Speaker
Description
Reliable operation of the Large Hadron Collider Beam Dumping System (LBDS) is vital for the machine safety. The role of the LBDS is to extract two counter rotating beams and to dispose of them safely on their respective 8 m long graphite dump blocks. The LBDS consists of 50 pulse generators located in the LHC galleries: each generator is connected to a kicker magnet by, 30 m long, coaxial cables. The pulse generators contain High Voltage (HV) semiconductors, which are susceptible to Single Event Burnout (SEB) - a catastrophic phenomenon for HV semiconductors - due to High Energy Hadrons (HEH). In order to better assess the HEH flux and impact, the development of an HEH monitor, based on the SEB phenomenon in HV Si diodes, is ongoing. This will improve the accuracy of SEB related failure rate estimates and will help to guide mitigation measures. A low cost acquisition system for the HEH monitor was developed. The acquisition system is based on a micro-controller continuously checking new events in up to 16 independent channels each with up to 30 HV diodes per channel: the number of channels and diodes per channel are adaptable according to the sensitivity required. To avoid false counts and coupling effects an adjustable ‘dead-time’ filter is used for each channel. Periodic ‘alive’ signals and HEH events related information, such as total number of counts, HV value, temperature and total current consumption measurements are both sent to a database, via Ethernet or Wi-Fi connection, and stored in an internal USB or SD card as a backup. In addition, the system allows remote control of the sensitivity of the monitor by modifying the voltage applied to the HV diodes. The whole system has already experienced several irradiation campaigns without any malfunction.
