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Presented is a review of the accomplishments, of the light-element program, conducted at the Lund Ion-Beam Analysis Facility. A detailed account is given of the current experimental setup at the total Ion-Beam Analysis Chamber, which is equipped with two Double-Sided Silicon Strip Detectors for charge particle detection, a silicon drift detector for PIXE analysis, an electrostatic deflection system for charge measurement and implements a Nuclear Micro-Probe. A summary of the work conducted to date on the quantification of low Z elements is presented on a case by case basis. Details of the current work efforts and an overview of the advances which are intended in the near future are given. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen normally occurs as hydroxyl ions related to defects at specific crystallographic sites in the structures, and is normally characterized by infrared spectroscopy (FTIR). For quantification purposes the FTIR technique has proven to be less precise since calibrations against independent methods are needed. Hydrogen analysis by the NMP technique can solve many of the problems, due to the low detection limit, high lateral resolution, insignificant matrix effects and possibility to discriminate surface-adsorbed water. The technique has been shown to work both on thin samples and on thicker geological samples. To avoid disturbance from surface contamination the hydrogen is analyzed inside semi-thick geological samples. The technique used is an elastic recoil technique where both the incident projectile (proton) and the recoiled hydrogen are detected in coincidence in a segmented detector. Both the traditional annular system with the detector divided in two halves and the new double-sided silicon strip detector (DSSSD) has been used. In this work we present an upgraded version of the technique, studying two sets of mineral standards combined with pre-sample charge normalization. To improve the processing time of data we suggest a very simple semi-empirical approach to be used for data evaluation. The advantages and drawbacks with the approach are discussed and a possible extension of the model is suggested. [Copyright &y& Elsevier]

Abstract: The double sided silicon strip detector (DSSSD) is a segmented silicon detector commonly used in the fields of high energy physics and nuclear physics. This type of detector is used for analysis of reactions produced by charged particles. This makes it well suited for a number of analytical methods commonly used in ion beam analysis (IBA), such as Rutherford Backscattering (RBS) and elastic recoil detection (ERDA). One such detector was installed and tested at Lund Ion Beam Analysis Facility (LIBAF) recently. This is a modification to the existing setup used to measure hydrogen concentrations and depth profiles. When completed it will be used primarily for geological applications. Exact knowledge of the hydrogen content is important in a number of fields, but high enough accuracy can be difficult to achieve with most methods. In IBA normally some variant of ERDA, such as the proton–proton (p–p) coincidence method is used. We describe how the p–p coincidence technique was optimized to get the most out of our experimental setup. Previously this type of spectroscopy has been performed with two detector channels. In the present setup we expand that number from 2 to 96 channels, 64 on the front and 32 on the back of the detector. The intersecting strips give 2048 distinct detector elements or 1024 possible coincidences as dictated by the reaction kinematics. This increase in complexity requires a more detailed data analysis but it rewards us with higher sensitivity and a better background suppression. [Copyright &y& Elsevier]

Abstract: Hydrogen has been shown to occur as a trace element in many nominally anhydrous minerals. The presence of hydrogen in several of the major minerals in the Earth’s mantle has received attention, due to the possibility that these phases provide a significant hydrogen reservoir. Recently an experimental and analytical procedure for hydrogen measurements in thin mineral samples by proton–proton scattering has been developed at the Lund Nuclear Microprobe facility. An annular surface barrier detector, divided in two insulated halves, is used to detect the scattered proton and the recoiled proton in coincidence. The summed energy of each detected proton pair can be used to produce depth profiles if the individual scattering angles are known. The easiest case is when only a small difference in energy between each detected proton pair is allowed, i.e. scattering angles very close to 45°. This limitation criterion considerably reduces the statistics. For this reason the analytical method has been expanded to use the full detector area (35–55°) and to identify the scattering angles individually for each hydrogen event. Nominally anhydrous minerals, both synthesized and of natural occurrence, with hydrogen concentrations from 10 to 100ppm have been analysed. Hydrous minerals, as well as Mylar foils were used as standards. Depth profiles show that intrinsic hydrogen can be distinguished from surface contaminations, e.g. water adsorbed on the sample surfaces. [Copyright &y& Elsevier]