APPC12 H-1-O4
The 12th Asia Pacific Physics Conference
Performance of a Remotely Located Muon Radiography System to
Identify the Inner Structure of Nuclear Plant
Fumiaki Ito, H. Fujiia, K. Hara, H. Kakunob, S. Kim, M. Kochiyamaa,
K. Nagaminea, A. Suzukia, Y. Takada, F. Takasakia, S. Yamashitac
Univ. of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
a
KEK, Tsukuba, Ibaraki 305-0801, Japan
b
Tokyo Metropolitan Univ., Hachioji, Tokyo 192-0397, Japan
c
Univ. of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
[email protected]
As the long-term settlement procedure of Fukushima Daiichi reactor accident has
started, evaluation of the status of nuclear fuels has become one of the key issues to
provide information to work on delicate and complicated fuel removal process. Muon
radiography is to use cosmic muons for study of the inner structure of big objects[1].
We have constructed a muon radiography system consisting of 1 × 1 m tracking
planes utilizing 1 cm wide scintillator bars. The system performance was evaluated
by identifying the inner structure of a Japan Atomic Power Company nuclear plant.
The detector can reconstruct an image of the characteristic reactor structures. The
image distribution was consistent with the case where the pressure vessel was filled
with water or equivalent, and no nuclear fuel was identified in the pressure vessel.
We also measured the profile of the fuel material located in the fuel storage pool.
[1]K. Nagamine et al., Proc. of Japan Academy Series B, Vol.81,No.7(2005)257-2
(Left) The obtained image of the reactor and (Right) Horizontal distributions.
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