Licentiate Thesis: ATLAS pixel detector readout integrated circuits and data acquisition
by
Veronica Wallängen(Stockholm University, Department of Physics)
→
Europe/Stockholm
B4:1059
B4:1059
Description
The Large Hadron Collider (LHC) is a particle collider built by the European Organization for
Nuclear Research (CERN) for testing the predictions of theories within high energy physics
and related fields, thereby contributing to advancements in our understanding of physical
laws. In order to improve the discovery potential by increasing the probability for rare events
of interest, such as Higgs boson formation, the LHC will undergo an upgrade to reach
luminosities of 5E34 cm2/s and the new machine, the so-called High Luminosity LHC, is
planned to be ready for operation around 2025. The functionality of the LHC and the
experiments installed around its circumference depends on highly advanced instrumentation
and with regards to the hardware in the ATLAS experiment, the increased collision rate and
radiation exposure following from the upgrade facilitates the need for a new detector readout
system that can meet the demands on low-mass, high-speed readout capability and radiation
tolerance, especially for the pixel detector, which is the subsystem closest to the particle
interaction point. This work describes the preparation of the ATLAS pixel detector for the
phase 2 inner tracker upgrade, in the form of testing and verification of new readout
techniques and recently developed pixel chip prototypes, as well as characterization and
simulation of a data transmission link for high-speed readout of the pixel front-ends. The
outcome of these studies is promising, as initial results indicate that the new readout schemes
as well as pixel chip prototypes are well-functioning and that a correctly designed high-speed
data transmission link can reach the desired data rates of 5 Gbps while meeting the other
challenging demands of the new system. Equally as important as the development of
improved readout electronics for an upgraded system is the maintenance and integrity
checking of the present particle detector, as well as for rigorous simulations to be carried out
with great detail and accuracy, taking into account all effects which impact the detector
functionality, in order to understand the performance of the machine. Thus, in addition to
ATLAS phase 2 upgrade activities, this thesis covers work related to the simulation of
radiation damage effects in the pixel sensors, and the update of a test bench system for
maintenance of one of the calorimeters of the ATLAS experiment.
