Eur. Phys. J. Plus (2012) 127: 125
https://doi.org/10.1140/epjp/i2012-12125-8

Regular Article

First experimental detection of antiproton in-flight annihilation on nuclei at ∼ 130 keV

¹ Max-Planck-Institut fur Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748, Garching, Germany
² Physics Department, CERN, Geneva 23, 1211, Switzerland
³ Wigner Institute for Particle and Nuclear Physics, H-1525, Budapest, Hungary
⁴ Department of Physics, University of Tokyo, 113-0033, Tokyo, Japan
⁵ Dipartimento di Chimica e Fisica per l’Ingegneria e per i Materiali, Università di Brescia, 25133, Brescia, Italy
⁶ Gruppo Collegato di Brescia, INFN, 25133, Brescia, Italy
⁷ Dipartimento di Scienze Fisiche e Matematiche, Università di Como, I-22100, Como, Italy
⁸ Sezione di Milano Bicocca, INFN, I-20126, Milano, Italy
⁹ Sezione di Trieste, INFN, I-34127, Trieste, Italy

^* e-mail: lodi@bs.infn.it

Received: 10 September 2012
Accepted: 13 September 2012
Published online: 15 October 2012

Abstract

The existing data of antinucleon-nucleon and antinucleon-nuclei annihilation cross-sections are confined to energies above about 1MeV. Experimental limitations have prevented till now the lower energies data to be achieved in spite of the interest they represent for theoretical models. One of the unresolved question concerns the antiproton annihilation cross-section measured at LEAR on light nuclei in the MeV region, which show a saturation with the mass number of the target nucleus against any naive expectation. With regard to fundamental cosmology, the knowledge of the annihilation cross-sections at energies below 1MeV can contribute to understand the matter-antimatter asymmetry in the Universe. We present here the experimental demonstration of the feasibility of the measurement of antiproton-nuclei annihilation cross-sections in the 100 keV region.