Imaging the Inner Structure of a Nuclear Reactor by Cosmic Muon Radiography

TL;DR

This paper demonstrates the use of cosmic muon radiography to non-invasively image the internal structure of a nuclear reactor, successfully identifying key components and fuel storage areas.

Contribution

It introduces a muon radiography method applied to a real nuclear reactor, providing detailed internal imaging without physical intrusion.

Findings

Successful identification of reactor components

Detection of nuclear fuel storage areas

Validation of muon radiography for reactor inspection

Abstract

We studied the inner structure of the nuclear reactor of the Japan Atomic Power Company (JAPC) at Tokai, Japan, by the muon radiography. In this study, muon detectors were placed outside of the reactor building. By detecting cosmic muons penetrating through the wall of the reactor building, we could successfully identify the objects such as the containment vessel, pressure vessel, and other structures of the reactor. We also observed a concentration of heavy material which can be attributed to the nuclear fuel assemblies stored in the nuclear fuel storage pool.