Götz, D.D.GötzBoulade, O.O.BouladeCordier, B.B.CordierLe Floc'h, E.E.Le Floc'hPinsard, F.F.PinsardAmiaux, J.J.AmiauxTourrette, T.T.TourretteBasa, S.S.BasaVergani, S.S.VerganiAtteia, J. L.J. L.AtteiaCOVINO, StefanoStefanoCOVINOGHIRLANDA, GiancarloGiancarloGHIRLANDATanvir, N.N.TanvirBlain, A.A.BlainO'Brien, P.P.O'BrienROSSI, AndreaAndreaROSSISTRATTA, MARIA GIULIANAMARIA GIULIANASTRATTACASELLA, PiergiorgioPiergiorgioCASELLABozzo, E.E.BozzoTenzer, C.C.TenzerOrleanski, P.P.OrleanskiAMATI, LORENZOLORENZOAMATI2020-10-092020-10-0920180037-8720http://hdl.handle.net/20.500.12386/27688The Infra-Red Telescope (IRT) on board THESEUS will play a key role in identifying and characterizing moderate to high redshift Gamma-Ray Bursts afterglows. The IRT enables the on board GRB autonomous redshift determination, thus allowing the ground based telescopes to be triggered on a redshift pre-selected sample and finally fulfilling the cosmological goals of the mission. The IRT will be composed by a primary mirror of 0.7 m of diameter coupled to a single camera in a Cassegrain design. It will work in the 0.7-1.8 mu m wavelength range, and will provide a 10×10 arc min imaging field of view with sub-arc second localization capabilities, and, at the same time, a 5×5 arc min field of view with moderate (R up to ∼500) spectroscopic capabilities. Its sensitivity, mainly limited by the satellite jitter, is adapted to detect all the GRBs, localized by the THESEUS SXI/XGIS instruments, and to acquire spectra for the majority of them.STAMPAenArticlehttp://sait.oat.ts.astro.it/MSAIt890218/index.html2018MmSAI..89..148GFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation::PE9_17 Instrumentation – telescopes, detectors and techniques