ALPIDE Testing Software for the upgraded Inner Tracking System of the ALICE experiment

Abstract

ALICE, a Large Hadron Collider experiment, will be upgraded during the long shutdown in 2018/2019. The Inner Tracking System (ITS) is one of the sub-detectors of ALICE and forms the heart of the detector. Its main job is to track low momenta particles by the use of silicon detectors. During the upgrade, these silicon detectors will be replaced with modern silicon pixel chips. The demands for these chips are very high because of their harsh operating environment and therefore a higher error rate in the production than normal is expected.

In this bachelor project, a graphical interface for testing software has been designed and created to perform tests and scans on a beta-version of the ALICE Pixel Detector (ALPIDE) chip. The basic communication between the chip and the computer is provided by a library which has been written by INFN (Italy). The graphical interface uses C++ 11 and Qt 5.5.

A register, threshold and noise scan have been implemented. They test the core and individual pixels of the chip. The scans provide data on which a first prediction can be made whether the chip meets its high demands or not. During a scan, the obtained data is plotted and can be examined. The testing software and its structure provide a solid foundation for further development. The software is built on a flexible basis which allows the addition of more scans and tests. Full documentation of the code is attached in the appendix.