Author/Authors :
Bashkanov، نويسنده , , M. and Clement، نويسنده , , H. and Doroshkevich، نويسنده , , E. and Khakimova، نويسنده , , O. and Kren، نويسنده , , F. and Pricking، نويسنده , , A. and Skorodko، نويسنده , , T. and Wagner، نويسنده , , G.J.، نويسنده ,
Abstract :
The first exclusive measurements at CELSIUS-WASA for the double-pionic fusion to d or 3He reveal the ABC effect–a low-mass enhancement in the π π invariant mass spectrum–to be a σ channel phenomenon associated with the formation of a Δ Δ system and combined with a resonance-like behavior in the total cross section. This quasibound system with a mass below the Δ Δ threshold obviously survives also in nuclei as a resonance configuration producing the ABC effect there.
Keywords :
? ? system , ABC effect , resonance , p n system , Isoscalar