Eur. Phys. J. A (2006) 28: 245-249
https://doi.org/10.1140/epja/i2006-10051-7

Hadron Physics

Two-pion production in deuteron-deuteron collisions at low energies

¹ Department of Radiation Sciences, Box 535, S-751 21, Uppsala, Sweden
² Department of Physics & Astronomy, UCL, WC1E 6BT, London, UK

^* e-mail: cw@hep.ucl.ac.uk

Received: 7 April 2006
Accepted: 24 May 2006
Published online: 20 June 2006

Abstract

The cross-section for the dd →^4Heππ reaction is estimated near threshold in a two-step model where a pion created in a first interaction produces a second pion in a subsequent interaction. This approach, which describes well the rates of 2π and η production in the pd →^3Heππ and dd →^4Heη reactions, leads to predictions that are much too low compared to experiment. Alternatives to this and the double-Δ model will have to be sought to explain these data.