Nuclear radiation detector

Geiger-Mtfller Counter or Tube. A common form of nuclear radiation detector, also serving for measuring the intensity of radiation such as of X-rays, y-rays, etc. It is particularly suitable for monochromatic beams. The device usually consists of a tubular cathode with a coaxial center wire anode, filled with a gas (such as argon plus oxygen or argon plus hydrogen) at less than arm pressure. 

P4. Parker, R. P., Semiconductor nuclear radiation detectors. Phys. Med. Biol. 15, 605-620 (1970). 

J.E. Eberhardt, R.D. Ryan and A.J. Tavendale, Evaluation of n-GaAs for nuclear radiation detectors , Nucl. Inst. Meth. 94 (1971) 463... 

Scintillation counters and germanium detectors are two types of sophisticated nuclear radiation detectors which depend upon the interaction of radiation with solid materials, such as Nal (Tl) crystals or germanium solid state diodes. They have the ability to distinguish the energies of the radiation and have a higher sensitivity to radiation than the materials discussed heretofore. They also require sophisticated instrumentation associated with their use and are expensive. 

In principle. X-ray fluorescence (XRF) per se is an atomic analytical technique, rather than a nuclear one, since it is based on electron transitions outside atomic nucleus. However, XRF is often defined as a nuclear-related technique, as frequently mentioned in many technical documents issued by the International Atomic Energy Agency, mainly because XRF is used where there are radioactive isotopic sources or accelerators, and even in large synchronous radiation facilities. Further, the detection of X-rays almost always needs nuclear radiation detectors, like Si(Li) or other planar detectors. 

Franks, R.B. James, 2001, Cadmium zinc telluride and its use as a nuclear radiation detector material . 

The M.I.P. 10 is a portable, battery- or malns-operated survey meter, equipped with various types of nuclear radiation detectors. It can be used as a dose-rate monitor, if calibrated. 

Lead sesquioxide is used as an oxidation catalyst for carbon monoxide ia exhaust gases (44,45) (see Exhaust control), as a catalyst for the preparation of lactams (46) (see Antibiotics, P-lactams), ia the manufacture of high purity diamonds (47) (see Carbon, diamond-natural), ia fireproofing compositions for poly(ethylene terephthalate) plastics (48), ia radiation detectors for x-rays and nuclear particles (49), and ia vulcanization accelerators for neoprene mbber (50). 

CdTe is used ia iafrared optics (41), phosphors, elelctroluminescent devices, photocells, and as a detector for nuclear radiation (42). 

Henshaw DL (1989) Application of sohd state nuclear track detectors to measurements of natural alpha-radioactivity in human body tissues. Nucl Tracks Radiat Meas 16(4) 253-270 Int J Radiat Appl lustrum Part D... 

Recognizing that nuclear materials are widely available and the terrorists interests in radiological and nuclear devices, the United States Congress appropriated 300 million to the Department of Homeland Security to install radiation detectors at U.S. borders. Through 2005, DHS had installed 470 radiation portal monitors throughout the country including mail facilities and land and sea entries into the United States. The U.S. has also supported the installation of detectors at the borders of the states of the former Soviet Union through its Departments of State,... 

Particle-induced X-ray emission (PIXE) is an analytical technique based upon observing fluorescent X-rays. As such, it really is not a nuclear technique since it involves an atomic process, X-ray emission. But the atomic electron shell vacancies that are filled when the X-ray is emitted are created using particle-accelerator beams and one uses typical semiconductor radiation detectors, Si (Li) detectors, to detect the X-rays. 

At this point we have described nuclear transitions and reactions that produce various forms of nuclear rad iation. The radiation propagates out from the originating nucleus and interacts with other matter along its path. These interactions with external matter allow us to observe the radiation, and its effects, and to determine the nature of the transition inside the nucleus. The interaction of radiation with matter is also the cause of chemical, physical, and biological changes that concern the public at large. We will specifically address the operating principles of radiation detectors in the next chapter, but first we will consider the fundamental interactions of nuclear radiation with matter. 

As mentioned at the beginning of this section, the primary ionization must be collected to make a direct measurement of the energy of nuclear radiation. Condensed phases have higher densities than gases and so provide more efficient stopping of the radiation per unit length. However, metals allow rapid recombination of the elec-tron/positive ion pairs and insulators inhibit the collection of the charge. Therefore, only semiconductors have been used extensively for radiation detectors. Metals and... 

Nuclear track detectors are very simple and very efficient detectors of rare events that produce highly ionizing radiation. Carefully prepared and scanned track detectors have been used to identify individual rare decays. The detectors are integrating in that the damage caused by a track is not spontaneously repaired. The drawback to track detectors is that the tracks are small and can only be observed with a microscope. In the past, scanning by eye was extremely labor intensive and prone to error. Modern computer-controlled scanning has improved the speed and reliability of the analysis. Plastic track detectors that are sensitive to a particles are used extensively in commercial radon detectors. 

Detector Sensitivity. Detectors for nuclear radiation have been under rapid and continuous development during the last decade 12). The de-... 

We must therefore rely on detectors of one sort or another to determine the amount of ionizing radiation present. It is outside of the scope of this book to discuss the wide variety of radiation detectors. Suffice it to say, there are many types of devices for detecting and quantifying the various types of ionizing radiation. The interested student should consult a modern nuclear chemistry textbook for more details regarding radiation detection and instrumentation. 

Measurements of liquid density are closely related to quantity and liquid-level measurements since both are often required simultaneously to establish the mass contents of a tank, and the same physical principle may often be used for either measurement, since liquid-level detectors sense the steep density gradient at the liquid-vapor interface. Thus, the methods of density determination include the following techniques direct weighing, differential pressure, capacitance, optical, acoustic, and nuclear radiation attenuation. In general, the various liquid level principles apply to density measurement techniques as well. 

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