New results from test-beam performance studies of 3D triplet modules for the ATLAS ITk detector

Le résumé fourni par la source

For the High Luminosity upgrade of the Large Hadron Collider (HL-LHC), the ATLAS 1 Inner Detector will be replaced by the all-silicon Inner Tracker (ITk), designed to operate in a significantly more challenging radiation environment and at higher collision rates. The ITk Pixel Detector will employ both planar and 3D silicon sensor technologies, with the latter selected for the innermost layer due to its superior radiation hardness. The 3D pixel sensors, produced by FBK (Italy) and SINTEF (Norway), are assembled into triplet modules, where three single bare modules are interconnected via a flex circuit. This configuration represents the final detector layout and thus a substantial step from previous R&D studies performed on single-chip assemblies. This work focuses on the experimental characterisation of triplet modules in beam-test conditions. Modules equipped with both the preproduction readout chip ITkPixV1.1 and the production ITkPixV2 were assembled and tested in laboratory setups, irradiated at the CERN IRRAD facility and at RARiS (Japan), and subsequently exposed to pion beams at the CERN SPS. Results on the performance of 3D triplet modules in their final hardware configuration are presented, with particular emphasis on test-beam measurements of hit efficiency as a function of fluence, and on charge-collection performance enabled by the Time-over-Threshold (ToT) capability of the ITkPixV2 readout chip.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.