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Quantification and mapping possibilities of lithium in geological material, by Nuclear Reaction Analysis (NRA), was evaluated at the Lund Ion Beam Analysis Facility (LIBAF). LiF and two Standard Reference Materials, (SRM 610 and SRM 612) were used in the investigation. The main part of the data was obtained at the beam energy 635 keV studying the high Q-value reaction 7 Li(p, α ) 4 He, but reaction yield and detection limits were also briefly investigated as a function of the energy. A double-sided silicon strip detector (DSSSD) was used to detect the α -particles emitted in the reaction in the backward direction. The combination of the high Q-value, a reasonably good cross-section and the possibility to use a high beam current have been demonstrated to allow for measurement of concentrations down below 50 ppm. Proton energies below 800 keV were demonstrated to be appropriate energies for extracting lithium in combination with boron analysis. [ABSTRACT FROM AUTHOR]

The possibility to study variations in the oxygen isotopic ratio with photon tagged nuclear reaction analysis (pNRA) is evaluated in the current work. The experiment described in the article was performed at Lund Ion Beam Analysis Facility (LIBAF) with a 2 MeV deuteron beam. Isotopic fractionation of light elements such as carbon, oxygen and nitrogen is the basis of many analytical tools in hydrology, geology, paleobiology and paleogeology. IBA methods provide one possible tool for measurement of isotopic content. During this experimental run we focused on measurement of the oxygen isotopic ratio. The measurement of stable isotopes of oxygen has a number of applications; the particular one driving the current investigation belongs to the field of astrogeology and specifically evaluation of fossil extraterrestrial material. There are three stable isotopes of oxygen: 16 O, 17 O and 18 O. We procured samples highly enriched with all three isotopes. Isotopes 16 O and 18 O were easily detected in the enriched samples, but no significant signal from 17 O was detected in the same samples. The measured yield was too low to detect 18 O in a sample with natural abundances of oxygen isotopes, at least in the current experimental setup, but the spectral line from the reaction with 16 O was clearly visible. [ABSTRACT FROM AUTHOR]

Abstract: The biogenicity of ancient morphological microfossil-like objects can be established by linking morphological (e.g. cell remnants and extracellular polymeric matrix) and chemical (e.g. isotopes, biomarkers and biominerals) evidence indicative of microorganisms or microbial activity. We have developed a non-destructive micro-analytical ion beam system capable of measuring with high spatial resolution the stable carbon isotope ratios of thin samples used for transmission electron microscopy. The technique is based on elastic scattering of alpha particles with an energy of 2.751MeV. At this energy the 13C cross section is enhanced relative to the pure Rutherford cross section for 13C, whereas the 12C cross section is reduced relative to its pure Rutherford cross section. Here we report the initial results of this experimental approach used to characterize ultramicrotomed sections of sulfur-embedded graphite and microbial cells. [Copyright &y& Elsevier]

With the recent advances towards modern Ion Beam Analysis (IBA), going from one- or few-parameter detector systems to multi-parameter systems, it has been necessary to expand and replace the more than twenty years old CAMAC based system. A new VME multi-parameter (presently up to 200 channels) data acquisition and control system has been developed and implemented at the Lund Ion Beam Analysis Facility (LIBAF). The system is based on the VX-511 Single Board Computer (SBC), acting as master with arbiter functionality and consists of standard VME modules like Analog to Digital Converters (ADC’s), Charge to Digital Converters (QDC’s), Time to Digital Converters (TDC’s), scaler’s, IO-cards, high voltage and waveform units. The modules have been specially selected to support all of the present detector systems in the laboratory, with the option of future expansion. Typically, the detector systems consist of silicon strip detectors, silicon drift detectors and scintillator detectors, for detection of charged particles, X-rays and γ-rays. The data flow of the raw data buffers out from the VME bus to the final storage place on a 16 terabyte network attached storage disc (NAS-disc) is described. The acquisition process, remotely controlled over one of the SBCs ethernet channels, is also discussed. The user interface is written in the Kmax software package, and is used to control the acquisition process as well as for advanced online and offline data analysis through a user-friendly graphical user interface (GUI). In this work the system implementation, layout and performance are presented. The user interface and possibilities for advanced offline analysis are also discussed and illustrated. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we present an investigation of to perform simultaneous measurements of the D/H-ratio by coincidence measurements using proton–proton scattering and proton–deuteron scattering or deuteron–deuteron scattering and deuteron–proton scattering. This is performed with the use of a double sided silicon strip detector (DSSSD), which provides both position information and energy information. The different approaches are evaluated by measurements on deuterated polyethylene targets with known D/H-ratios. Signals from both deuterium and hydrogen were observed during measurements and the best results were achieved with a beam of deuterons. [Copyright &y& Elsevier]

A focused MeV proton beam at the Lund Ion Beam Analysis Facility has been used to induce radiation damage in transmission semiconductor detectors. The damage alters the response of detectors and degrades their charge transport properties. In this work, the radiation tolerance of ultra-thin silicon PIN detectors was studied as a function of proton fluences and detector thickness using a scanning proton microprobe. The investigated detectors had thicknesses ranging between 6.5 and 22 μm, and different selected regions of each detector were irradiated with fluence up to 2 × 10 15 protons/cm 2 . The results show that the charge collection efficiency (CCE) decreases as a function of the proton fluence. Compared with non-irradiated regions, the CCE was above 94% at the lowest fluence of 2 × 10 12 protons/cm 2 for all the detectors studied. Degradation of the devices caused spectral peak shifting toward lower energies. The highest possible fluence of 2.55 MeV protons that could be used, causing only minor radiation damage, was 2 × 10 13 cm −2 for the thinnest detectors (6.5 and 10 μm) and 2 × 10 12 cm −2 for the thickest detectors (15 and 22 μm). [ABSTRACT FROM AUTHOR]

Highlights: [•] The characteristics of new ΔE detectors for tracking the protons were reported. [•] The tested detectors have been shown very low noise and good energy resolution. [•] The new devices have proved a high hit detecting efficiency for MeV protons. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the characterisation of an ultra-thin silicon semiconductor ΔE detector to be used as a pre-cell ion hit detector in single ion experiments on individual, living cells. The characteristics of interest for this specific application are the hit detection efficiency, which has to be close to 100% to enable bombardment with either a single ion or a counted number of ions, the beam spreading, which should be as small as possible to maintain the targeting accuracy, and the vacuum tightness, since the detector is intended, if possible, to be used simultaneously as vacuum window. The hit detection efficiency was shown to be above 99% when detecting alpha particles or 2MeV protons, the increase in beam size was about 1μm and the vacuum tightness was comparable to that of the Si3N4 wafer which is normally used as vacuum window, thus the ΔE detector fulfils the main criteria to function properly as a single ion hit detector. [Copyright &y& Elsevier]

Abstract: Currently, a single ion hit facility, for irradiation of single cells with single, light MeV ions is under development at the Lund Nuclear Microprobe. In this paper, a novel approach to the ion detection issue is presented. A silicon detector, a type utilized at other facilities for post-cell ion detection, has been investigated as a possible option for pre-cell hit detection. If proven successful, this detector could possibly also be used simultaneously as vacuum window. The first experiments carried out on the 9μm thick silicon detector, with an area of 4mm2, have been aimed at investigations of signal-to-noise ratio and efficiency. The results thus far reveal a low noise level and a noise distribution, which is well separated from the signal peak. However, the efficiency remains a problem, since at present it is far from the required 100%. [Copyright &y& Elsevier]

Abstract: Modern sunscreens contain particles like TiO2 having sizes of 25–70nm and acting as a reflecting substance. For cosmetic reasons the particle size is minimized. Questions have been raised to what degree these nano particles penetrate the skin barrier, and how they do affect the human. The EU funded project “Quality of skin as a barrier to ultra-fine particles” – NANODERM has started with the purpose to evaluate the possible risks of TiO2 penetration into vital skin layers. The purpose of the work presented here was to find the optimal conditions for micro-PIXE analysis of Ti in thin skin sections. In the skin region where Ti is expected to be found, the naturally occurring major elements phosphorus, chlorine, sulphur and potassium have steep gradients and thus influence the X-ray background in a non-predictable manner. Based on experimental studies of Ti-exposed human skin sections using proton energies ranging from 1.8–2.55MeV, the corresponding PIXE detection limits for Ti were calculated. The energy that was found to be the most favourable, 1.9MeV, was then selected for future studies. [Copyright &y& Elsevier]

Abstract: A new beam line for generating a sub-micron beam spot for high-resolution nuclear microprobe applications has been constructed at the Lund nuclear microprobe facility. In this paper, the first in a series of three, a detailed theoretical investigation of different focusing systems is presented based on calculations performed with the computer programs PRAM and OXTRACE. Comparison is made between a doublet, a triplet, a quadruplet and a split quadruplet (two-stage focusing). For the split quadruplet all four quadrupole magnets were uncoupled. The conclusion from the calculations was that to obtain the smallest possible beam, the two-stage focusing system should be used. Such a focusing system (a doublet at each stage) has been chosen for the new sub-micron set-up at the Lund NMP laboratory. The first stage focuses the beam in an intermediate chamber, which has a high-resolution optical viewing system facilitating more control over the beam spot. This real image of the first stage is then used as a virtual object for the second stage. [Copyright &y& Elsevier]

A new chamber has been designed and constructed for the second beam line at the Lund Nuclear Microprobe facility, Sweden. The aim with the chamber is to perform standardized analyses with most of the nuclear analytical techniques (proton induced X-ray emission, particle elastic scattering analysis, proton induced gamma emission, nuclear reaction analysis, etc.) with a millimetre size beam. The beam line and chamber constructions are described in this paper. The possibility to run samples in batch, and the special arrangement developed for this is described. A mass calibration of the PIXE set-up has been done with MicroMatter thin film standards and other thick standards. The spectra were acquired with CAMAC based data acquisition system with Kmax interfacing software. The GUPIX software package recently installed in our laboratory has been used to process the PIXE spectra and the results are compared with the certified values. For standardization the instrumental constant H (solid angle and correction factor) is determined relying completely on the GUPIX data base (cross-sections, fluorescence and Coster–Kronig probabilities, stopping powers and attenuation coefficients) for a large set of elements. These H values are saved inside the GUPIX library, to be used in future analysis. [Copyright &y& Elsevier]