A small (22.5 cm wide) plastic case with a clear lid contains a circuit board set on an aluminum mount.
The circuit board has an overall green tint. It is composed of two elements: a petalet sensor and a surrounding test frame mount. The petalet sensor consists mainly of a silver coloured surface (a short strip sensor) and two rows of six application-specific integrated circuit (ASIC) chips.
Accession Number: 2024.ph.893
Alternative Name:
Primary Materials: Silicon, Copper
Printed along the upper edge of the test frame: “Petelet [Sic] upper / lower module testframe// Based on Freiburg design// Modiefied [Sic] in Berlin 33/2014”
Dimensions (cm): Height = 3, Width =16, Length = 22.5.
This sensor is an early prototype in the development of the Inner Tracker (ITk) of the ATLAS detector being developed for the High Luminosity Large Hadron Collider (HL-LHC) upgrade to the CERN LHC. It represents part of a sensor arrangement designed to track the trajectories of particles released during the collisions of protons accelerated by the LHC.
The petalet prototyping project, a European-led initiative, involved a small scale test version of aspects of the petal sensor arrangement of the ATLAS end cap. This example was used in testing carried out University of Toronto High Energy Physics Group meant to quantify the sensor’s long term performance under conditions of intense radiation.
Condition:
Associated Instruments:
Silicon wafers for the strip sensors are made by Hamamatsu Photonics K.K., of Hamamatsu-shi, Japan.
Date of Manufacture: c. 2014
This item was among several artifacts donated by University of Toronto Professor of Physics Robert S. Orr on 31 July, 2024.
V. Benítez, M Ullán, D Quirion, G Pellegrini, C Fleta, M Lozano, D Sperlich, et al. “Sensors for the End-Cap Prototype of the Inner Tracker in the ATLAS Detector Upgrade.” Nuclear Instruments & Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment 833 (2016): 226–32.
S. Kuehn, V Benítez, J Fernández-Tejero, C Fleta, M Lozano, M Ullán, H Lacker, et al. “Prototyping of Petalets for the Phase-II Upgrade of the Silicon Strip Tracking Detector of the ATLAS Experiment.” Journal of Instrumentation 13, no. 3 (2018): T03004–T03004.
A very good summation of the ATLAS ITk strip sensor technology, as well as Canada’s contribution to the ATLAS upgrade, can be found in the following MA thesis:
Robert F. H. Hunter 2017, Development and Evaluation of Novel, Large Area, Radiation Hard Silicon Microstrip Sensors for the ATLAS ITk Experiment at the HL-LHC. MA Thesis. Carleton University. Ottawa, Ontario
The CERN Large Hadron Collider (LHC), located near Geneva Switzerland near the border with France, is the world’s largest and most powerful particle accelerator. It began operation in 2010. In 2012, researchers at the LHC announced the discover of the Higgs boson particle. The continued operation of the LHC requireds periodic upgrades to make possible investigations at higher luminosities, as well as to replace detectors that have reached the end of the finite lifespans imposed by the intense radiation environment.
The ATLAS detector is the largest of several detectors along the LHC beam line. The ATLAS ITk (Inner TracKer) is part of the ongoing high-luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN. The high-luminosity upgrade will increase the number of collisions by a factor of between 5 and 7.5. This will involve a significant increase in the radiation to which the sensor components are exposed. For this reason, the ITk design is all solid state, meaning that the design incorporates silicon detectors rather than gas detectors as in the previous Inner Detector (ID) design.
The Inner Tracker consists of an innermost pixel detector system, consisting of pixelated silicon detectors, and an outer strip detector system, incorporating silicon strip detectors such as the module shown here. The strip detector system consists of a barrel section and two end cap sections. This prototype petalet module was developed to test the strip sensor arrangement used in the petals composing the wheels of the end cap sections. The ATLAS ITk upgrade is developed through an international collaboration. Canadian collaborators will assemble and test around one quarter (~1700) of the end cap modules. The University of Toronto High Energy Physics Group focuses on quantifying the effects of radiation exposure on the performance of the sensor module. This is necessary in order to accurately interpret the readings from these sensors as the signal deteriorates due to radiation damage over the 14-year lifespan of the ITk.
As of June 2025, the ATLAS ITk is scheduled for commissioning at the beginning of LHC Run 4, the first run of the high-luminosity upgrade, in June of 2030.