A new laser decontamination device has been developed to evaporate instantly with almost no
temperature rise and to clean up the radioisotope (RI) contaminated stainless steel components, devices
and major structural objects of nuclear power station, nuclear fuel reprocessing plants, accelerator
facilities and the related ones. The laser decontamination device delivers the tightly focused laser light
of GW/cm2 just on the surface to clean up RI contained rust mold on and inside the stress corrosion
cracks and corrosion pitting in the stainless steel-made components, devices and objects. The
decontamination device is newly designed to measure three-dimensional surface map very quickly, and
successfully to peel the three-dimensional irregular surface according to the measured map using the
three dimensional fast scanner, displacement meter and laser system. In the cold tests, the device
performed to peel off the surface of cans and multi-stepped plates very precisely, very uniformly and
Single crystal scintillator materials are widely used for detection of high-energy photons and particles.
There is continuous demand for new scintillator materials with higher performance because of increasing
number of medical, industrial, security and other applications. This article presents the recent
development of three novel inorganic scintillators; Pr-doped Lu3Al5O12 (Pr:LuAG), Ce doped Gd3 (Al,
Ga)5 O12 (Ce:GAGG) and Ce or Eu-doped 6LiCaAlF6 (Ce:LiCAF, Eu:LiCAF). Pr:LuAG shows very
interesting scintillation properties including very fast decay time, high light yield and excellent energy
resolution. Taking the advantage of these properties, positron emission mammography (PEM) equipped
with Pr:LuAG were developed. Ce:GAGG shows very high light yield, which is much higher than that
of Ce:LYSO. Survey meter using Ce:GAGG is developed using this scintillator. Ce:LiCAF and
Eu:LiCAF were developed for neutron detection. The advantage and disadvantage are discussed
comparing with halide scintillators. Eu-doped LiCAF indicated five times higher light yield than that of
existing Li-glass. It is expected to be used as the alternative of 3He.
The interest on isotopes and their applications increased in many fields such as nuclear power generation
and medicine. Laser isotope separation is a promising technique for its high selectivity and efficiency.
Isotopes of Gd and Zr, which are important materials in nuclear engineering, can be separated by
selective stepwise or multiphoton ionization method based on polarization selection rules. Development
of isotope separation of 93Zr, 126Sn, and 135Cs is desired for future nuclear transmutation of long-lived
fission products. Separation method of 48Ca by radiation pressure is proposed for double-beta- decay
The recent improvement of laser technologies will contribute to the maintenance of nuclear power plants.
The Japan Atomic Energy Agency developed a specially designed probing system was developed to
inspect and repair the cracks of the welded beads of the heat exchanger tubes of nuclear power plants.
Eddy current testing detected inner wall cracks in heat exchanger tubes. The tube thickness was 4.5 mm
and the inner diameter was 23 mm. The minimum detectable depth of the cracks was 10% of the tube
thickness. Endoscope observation confi rmed the cracks along the welded beads. Laser welding by a
300 W compact fi ber laser successfully repaired them. The probing system will operate in new nuclear
power plants with various laser monitoring technologies for coolant pipes.
Progress in laser physics and accelerator physics has enabled us to use a new generation gamma-ray
beam, namely laser Compton scattering (LCS) gamma-ray beam. The LCS gamma-ray beam has
advantages that are an energy-tunable quasi-monochromatic gamma-ray beam. We have studied a
nondestructive assay using nuclear resonance fluorescence with a LCS gamma-ray beam. This assay can
be applied to the detection of nuclear materials hidden in cargo or a container. By measuring the
amounts of the levels of oxygen, nitrogen, and carbon, the type of explosive can also be identified. We
have demonstrated the detection of lead or melamine hidden in iron shields with thicknesses of
10-15 mm. Advanced laser technology is crucial to realize a compact gamma-ray source that can be
installed in seaports.
Features and principle of function generator and characteristics of ARB (Arbitrary Waveform).
Examples of trigger oscillation and sequence oscillation with actual product. Brief explanation about
typical application in laser field.