Speaker
Description
Following the design phase and laboratory testing of the prototype, the development of the ASTRI Stellar Intensity Interferometry Instrument (SI3) entered the crucial hardware integration phase at the end of 2025. The process of integrating this system into the array involves rigorous testing of all electronic and optical components, with particular attention to the critical challenge of optimizing light injection into the multimode optical fiber bundle. This presentation details the activities carried out in the first half of 2026. We will briefly describe the laboratory assembly of the first three Focal Plane Modules (FPMs) and Optical Modules (OMs), followed by the on-site installation of the assembled instruments on the ASTRI 5, 6 and 7 telescopes at the Teide Observatory (Tenerife, Spain). Furthermore, we will present the preliminary results from the initial on-sky testing phase conducted during the summer. This includes actual measurements of the Point Spread Function (PSF), in-situ verification of light injection efficiency, and the first scientific validation run on a sample of bright stars.
