Abstract: Provided are a neutron monitor device and a neutron measurement method which make it easier to measure the intensity of the neutrons having the energy region of 10 KeV to several hundreds KeV. A neutron monitor device includes a first detector which includes a hemispherical first body formed of PE and having a radius of 31 mm, a first specimen containing GaN disposed at the center of the first body, a Cd layer provided on an outer surface of the first body, and a B layer provided inside the first body, and a second detector which includes a hemispherical second body formed of PE and having a radius of 27 mm, a second specimen containing GaN disposed at the center of the second body, a B layer provided on the outer surface of the second body, and a Cd layer provided inside the second body.

Abstract: The neutron irradiation apparatus includes an introduction tube for introducing a proton beam, a target structure provided in a lower end of the introduction tube, an aluminum fluoride layer disposed below the target structure in an irradiation path of neutrons generated in the target structure, and a heavy water layer placed under the aluminum fluoride layer in layers. The aluminum fluoride layer is set at a thickness that increases epithermal neutrons. Since use of only the aluminum fluoride layer increases its thickness too much, heavy water is placed. Heavy water moderates neutrons quickly, and allows increasing epithermal neutrons without increasing the thickness. The combination of the aluminum fluoride layer and the heavy water layer allows increasing epithermal neutrons by attenuating only fast neutrons without increasing thermal neutrons. Accordingly, neutron flux with many epithermal neutrons is obtained.

Abstract: Provided are a neutron monitor device and a neutron measurement method which make it easier to measure the intensity of the neutrons having the energy region of 10 KeV to several hundreds KeV. A neutron monitor device includes a first detector which includes a hemispherical first body formed of PE and having a radius of 31 mm, a first specimen containing GaN disposed at the center of the first body, a Cd layer provided on an outer surface of the first body, and a B layer provided inside the first body, and a second detector which includes a hemispherical second body formed of PE and having a radius of 27 mm, a second specimen containing GaN disposed at the center of the second body, a B layer provided on the outer surface of the second body, and a Cd layer provided inside the second body.

Abstract: Provided are a gamma-ray measurement device and a gamma-ray measurement method which perform a gamma-ray measurement of simple and inexpensive structure in a mixed field of neutrons and gamma-rays. A gamma-ray measurement device is used in a method for measuring the dose in the same place when using a lead filter and when not using the filter, and obtaining a gamma dose from a difference. The gamma-ray measurement device includes a first detector which is made up of the lead filter for shielding gamma-rays and a glass dosimeter disposed in the center of the filter, and a second detector that is made up of only the glass dosimeter.

Abstract: The neutron irradiation apparatus includes an introduction tube for introducing a proton beam, a target structure provided in a lower end of the introduction tube, an aluminum fluoride layer disposed below the target structure in an irradiation path of neutrons generated in the target structure, and a heavy water layer placed under the aluminum fluoride layer in layers. The aluminum fluoride layer is set at a thickness that increases epithermal neutrons. Since use of only the aluminum fluoride layer increases its thickness too much, heavy water is placed. Heavy water moderates neutrons quickly, and allows increasing epithermal neutrons without increasing the thickness. The combination of the aluminum fluoride layer and the heavy water layer allows increasing epithermal neutrons by attenuating only fast neutrons without increasing thermal neutrons. Accordingly, neutron flux with many epithermal neutrons is obtained.

Abstract: A electromagnetic pump is configured that a housing includes therein an outer cylinder made of stainless steel, an inner cylinder made of stainless steel and arranged inside the outer cylinder, and an electromagnetic coil arranged around the outer cylinder. The outer cylinder is configured as a conical frustum having a large diameter in the inlet side and a small diameter in the outlet side. Similarly, the inner cylinder has a large diameter in the inlet side and a small diameter in the outlet side. A duct is formed between the outer cylinder and the inner cylinder. The radial cross sectional area of the duct is large in the inlet side and small in the outlet side.

Abstract: The known reflecting mirror for a laser beam conisting of a mirror base member and a high-reflectivity metal coating layer formed on the mirror base member for reflecting a laser beam, is improved so as to maintain a high mirror reflectivity without necessitating a cooling facility. The improvements reside in that a coating layer having a small diffusion coefficient is provided on the back surface side of the high-reflectivity metal coating layer, and/or in that at least one layer of dielectric coating layer or layers are provided on the surface of the high reflectivity metal coating layer.