Fast cluster reconstruction in the NA62 Liquid Krypton electromagnetic calorimeter by using soft core embedded processors in FPGA

The NA62 experiment at CERN SPS aims to increase the precision in the measure of the Branching Ratio of the K
⁺
→ π
⁺
vv̅ decay. Efficient veto systems are needed to achieve the required background suppression level. The LKr, covering the angular range 1-10 mrad, is part of system vetoing photons due to π
⁰
decay (from K
⁺
→ π + π
⁰
). This paper deals with the implementation of the LKr L0 trigger peak reconstruction algorithm on FPGA by using a mixed architecture based on soft core embedded processors together with custom VHDL modules. This solution allows an efficient and flexible reconstruction of the energy-deposition peak.