Author/Authors :
P. Jesinger، نويسنده , , P and Kِtzle، نويسنده , , A and Gagarski، نويسنده , , A.M and Gِnnenwein، نويسنده , , F and Danilyan، نويسنده , , G and Pavlov، نويسنده , , V.S and Chvatchkin، نويسنده , , V.B and Mutterer، نويسنده , , M and Neumaier، نويسنده , , S.R and Petrov، نويسنده , , G.A and Petrova، نويسنده , , V.I and Nesvizhevsky، نويسنده , , V and Zimmer، نويسنده , , O and Geltenbort، نويسنده , , P and Schmidt، نويسنده , , K and Kor، نويسنده ,
Abstract :
In ternary fission, besides the two main fission fragments, a third (usually light) charged particle is emitted. A triple correlation has been studied involving the momenta for a specific fission fragment p̂f, the momenta of the ternary particle p̂t and the spin of the polarized cold neutron inducing fission σ̂. The correlation observable B=σ̂·[p̂f×p̂t] reverses sign upon time reversal and thus a non-vanishing value for the expectation value 〈B〉 could possibly be due to TRI being violated. However, final-state interactions or specific properties of the emission mechanism for ternary particles could equally well lead to a non-zero 〈B〉 with TRI being perfectly conserved. The reaction chosen was 233U(n,f). An unexpectedly large correlation was observed. From the raw data the value for 〈B〉 is 〈B〉=−(0.78±0.02)×10−3 with the sign corresponding to light fragments. Corrections for neutron polarization, geometric efficiency, resolution of detectors and background increase this figure by a factor of (1.5±0.3).
