Particle-induced y-ray emission

X-ray emission (PIXE), heavy ion-induced X-ray emission (HIXE), particle-induced y-ray emission (PIGE), Rutherford backscattering spectrometry (RBS), and elastic recoil detection analysis (ERDA). These methods are also multielemental and nondestructive. In general, when ion beam methods are used it should be kept in mind that sulfur-containing matter may be lost during the irradiation, and therefore sufficiently low beam currents should be employed. Also, sample homogeneity is vital since the volume probed by the ions is rather small. 

Particle-induced y-ray emission In PIGE, the prompt y-rays from various reactions are detected during irradiation. Tritons ( H) as well as protons have been used as bombarding particles in this application. Alpha-particles do not produce y-rays from sulfur bombardment at practical ion energies. 

Figure 5 A multidetector setup used in combination with a nuclear microprobe. Types of spectra obtained are indicated. PIGE, particle-induced y-ray emission and PBA, prompt radiation analysis. See text for further explanation.

In the following paragraph, the most commonly applied analytical methods for F detection in archaeological artefacts are presented (Table 1). In art and archaeology, the method of choice for F analysis is without any doubt particle (or pro-ton)-induced y-ray emission (PIGE, sometimes also called PIGME) [5],... 

IBA techniques, which also include Rutherford backscattering spectrometry (RBS) and particle induced X-ray emission (PIXE), require the use of a particle accelerator to produce a beam of mono-energetic MeV ions which is then incident on a target. The ions may interact with atomic electrons within the target to produce characteristic X-rays or they may collide with nuclei. If an ion collides with a nucleus it may scatter, cause the nucleus to be ejected (recoiled) or undergo a nuclear reaction resulting in the emission of particles and/or y-rays. NRA involves the detection of particles or y-rays caused by nuclear reactions in the target while ERD involves the... 

These advantages make the ion-y reactions a particularly useful elemental analysis technique. Because the detection technique is different from the detection of both X-rays in PIXE and particles in RBS and NRA, the method got in practice a distinctive name particle-induced 7-ray emission (PIGE), where the word particle means mostly proton. PIGE is often used simultaneously with PIXE, and its suitability for the analysis of light elements (mainly Li, B, F, Na, Mg, Al, and Si) complements the performance of PIXE well. Among y-ray emissions induced by various types of particles, the deuteron-induced 7-ray emission (DIGE) deserves the most practical interest, because it is also sensitive to C, N, and O, and its high cross sections... 

In addition to activation by thermal ( 0.04 eV), epithermal (>0.1eV), or fast neutrons (14MeV), a variety of charged particles (p, d, a, etc.) and y-rays have been used when special sources are available. For example, l-5MeV protons from a van de Graaff electrostatic generator produce X rays from the excited intermediate in a technique designated by the acronym FIXE (proton-induced X-ray emission), ... 

In terms of atomic spectrometry, NAA is a method combining excitation by nuclear reaction with delayed de-excitation of the radioactive atoms produced by emission of ionising radiation (fi, y, X-ray). Measurement of delayed particles or radiations from the decay of a radioactive product of a neutron-induced nuclear reaction is known as simple or delayed-gamma NAA, and may be purely instrumental (INAA). The y-ray energies are characteristic of specific indicator radionuclides, and their intensities are proportional to the amounts of the various target nuclides in the sample. NAA can thus... 

Fission. The splitting of an atomic nucleus into two fragments that usually releases neutrons and y rays. Eission may occur spontaneously or may be induced by capture of bombarding particles. Primary fission products usually decay by particle emission to radioactive daughter products. The chain reaction that may result in controlled burning of nuclear fuel or in an uncontrolled nuclear weapons explosion results from the release of 2 or 3 neutrons/fission. Neutrons cause additional fissile nuclei in the vicinity to fission, producing still more neutrons, in turn producing still... 

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