOT on Swift. Even with the modest aperture required by a cubesat form factor, GUCI will achieve sufficient sensitivity to detect binary neutron star mergers out to at least 100 Mpc. In this talk we describe the scientific objectives, instrument and mission implementation for the GUCI concept.
American Astronomical Society Meeting Abstracts #234
- Pub Date:
- June 2019