Test beam evaluation of silicon strip modules for ATLAS phase-II strip tracker upgrade
The planned High Luminosity Large Hadron Collider is being designed to maximise the physics potential of the LHC with 10 years of operation at instantaneous luminosities of 7.5×10 34 cm ¿2 s ¿1 . A consequence of this increased luminosity is the expected radiation damage requiring the tracking detectors to withstand hadron fluence to over 1×10 15 1 MeV neutron equivalent per cm 2 in the ATLAS Strips system. Fast readout electronics, deploying 130 nm CMOS front-end electronics are glued on top of a silicon sensor to make a module. The radiation hard n-in-p micro-strip sensors used have been developed by the ATLAS ITk Strip Sensor collaboration and produced by Hamamatsu Photonics. A series of tests were performed at the DESY-II test beam facility to investigate the detailed performance of a strip module with both 2.5 cm and 5 cm length strips before irradiation. The DURANTA telescope was used to obtain a pointing resolution of 2 ¿m, with an additional pixel layer installed to improve timing resolution to ~25 ns. Results show that prior to irradiation a wide range of thresholds (0.5¿2.0 fC) meet the requirements of a noise occupancy less than 1×10 ¿3 and a hit efficiency greater than 99%. © 2018 ; The research was supported and financed in part by Canada Foundation for Innovation, the National Science and Engineering Research Council (NSERC) of Canada under the Research and Technology Instrumentation (RTI) grant SAPEQ-2016-00015; the National Key Program for S&T Research and Development (Grant No. 2016YFA0400101) of China and CAS-Helmholtz Joint Research Group; theMinistry of Education, Youth and Sports of the Czech Repub87lic coming from the projectLM2015058 - Research infrastructure for experiments at CERN; the DST/NRF in South 88 Africa; the Spanish Ministry of Economy and Competitiveness through the Particle Physics National Program, ref. 89 FPA2015-65652-C4-4-R (MINECO/FEDER, UE), and co-financed with FEDER funds; the UK's Science and Tech90nology Facilities Council; USA Department of Energy, Grant DE-SC0010107; and the European Union's Horizon 2020 Research and Innovation programme under Grant Agreement no. 654168. The measurements leading to these results have been performed at the Test Beam Facility at DESY Hamburg (Germany), a member of the Helmholtz Association (HGF).