The use of FPGA in drift chambers for data transfer rate reduction

Abstract

The widespread use in drift chambers of light helium-based gas mixtures is aimed to minimize the multiple scattering contribution to the momentum measurement for low momentum particles. However, because of the limited number of ionization clusters produced, these gas mixtures introduce a substantial bias in the impact parameter estimate, particularly for short impact parameters and small drift cells. Recently, an alternative impact parameter reconstruction technique (Cluster Timing) has been proposed, which consists in using, with statistical considerations, the distribution of the drift times of all individual ionization clusters, to reduce the bias and, consequently, to improve the spatial resolution. A hardware test of such application is illustrated with the details of the applied algorithm.