Abstract: A gamma scanning apparatus includes a moving and fixing mechanism which moves/fixes a housing to a definite position, and a rotating and moving mechanism which moves a fuel assembly vertically in addition to rotating the assembly. A gamma-ray counting circuit measures an output of a gamma-ray detector, and a data collecting/analyzing and controlling apparatus analyzes data output from the gamma-ray counting circuit, in association with data relating to the rotation and movement of the fuel assembly by the rotating and moving mechanism. The rotating and moving mechanism, after fixing the vertical position of the fuel assembly with the housing also fixed, rotates the fuel assembly through 360° with its height kept constant, and during the 360° rotation of the fuel assembly, the gamma-ray counting circuit measures either a time average of count values of the detector during the rotation or an integral value within a fixed time.

Abstract: In a radiation measurement apparatus, an analog pulse signal output from a semiconductor radiation detector is converted to a plurality of digital signals by an analog-to-digital converter for each analog pulse signal. A threshold circuit for inputting these digital signals discriminates digital signals exceeding a threshold value. A digital signal integration circuit integrates the plurality of discriminated digital signals for each analog pulse signal and obtains an integrated value for each analog pulse signal. A spectrum generation circuit for inputting the respective integrated values generates a radiation energy spectrum using the integrated values and accurately performs the quantitative analysis and energy analysis of a radioactive nuclide using the radiation energy spectrum. A quantitative analysis and an energy analysis of a radioactive nuclide can be accurately performed while a time resolution of a radiation detector can be maintained.

Abstract: A gamma scanning apparatus includes a moving and fixing mechanism which moves/fixes a housing to a definite position, and a rotating and moving mechanism which moves a fuel assembly vertically in addition to rotating the assembly. A gamma-ray counting circuit measures an output of a gamma-ray detector, and a data collecting/analyzing and controlling apparatus analyzes data output from the gamma-ray counting circuit, in association with data relating to the rotation and movement of the fuel assembly by the rotating and moving mechanism. The rotating and moving mechanism, after fixing the vertical position of the fuel assembly with the housing also fixed, rotates the fuel assembly through 360° with its height kept constant, and during the 360° rotation of the fuel assembly, the gamma-ray counting circuit measures either a time average of count values of the detector during the rotation or an integral value within a fixed time.

Abstract: At a worksite of a client, progeny nuclides of radon and thoron are collected into a filter, then making the gross measurement on ?-ray amount within an hour from the collection. Next, the filter is sent to an analysis center with information added thereto, such as collection-condition information, gross-measurement information, and sampling-worksite information. At the analysis center, the gross measurement on the filter sent thereto is made again. Also, the radioactive-nuclide analysis is made to perform evaluation of the radioactivity intensity. Moreover, radon amount and thoron amount at the measurement-specimen sampling points-in-time at the worksite are calculated, then reporting the analysis result of the radon and thoron amounts to the client.

Abstract: A fuel assembly radiation measuring apparatus has a radiation signal generation apparatus including a LaBr3(Ce) scintillator, an A/D converter, a signal processing apparatus, and a data analysis apparatus. The signal processing apparatus has a FPGA and a CPU. ? rays emitted from a fuel assembly disposed in water in a fuel pool enter into the LaBr3(Ce) scintillator that emits scintillator light, then a photomultiplier tube converts the light into an electric signal as a radiation detection signal. A pulse height analyzer of the FPGA inputs a radiation detection signal having a digital waveform generated by the A/D converter and changes the digital waveform into a trapezoid waveform to obtain a maximum peak value. The data analysis apparatus quantifies a target nuclide using a plurality of inputted maximum peak values to obtain burnup.

Abstract: At a worksite of a client, progeny nuclides of radon and thoron are collected into a filter, then making the gross measurement on ?-ray amount within an hour from the collection. Next, the filter is sent to an analysis center with information added thereto, such as collection-condition information, gross-measurement information, and sampling-worksite information. At the analysis center, the gross measurement on the filter sent thereto is made again. Also, the radioactive-nuclide analysis is made to perform accurate evaluation of the radioactivity intensity. Moreover, radon amount and thoron amount at the measurement-specimen sampling points-in-time at the worksite are calculated, then reporting the analysis result of the radon and thoron amounts to the client.

Abstract: In a charged particle detector, the vacuum barrier can be reduced in size and a multichannel configuration is possible. A charged particle detector includes a metallic frame having one or more holes formed therein, a light transmitting member fixed in each of the holes of the metallic frame, an inorganic scintillation element fixed on a surface of the light transmitting member, the surface being on a first side of the member; and a photodetector disposed on a surface of the light transmitting member, the surface being on a second side opposing the first side of the member. Charged particles having passed through the inorganic scintillation element are sent via the light transmitting member to the photodetector and are detected by the photodetector.

Abstract: In a charged particle detector, the vacuum barrier can be reduced in size and a multichannel configuration is possible. A charged particle detector includes a metallic frame having one or more holes formed therein, a light transmitting member fixed in each of the holes of the metallic frame, an inorganic scintillation element fixed on a surface of the light transmitting member, the surface being on a first side of the member; and a photodetector disposed on a surface of the light transmitting member, the surface being on a second side opposing the first side of the member. Charged particles having passed through the inorganic scintillation element are sent via the light transmitting member to the photodetector and are detected by the photodetector.