Article

Production and detection of cold antihydrogen atoms

Istituto Nazionale di Fisica Nucleare, Sezione di Genova, Genova 16146, Italy; Physik-Institut, Zürich University, CH-8057 Zürich, Switzerland; EP Division, CERN, CH-1211 Geneva 23, Switzerland; Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark; Dipartimento di Fisica, Università di Genova, Genova 16146, Italy; Instituto de Fisica, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21945-970, and Centro Federal de Educação Tecnologica do Ceara, Fortaleza 60040-531, Brazil; Department of Physics, University of Wales Swansea, Swansea SA2 8PP, UK; Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, Pavia 27100, Italy; Dipartimento di Fisica Nucleare e Teorica, Università di Pavia, Pavia 27100, Italy; Department of Physics, University of Tokyo, Tokyo 113-0033, Japan; Dipartimento di Chimica e Fisica per l'Ingegneria e per i Materiali, Università di Brescia; Istituto Nazionale di Fisica Nucleare, Gruppo collegato di Brescia, Brescia 25123, Italy; For the ATHENA Collaboration
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 02/2004; DOI: 10.1016/j.nima.2003.10.072

ABSTRACT The production and observation of cold antihydrogen atoms have been recently reported by the ATHENA experiment at the CERN Antiproton Decelerator. The antiatoms were produced by mixing low-energy antiprotons and positrons in an electromagnetic trap. The antihydrogen detection is based on the observation of a characteristic signature in the annihilation of the neutral antiatoms on the trap walls by means of an imaging particle detector. An overview of the apparatus is given and the results obtained are discussed.

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