Calibration and Optimisation of Timepix3 Hybrid Pixel Detectors for the Beam Gas Ionisation Profile Monitor in the Proton Synchrotron at CERN

Particle accelerators are used for a wide field of applications. On one hand, there are large research facilities, like the CERN
accelerator complex, where the goal is to understand how the universe functions on a very small scale. Another application
are medical accelerators where proton or ion beams are used to remove cancerous cells, while minimizing damage to the
surrounding healthy tissue.
To operate accelerators it is necessary to measure basic beam parameters such as position, intensity and size. These parame-
ters are measured by instruments by means of either: 1) electromagnetic or 2) direct interaction with the beam. Measurement
of the beam profile (or size) is particularly challenging since it typically requires direct interaction with the beam, which disturbs
the beam and can damage the instrument itself. Over the past years, a new beam profile monitor has been developed at CERN
based on the detection of rest gas ionisation electrons.
The Beam Gas Ionisation (BGI) Monitor (https://bgi.web.cern.ch/) is based on the detection of rest gas ionisation elec-
trons with Timepix3 Hybrid Pixel Detectors (HPDs).These detectors are mounted inside the ultra-high vacuum (UHV) of the
beam-pipe, where the detectors must tolerate: 1) electromagnetic interference from the beam; 2) radiation and 3) switching
on and off of a dipole magnet. Due to this environment, the properties of the HPDs can change over time. Consequently, also
the accuracy of the created beam profiles can change. In order to ensure a good measurement long term, certain parameters
of the chips and the detector have to be monitored. If a parameter changes outside of its bounds, the instrument has to be
recalibrated.
Currently, a new readout chain is in development. The main processing component in this chain will be a Xilinx Zynq UltraS-
cale+ MPSoC. This chip will allow the readout processing, monitoring and control procedures to be split between the FPGA
part, the Real-Time core and the Dual-Core ARM processor.
In this Master thesis, the following tasks have to be performed:
• Familiarisation with the BGI, especially the implemented calibration and controlling software
• Implementation of Python bindings for the C++ driver
• Implementation of an expert GUI in PyQt
• Automation and improvement of calibration procedures:
- DAC voltage adjustments
- Communication setup
- Implementation of an algorithm to perform equalization of the response across the pixel matrix
• Conceptualization and implementation of periodic health checks
- Research of which parameters affect the instruments performance
- Defining of acceptable boundaries for parameters
- Implementation of code, mostly in the Zynq Real-Time core, to check the parameters against these boundaries
• Communication within a heterogeneous multi-core processor
- Implementation of inter-core communication using standard-compliant methods and libraries