Speaker
Marco Bomben
(LPNHE)
Description
To extend the physics reach of the LHC, upgrades to the accelerator are planned which will allow to boost the integrated luminosity delivered to the experiments from about 700/fb to 3000/fb. To achieve this, the peak luminosity will have to rise by a factor 5 to 10 which leads to increased occupancy and radiation damage of the tracking detectors.
To cope with the elevated occupancy, the ATLAS experiment plans introduce an all-silicon inner tracker with the HL-LHC upgrade in 2021. With silicon sensors, the occupancy can be adjusted by using the appropriate unit size (pixel, strip or short strip sensors). To minimize adverse effects of radiation damage, only electron-collecting sensor designs are considered (n-in-p and n-in-n) as they are less prone to trapping.
To investigate the suitability of pixel sensors using the proven planar technology for the upgraded tracker, the ATLAS Planar Pixel Sensor R&D Project was established comprising 17 institutes and more than 80 scientists. Main areas of research are the performance of planar pixel sensors at highest fluences, the exploration of possibilities for cost reduction to enable the instrumentation of large areas, the achievement of slim or active edges to provide low geometric inefficiencies without the need for shingling of modules and the investigation of the operation of highly irradiated sensors at low thresholds to increase the efficiency.
The presentation will give an overview of the recent accomplishments of the R&D project. Among these are testbeam results obtained with n-in-n pixel sensors irradiated up to 2 1016 neq cm-2, investigations of the edge efficiency of slim-edge designs exhibiting a reduction of the inactive zone from 1100 um to only 250 um, and comparisons of these experimental findings with TCAD simulations taking into account the radiation damage. In addition, updates will be given on the status of several efforts towards fully active edges with planar technology and on a n-in-n sensor production with thicknesses varying from 150 um to 250 um.
Author
Daniel Muenstermann
(CERN/PH-ADE-ID)