Direct measurement of the neutron neutron scattering cross section at the reactor YAGUAR

✍ Scribed by Furman, W I; Lychagin, E V; Muzichka, A Yu; Nekhaev, G V; Safronov, Yu V; Strelkov, A V; Sharapov, E I; Shvetsov, V N; Levakov, B G; Litvin, V I; Lyzhin, A E; Magda, E P; Howell, C R; Mitchell, G E; Tornow, W; Crawford, B E; Stephenson, S L; Bowman, C D

• Book ID: 121363965
• Publisher: Institute of Physics
• Year: 2002
• Tongue: English
• Weight: 318 KB
• Volume: 28
• Category: Article
• ISSN: 0954-3899
• DOI: 10.1088/0954-3899/28/10/308

✦ Synopsis

We propose to perform the first measurement of the neutron-neutron scattering cross section in the through-channel of the pulsed aperiodic reactor YAGUAR (Snezhinsk, Russia). Such a measurement directly determines the neutronneutron scattering length, and by comparison with the proton-proton scattering length bears upon the issue of charge symmetry of the nuclear force. The proposed experimental set-up, as well as modelling of the neutron density and of the frequency of neutron-neutron collisions is described. Experimental results are reported on the formation and optimization of the thermal neutron field inside the through-channel of the reactor YAGUAR. The instantaneous value of 1.1 × 10 18 cm −2 s −1 obtained for the thermal neutron flux density is large enough to perform the first direct neutron-neutron scattering length measurement.