Beam Loss Monitors in the Large Hadron Collider

Abstract

The LHC at CERN is the largest and most powerful particle accelerator ever built. It accelerates protons and ions at high speeds, close to the speed of light, and collides them with the purpose of recreating the conditions which could be present seconds after the Big Bang occurred. The high energy and intensity of the LHC particle beams makes them highly destructive for the machine components. Only the loss of a small fraction of the beam particles could produce a quench in the superconducting magnets or damage detector equipment. Therefore, it is essential to install a safety system which monitors the beam losses during operation of the LHC and triggers the beam dump when the losses exceed certain predetermined thresholds. These tasks are performed by the LHC BLM system, with more than 4 000 detectors covering the 27 km LHC circumference. As the BLM system is a fundamental element concerning the LHC machine protection, it is important to analyze its signal continuously in order to detect possible damage or degradation of its components, potentially caused by the high-radiation environment in which they are installed. The main objective of this work is to give an overview on both the LHC and BLM system, followed by the analysis of the BLM noise signal and the BLM integrated dose during Run 2 (2015-2018). These analysis were performed using tools created as part of this Bachelor’s Thesis. The results obtained were fundamental to determine that for the moment no BLM system limitations due to radiation effects are to be expected in future operation periods of the LHC. iv