THESEUS is a mission concept designed to survey transient events in the high-energies (0.3 -- 10 MeV) across the whole sky and over the time scale of cosmic history.
The mission aims to complete a panorama and census of gamma-ray bursts (GRBs) from the Universe's first billion years, and reconcile the life cycle of the first stars.
THESEUS is expected to work on real-time triggers and following accurate locations of the sources, which may be used by other space- or ground-based telescopes operating at X-ray, Gamma-ray and other complementary wavelengths.
The space observatory would study gamma-ray bursts (GRBs) and transient phenomena relating to X-ray and Gamma-ray sources (e.g., compact X-ray binaries) and their association with supernova and nova including events like shock break-outs, black hole tidal disruption events, and magnetar flares. Compact X-ray binary sciences involve phenomena that deserves alerts and follow-ups where THESEUS will be fundamental. THESEUS is suitable to study accretion physics, accretion disks, outburst cycles, variability properties of compact X-ray binaries on different timescales for different classes of these systems. New sources and new states of sources will be recovered and the accumulated data over the years will be essential in explaining theoretical and observational controversies and complexities along with yielding new physics and theories.