Presentation #115.10 in the session Multi-Messenger Astrophysics.
Gamma-ray bursts could serve as probes to the extreme physics which power them, yet the origin of their observed prompt emission and their jet structure is still shrouded in mystery. The Compton Spectrometer and Imager (COSI), designed to survey the gamma-ray sky at 0.2-5 MeV, could demystify the physics at play through its ability to localize and characterize GRBs as a Small Explorer satellite mission slated for launch in 2027. The detector array of COSI serves as a powerful wide-field spectrometer and polarimeter, and the surrounding active shields provide background rejection as well as allow for GRB triggering. This presentation will discuss COSI's contribution to multimessenger studies by its ability to localize GRBs with sub-degree positions and enable afterglow follow-ups. It will also delve into GRB characterization through maximum likelihood method analysis tools for joint spectral-polarization studies.