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Chromosomal rearrangements involving the MECOM locus, which consists of two genes MDS1 and EVI1 located at 3q26.2, are found in different types of myeloid malignancies [1,2]. Among these, the t(3;1...

The neutron calibration fields using accelerators have been developed at the Facility of Radiation Standards (FRS) of JAEA-Tokai for neutrons below 20 MeV and at Takasaki Ion Accelerators for Advanced Radiation Application (TIARA) of JAEA-Takasaki for those over 20 MeV. At FRS, monoenergetic neutrons are generated by using proton or deuteron beam from a 4 MV Van-de-Graaff (Pelletron) accelerator. Up until the present, developments of the 8, 144, 250, 565 keV, 5.0 and 14.8 MeV fields have been completed. As procedure for the development, measurement of neutron energy spectrum, peak energy and reference fluence, development of monitoring scheme for neutron fluence and establishment of the traceability on neutron fluence to the primary standards were achieved. At TIARA, three neutron fields of 45, 60 and 75 MeV are planned to be established. Quasi-monoenergetic neutrons are generated from 7Li(p,n)7Be reaction by using proton beam from an AVF cyclotron, and led into an irradiation room through a cylindrical c...

A Monte Carlo code system, MCNP-ANT, has been developed to simulate the transport of charged particles (

Calibration techniques for a gas monitor with a built-in germanium detector were studied. The peak-detection efficiencies were precisely determined with some calibration gases. In order to obtain more reliable efficiency curves from the limited data of calibration gases, an interpolation technique using a multi-γ point source was applied. And also, the feasibility of simple calibration with the point source located at an appropriate single position was discussed. As a result, the efficiencies obtained with the calibration gases show good agreement with the efficiency curves derived by the interpolation technique. The efficiencies also agreed with efficiency curves determined by the simple calibration within an error of 4%.

In general, radioactivity measurements for volume samples are performed by the γ-ray spectrometry method with germanium detectors. In the method, peak efficiency curves must be obtained for each kind of sample in advance. For the reason, usually, many standard volume sources have been made which have different shapes, densities, matrix compositions and so on. This paper describes about a simple method for determination of γ-ray efficiency curves by the combination of Monte Carlo simulations and a single-point calibration using a standard point source. This method enables us to determine the efficiency curves for various types of samples and detectors easily and precisely.