Author/Authors :
Nunomiya، نويسنده , , T and Nakao، نويسنده , , N and Wright، نويسنده , , P and Nakamura، نويسنده , , T and Kim، نويسنده , , E and Kurosawa، نويسنده , , T and Taniguchi، نويسنده , , S and Sasaki، نويسنده , , M and Iwase، نويسنده , , H and Uwamino، نويسنده , , Y and Shibata، نويسنده , , T and Ito، نويسنده , , S and Perry، نويسنده , , D.R، نويسنده ,
Abstract :
A deep penetration experiment through a thick bulk shield was performed at an intense spallation neutron source facility, ISIS, of the Rutherford Appleton Laboratory (RAL), United Kingdom. ISIS is a 800 MeV–200 μA proton accelerator facility. Neutrons are produced from a tantalum target, and are shielded with approximately 3-m thick steel and 1-m thick ordinary concrete. On top of the shield, we measured the neutron flux attenuation through concrete and iron shields, which were additionally placed up to 120-cm and 60-cm thickness, respectively, using activation detectors of graphite and bismuth. The attenuation lengths of concrete and iron for high-energy neutrons above 20 MeV were obtained from the 12C(n, 2n)11C reaction of graphite.
