[en] The aim of the invention is to suggest a process for treating cadmium telluride material so as to increase its resistivity and make radiation detectors by depositing on the material so treated a metallic contact, by any metal. The special characteristic of this process is the volume doped with a halogenide selected in the group formed by TeCl₄, TeBr₄ and TeI₄ and that, after cutting up, the samples are sensitized on at least a part of their surface by means of a chemical bath containing potassium cyanide, silver cyanide and ammonia, so as to create a thin film of tellurium having an appreciable conductivity

[en] This addendum refers to miniature nuclear detectors which can work on low voltages and can record with great efficiency and simultaneously alpha, beta and gamma rays as well as slow or fast thermal neutrons. The invention concerns a process for treating cadmium telluride crystals (CdTe) used in such detectors in order to suppress polarisation phenomena. The surface of the material is first heated mechanically by fine grinding or polishing, after which the surface is treated chemically and finally a thin insulating coat topped with at least one coat of a good conducting material is applied. This produces a final structure of the good conducting-insulating-semi-conducting metal or material type

No abstract available

[en] Portable device for measuring ionizing radiations which includes, a detector, amplifying facilities, electronic compensation facilities, and a visual display for showing the radiation dose received by the detector, as well as facilities for calculating the radiation dose received during a period of time, called integration time, which is shown on the visual display

No abstract available

[en] The use of a portable scanner to measure loss of bone mineral during periods of prolonged bedrest or weightlessness is described. The unit employs CdTe detectors to measure the transmission of a collimated beam of 27.5keV X-rays from I-125 which is located opposite the collimated detector. It is demonstrated that in this way, very precise measurements of bone mineral content can be made, using a battery operated portable miniature instrument

[en] Localization of radioactive hot spots is a crucial issue for nuclear industry and a challenging topic for the research-development community. Gamma cameras are systems of great interest for this type of applications. In this article, we present the main steps related to the development of an ultra-compact version of the GAMPIX technology, called Nanopix. The Nanopix prototype is based on 3 main building blocks. The first one is the Timepix pixelated chip (256 pixels * 256 pixels, 1 mm CdTe substrate) which enables a direct conversion from gamma-ray to electrical signal. The second one is a MURA coded aperture, which drastically improves the sensitivity in comparison with a pinhole collimator. The last one is a USB interface enabling to obtain a fast and easy deployment of the gamma camera. Nanopix global weight is only 268 g making this system the lightest gamma camera in the world at the current time. We will also illustrate experimental performances obtained in laboratory conditions and during in-situ measurements. Future evolutions of this gamma camera will be finally exposed. (authors)

[en] A collaboration agreement has been signed between CEA and Saint-Gobain to study the feasibility of CdZnTe semiconductor to be used in gamma cameras involved in medical imaging. The aim is a reduction of the camera size by replacing the standard scintillators and photomultiplier tubes by a matrix of semiconductor detectors. (A.C.)

No abstract available

No abstract available