In order to cope with the occupancy and radiation doses expected at the High-Luminosity LHC, the ATLAS experiment will replace its Inner Detector with an all-silicon Inner Tracker (ITk), consisting of pixel and strip subsystems. In the last two years, several prototype ITk strip modules have been tested using beams of high energy electrons produced at the DESY-II testbeam facility. Tracking was provided by EUDET telescopes. The modules tested are built from two sensor types: the rectangular ATLAS17LS, which will be used in the outer layers of the central barrel region of the detector, and the annular ATLAS12EC, which will be used in the innermost ring (R0) of the forward region. Additionally, a structure with two R0 modules positioned back-to-back has been measured, demonstrating space point reconstruction using the stereo angle of the strips. Finally, one barrel and one R0 module have been measured after irradiation to 40% beyond the expected end-of-lifetime fluence. The data obtained allow for thorough tests of the module performance, including charge collection, noise occupancy, detection efficiency, and tracking performance. The results give confidence that the ITk strip detector will meet the requirements of the ATLAS experiment.

Additional Metadata
Keywords ATLAS, HL-LHC, Particle physics, Test beam, Tracking detectors
Persistent URL dx.doi.org/10.1016/j.nima.2020.164430
Journal Nuclear Inst. and Methods in Physics Research, A
Citation
Rühr, F. (F.), Affolder, A. (A.), Ai, X. (X.), Arling, J.H. (J. H.), Atlay, B. (B.), Basso, M.J. (M. J.), … Zhu, H. (H.). (2020). Testbeam studies of barrel and end-cap modules for the ATLAS ITk strip detector before and after irradiation. Nuclear Inst. and Methods in Physics Research, A, 979. doi:10.1016/j.nima.2020.164430