Resonant Nuclear Reaction Analysis

Acronyms RNRA (resonant nuclear reaction analysis) NRA (nuclear reaction analysis) 

The sample should be a soHd material, usually the trace elements or impurities in the bulk material are investigated. 

The spectrum of charged products of the nuclear reaction is measured. The yield of nuclear reaction products is directly dependent on the cross section (which defines the probabihty of a specific type of interaction) and the density of target atoms in the sample. 

The nuclear reaction methods are suitable for the determination of several isotopes from to S. The most frequently used reactions are (p, ), (d,p) and (d,a) providing useful alternative methods for the determination of isotopes such as D, and compared with RBS or elastic recoil detection analysis (ERDA). Alpha induced reactions have a limited use. Some Li induced reactions have been tested and the ( B, a) reaction has been used for hydrogen determination and profiling. Cross-sections of 10 to 100 mb sr are observed for proton and deu-teron induced reactions with light isotopes such as D, li. Be and B. Detection limits of the order of 10 jjg g or even less are then possible with measuring times of the order of tens of minutes. Isotopes up to S can be determined in heavier matrices at mg g levels depending on the maximum beam current that the sample can withstand. 

The use of glancing incidence or emergence for heavy incident ions or produced ions respectively can give typical depth resolutions at the surface of 10 to 100 nm. 

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PIGE is very sensitive (the limit of detection can be as low as 1 ppm) and non-destructive. It allows analysis of bulk F, F-distribution within one sample on cross-sections or depth profiles using resonant nuclear reaction analysis (RNRA) [35]. The spatial resolution, even using a beam of some micrometres size or RNRA, is however insufficient to detect F on individual bone crystals. The RNRA method is reviewed in detail in the chapter of Dobeli et al. [6] in this volume. 

Ohnuki T, Kozai N, Isobe H, Murakami T, Yamamoto S, Aoki Y, Naramoto H (1997) Sorption mechanism of emopium by apatite using Rutherford backscattering spectroscopy and resonant nuclear reaction analysis. J Nucl Sci Techn 34 58-62... 

RNRA, Resonant Nuclear Reaction Analysis, 35 RS Recoil Spectrometry, viz ERDA, 9 SALI Surface Analysis by Laser Ionisation, 39 SAM Scanning Auger Microscopy, 37... 

This overview covers the major teclnhques used in materials analysis with MeV ion beams Rutherford backscattering, chaimelling, resonance scattering, forward recoil scattering, PIXE and microbeams. We have not covered nuclear reaction analysis (NRA), because it applies to special incident-ion-target-atom combinations and is a topic of its own [1, 2]. 

Eor a non-resonant nuclear reaction with emission of an ion, a depth scale can be obtained from the measured energy of the emitted ions. If ions emitted from a depth x are lower in energy by AE than ions emitted from the surface, a relationship between AE and x can be found, similarly to RBS and ERDA analysis ... 

NEI NETPATH NFC NGCC NMR NOx NPP NRA NRC Development Nuclear Energy Institute Interactive code for modelling net geochemical reactions along a flow path Nuclear fuel cycle Natural gas combined cycle Nuclear magnetic resonance NO + N02 Nuclear power plant Nuclear reaction analysis National Research Council... 

In the following, those ion beam analysis techniques that allow for fluorine detection will be presented. By far, the most important technique in this respect is nuclear reaction analysis (NRA). Although it can be rather complex to perform, it is the most often applied technique for fluorine trace element studies, due to a number of convenient and prolific resonant nuclear reactions which make it very sensitive to fluorine in most host matrices. NRA is often combined with particle-induced X-ray emission (PIXE) which allows for simultaneous determination of the sample bulk composition and concentrations of heavier trace elements. By focusing and deflecting the ion beam in a microprobe, the mentioned techniques can be used for two- or even three-dimensional multi-elemental imaging. 

In the analysis of light elements by PIGE, the reactions by Coulomb excitation (p, p y) are common. The resonance nuclear reactions (p, y), (p, ay) are used occasionally for the depth-profile. 

Chemical diffusion of Ti under anhydrous conditions at latm and under fluid-present elevated pressures (1.1 to 1.2GPa) conditions was measured in natural zircon. Nuclear reaction analysis and the resonant nuclear reaction 48xi(p,Y)49y were used to measure diffusion profiles. The Arrhenius expression for diffusion at 1350 to 1550C and latm was ... 

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