*3.2. On-Board Scientific Instruments*

Based on the above mentioned mission scientific requirements and the unique heritage and worldwide leadership of the Consortium in the enabling technologies, the THESEUS payload (Figure 1) will include the following scientific instruments:


• InfraRed Telescope (IRT, 0.7–1.8 µm): a 0.7-m class IR telescope with 15' × 15' FoV, with imaging (I, Z, Y, J and H) and moderate spectroscopic (resolving power, R 400, through 2' × 2' grism) capabilities [33].

The instruments' Data Handling Units (DHU) will operate in synergy, thus optimizing the capability of detecting, identifying and localizing likely transients in the SXI, XGIS and IRT FoVs, as well as providing the unprecedented capability of on-board autonomous redshift measurements.
