International Conference on Exotic Atoms and Related Topics - EXA2014

Producing a beam of antihydrogen, as published by the ASACUSA-Hbar collaboration[1], imposes some big experimental challenges that limit the production rate. Therefore a suitable detector needs to have very good suppression of background events. The main sources of background are upstream annihilations of antiprotons within the cusp and cosmic particles penetration the detector. These background sources are addressed by surrounding a central detector with two hodoscope layers and the requirement to trigger only if the detector records a hit in both hodoscope layers and the central detector. Additionally basic vertex reconstruction to discriminate between different quantum states of the antihydrogen atoms after the spin selection sextupole is possible. This allows to use the same detector for initial beam and trap diagnosis as well as for the final measurement of the groundstate hyperfinestructure of antihydrogen [2]. This work displays the current state of the detector and trigger developments in preparation for the upcoming beamtime in Autumn 2014 at the CERN AD facility. References: [1] N. Kuroda et. al., Nature Communications 5, 3089 (2014). [2] C. Malbrunot et. al., Hyperfine Interactions, February 2014, 1-6 (2014).