We report on a high-statistics measurement of the basic double pionic fusion
reaction $pn o dpi^0pi^0$ over the energy region of the so-called ABC
effect, a pronounced low-mass enhancement in the $pipi$-invariant mass
spectrum. The measurements were performed with the WASA detector setup at COSY.
The data reveal the ABC effect to be associated with a Lorentzian shaped energy
dependence in the integral cross section. The observables are consistent with a
resonance with $I(J^P) =0(3^+)$ in both $pn$ and $DeltaDelta$ systems.
Necessary further tests of the resonance interpretation are discussed.
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.