Producing Slow Antihydrogen for a Test of CPT Symmetry with ATHENA

The ATHENA experiment at the Antiproton Decelerator facility at CERN aims at testing CPT symmetry with antihydrogen. An overview of the experiment, together with preliminary results of development towards the production of slow antihydrogen are reported.The ATHENA experiment at the Antiproton Decelerator facility at CERN aims at testing CPT symmetry with antihydrogen. An overview of the experiment, together with preliminary results of development towards the production of slow antihydrogen are reported.The ATHENA experiment at the Antiproton Decelerator facility at CERN aims at testing CPT symmetry with antihydrogen. An overview of the experiment, together with preliminary results of development towards the production of slow antihydrogen are reported.The ATHENA experiment at the Antiproton Decelerator facility at CERN aims at testing CPT symmetry with antihydrogen. An overview of the experiment, together with preliminary results of development towards the production of slow antihydrogen are reported

Detection of antihydrogen annihilations with a cryogenic pure-CsI crystal detector

In the framework of the ATHENA experiment a combined tracking and photon detector, operating close to liquid nitrogen temperatures, was developed to determine simultaneously the vertex of an antiproton annihilation and energy and direction of photons stemming from a positron annihilation. The photon detector consists of 192 pure-CsI scintillation crystals (=4 cm3) coupled to 5 x 5 mm2 avalanche photo-diodes, which are read by electronic chips realised in VLSI CMOS technology. These read out chips are also operational at liquid nitrogen temperature and feature a self-triggering capability