Real-Time Particle Identification in Liquid Xenon

We present a field-programmable gate array (FPGA)-based technique for the on-line identification of highly ionizing particles in a liquid xenon (LXe) detector. The method was developed and successfully exploited to select alpha particles emitted by Am-241 sources submerged in LXe in an overwhelming, mostly beam-related, gamma-ray background. After revising the main features of xenon and other liquid noble gases as ultra-violet (UV) scintillating media, we describe the algorithm idea and its firmware implementation. We then present the results in terms of efficiency and background suppression for the real-time alpha-particle tagging and the limits of the MEG trigger configuration. Finally, we show that in MEG II we are going to overcome the main issues and further improve the performances.

Automated summary

This study introduces a FPGA-based technique for identifying highly ionizing particles in a liquid xenon detector. The algorithm and firmware implementation are described, showing promising results in terms of efficiency and background suppression for real-time alpha-particle tagging and MEG trigger configuration limits. Future improvements are expected in MEG II to overcome main issues and enhance performance.