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1.	Nilsson, Örjan, et al. (author) Development of parallel plate channel multipliers for use in electron spectroscopy 1970 In: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 84, s. 301- Journal article (peer-reviewed)
2.	Azevedo, GD, et al. (author) Direct observation of structural relaxation in amorphous compound semiconductors 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 206, s. 1024-1027 Journal article (peer-reviewed)abstract Extended X-ray absorption fine structure measurements have been used to characterize, at the atomic level, the thermally induced structural relaxation of InAs amorphized by ion implantation. Our results are consistent with a relaxation mechanism mediated by point-defect annihilation with concomitant reduction in both chemical and structural disorder. Though relaxation yields a decrease in chemical disorder, homopolar bonding is still retained in the fully relaxed amorphous structure. (C) 2003 Elsevier Science B.V. All rights reserved.
3.	Azevedo, GD, et al. (author) EXAFS measurements of metal-decorated nanocavities in Si 2003 In: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 199, s. 179-184 Conference paper (peer-reviewed)abstract This contribution presents a sample preparation methodology to enable the identification, with synchrotron radiation-based analytical techniques, of the gettering sites of metallic impurities on the internal walls of implantation-induced nanocavities in Si substrates. Preliminary results for the Cu-Si and Cu-Cu bond lengths on the internal surface of the nanocavities are reported. (C) 2002 Elsevier Science B.V. All rights reserved.
4.	Azevedo, GD, et al. (author) Structural characterization of amorphised InAs with synchrotron radiation 2002 In: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 190, s. 851-855 Conference paper (peer-reviewed)abstract Extended X-ray absorption fine structure measurements have been utilized to determine the structural parameters of InAs amorphised by ion implantation. Relative to crystalline standards, increases in bond length and Debye-Walter factor were apparent. Our results indicate that a total coordination number of four atoms, as observed in the crystalline phase, is retained in the amorphous material. Furthermore, homopolar bonding, forbidden in the crystalline phase, is present in the amorphous material and, apparently, in amorphous III-V semiconductors in general.
5.	Bennett, J. R. J., et al. (author) Measurements of intense beams of Li-11 from a tantalum foil target 1999 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 155:4, s. 515-517 Journal article (peer-reviewed)abstract The yields of Li-11 from a tantalum target, constructed from very thin foils, have been measured at ISOLDE and found to be an order of magnitude greater than those previously measured for a standard roll foil target. The modifications to the existing target designs were based on theoretical modelling calculations. The tantalum foils are 2 mu m thick and the target mass is only one tenth of normal foil targets. (C) 1999 Elsevier Science B.V. All rights reserved.
6.	Bergmann, U. C., et al. (author) Production yields of noble-gas isotopes from ISOLDE UCx/graphite targets 2003 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 204, s. 220-224 Journal article (peer-reviewed)abstract Yields of He, Ne, Ar, Kr and Xe isotopic chains were measured from UCx/graphite and ThCx/graphite targets at the PSB-ISOLDE facility at CERN using isobaric selectivity achieved by the combination of a plasma-discharge ion source with a water-cooled transfer line. The delay times measured for a UCx/graphite target allow for an extrapolation to the expected yields of very neutron-rich noble gas isotopes, in particular for the "NuPECC reference elements" Ar and Kr, at the next-generation radioactive ion-beam facility EURISOL. (C)2003 Elsevier Science B.V. All rights reserved.
7.	Bogdanovich, P, et al. (author) Theoretical lifetimes for all states of five Cl X configurations 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 205, s. 70-73 Journal article (peer-reviewed)abstract Ab initio calculations including relativistic and correlation corrections were performed to obtain energy spectra and lifetimes for all states of first five configurations of Cl X.
8.	Bohgard, Mats, et al. (author) Calibration procedure for particle Elastic Scattering Analysis of Thin Samples 1984 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; B3, s. 268-271 Journal article (peer-reviewed)
9.	Bulow, K, et al. (author) The penetration depth and lateral distribution of pigment related to the pigment grain size and the calendering of paper 2002 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 189, s. 308-314 Journal article (peer-reviewed)abstract The interaction of ink and newspaper has been investigated and the specific question of penetration of ink into the paper has been addressed with a nuclear microprobe using particle induced X-ray emission, The penetration depth of the newsprint is a critical factor in terms of increasing the quality of newsprint and minimising the amount of ink used. The objective of the experiment was to relate the penetration depth of pigment with the calendering of the paper, The dependence of the penetration depth on the pigment grain size was also Studied, To Study the penetration depth of pigment in paper, cyan ink with Cu as a tracer of the coloured pigment was used, For the study of the penetration depth dependence of pigment size. specially grounded Japanese ink with well-defined pigment grain size was used. This was compared to Swedish ink with pigment grains with normal size-distribution, The results show that the calendering of the paper considerably affects the penetration depth of ink. (C) 2002 Elsevier Science B.V. All rights reserved.
10.	Glave, Stefan, et al. (author) Quality indicators for woodwind reed material 1999 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 150:1-4, s. 673-678 Journal article (peer-reviewed)abstract For the generation of sound, some woodwind musical instruments, e.g. oboe, bassoon, clarinet and saxophone, are provided with mouthpieces made from reeds. These reeds are the culms of Arundo donax, a tall, cane-like perennial grass. A general problem is that the material is of varying quality, yet externally differences cannot be observed. Hence, large proportions of the prepared reeds are unusable. One hypothesis is that the changes in quality are correlated with differences in the chemical and anatomical structure of the tissue. Therefore, a comparison of superior and inferior mouthpieces, used by professional musicians, was undertaken to determinate potential indicators of quality. Nuclear microprobe analysis of reeds was carried out and complemented by scanning electron and light microscopy. The elemental levels of Si, P, S, Cl, K and Ca were compared between good and poor mouthpieces using appropriate statistical tests. No statistically significant differences could be identified. Microscopical observations showed that partial occlusion of vessels by tylose formation was associated with material deemed unusable.
11.	Glover, Chris, et al. (author) Structure of amorphous silicon investigated by EXAFS 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 199, s. 195-199 Journal article (peer-reviewed)abstract The local structure of amorphous Si (a-Si) formed by ion implantation has been investigated at the Si K edge with extended X-ray absorption fine structure spectroscopy (EXAFS). The first four cumulants of the interatomic distance distribution have been determined using the Cumulant method. The structural parameters (bondlength, coordination number and Debye-Waller factor) compared favorably to previous EXAFS investigations of a-Si prepared by sputtering methods, however, in the ion implanted case, no asymmetry was detectable in the radial distribution function for a-Si. The present results are in excellent agreement with recent high resolution X-ray diffraction measurements of a-Si, but were found to differ in regards the ion dose dependent structure of another Group IV semiconductor: a-Ge. Specifically, no ion dose dependence of the a-Si structural parameters were observed. (C) 2002 Elsevier Science B.V. All rights reserved.
12.	Hansson, Hans Christen, et al. (author) Long range aerosol transport in Southern Sweden : An example of multtvariate statistical evaluation methodology 1984 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 3:1-3, s. 483-488 Journal article (peer-reviewed)abstract The utilization of multivariate statistical techniques is discussed with emphasis on the rather new method SIMCA, when applied to multielemental data. The procedures of scaling and normalizing are described. The data base used is from a project studying long range aerosol transport to southern Sweden. SIMCA reveals low variability in fine mode elemental composition in southerly air masses being clearly different from the elemental compositions found in northerly air masses.
13.	Hansson, H. C., et al. (author) PIXE in complex analytical systems for atmospheric chemistry 1987 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 22:1-3, s. 235-240 Journal article (peer-reviewed)abstract A schematic mechanistic box model presenting processes in atmospheric chemical cycles is used to present the main research objectives. From this the main use of PIXE within atmospheric chemistry is discussed. An analytic system giving molecular composition is necessary to fully understand and quantify the chemical and physical pathways described in the model for different compounds. Combining PIXE with complementary techniques can enhance knowledge of molecular composition. Therefore, techniques which are complementary to PIXE that give such important parameters as mass, soot, and major ions are discussed. Difficulties in efficiently combining and using the discussed analytical techniques in practice are recognized. The sampling substrates and sampling methods used are discussed and evaluated from this point of view. The use of thin Al foil as substrate and an electrostatic precipitator for aerosol sampling is suggested as one solution. The importance of developing methods for use of this analytical system of the different phases present in the atmosphere is stressed.
14.	Huang, M, et al. (author) The continuing saga of the Si-like intercombination lines in highly charged ions, Si-like rhodium 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 205, s. 119-122 Journal article (peer-reviewed)abstract The 3s(2)3p(2 3)P(1.2)-3s3p(3) S-5(2) intercombination lines for Si-like Rh have been investigated using the techniques of beam-foil spectroscopy. Two lines have been identified as belonging to these transitions having, however, different wavelengths from what would be expected based on published iso-electronic trends. The identifications suggested here are strengthened by requirements on (a) the known fine structure splitting in the ground configuration, (b) an intensity ratio based on branching ratios, (c) similar decay characteristics and (d) expected behaviour of the lines as a function of the ion beam energy. (C) 2003 Elsevier Science B.V. All rights reserved.
15.	Hutton, Roger, et al. (author) EBIT spectroscopy of Pm-like tungsten 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 205, s. 114-118 Journal article (peer-reviewed)abstract Methods of VUV electron beam ion trap (EBIT) spectroscopy are applied to the study of Pm-like tungsten (W13+). These data show that theory appears well capable of dealing with these multi-electron (61) ions, at least for high ionization stages. A comparison of other spectroscopic methods applied to the study of other ions of the Pm I sequence is also given, and finally a search for the Pm-like W lines at the ASDEX Upgrade Tokamak is mentioned. (C) 2003 Elsevier Science B.V. All rights reserved.
16.	Kester, O., et al. (author) Accelerated radioactive beams from REX-ISOLDE 2003 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 204, s. 20-20 Conference paper (peer-reviewed)abstract In 2001 the linear accelerator of the Radioactive beam EXperiment (REX-ISOLDE) delivered for the first time accelerated radioactive ion beams, at a beam energy of 2 MeV/u. REX-ISOLDE uses the method of charge-state breeding, in order to enhance the charge state of the ions before injection into the LINAC. Radioactive singly-charged ions from the on-line mass separator ISOLDE are first accumulated in a Penning trap, then charge bred to an A/q
17.	Kristiansson, Per, et al. (author) Photon-tagged nuclear reaction analysis for trace element determination 1997 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 132:1, s. 159-176 Journal article (peer-reviewed)abstract The new trace element measurement technique "photon-tagged Nuclear Reaction Analysis" (pNRA) is introduced and the experimental procedures are described in detail. The pNRA-technique is an ion-beam analytical technique intended for the determination of the abundance of the lightest elements, ranging from lithium to phosphorus. The technique is a complement to the PIXE technique. pNRA is a multiparameter technique, using fast coincidence criteria and high time resolution which identifies and measures the products of nuclear reactions from which the amount of an element in the irradiated target can be determined. A detection system suitable for use in pNRA analysis is described. Different aspects of experimental parameters, e.g. time resolution and γ-efficiency, are discussed and evaluated. Yield curves for all relevant light isotopes are presented for a proton beam energy between 3.5 and 3.75 MeV, and minimum detection limits (MDLs) are extracted for different environments. The results of the MDL measurements with pNRA_ are compared with the detection limits of other frequently used techniques such as proton-induced γ-emission (PIGE) and particle elastic scattering analysis (PESA), and are shown to match these other techniques very well.
18.	Kugler, E., et al. (author) The New Cern-Isolde Online Mass-Separator Facility at the Ps-Booster 1992 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 70:1-4, s. 41-49 Journal article (peer-reviewed)abstract The ISOLDE on-line isotope separators have been operated since 1967 at the CERN-SC. This 600 MeV proton synchro-cyclotron had to be shut down in December 1990 after 33 years of service and it was decided to move ISOLDE to a new experimental area. The new on-line mass-separator facility is now under construction at the CERN PS-Booster. This accelerator provides an average current of about 2-mu-A of 1 GeV protons in very short high intensity pulses at low repetition rate. The beam can hit either one of the two target stations, the general purpose separator (GPS), a reconstructed ISOLDE-2 type machine (which can deliver beams simultaneously into three beam lines), and the high resolution separator (HRS), which is essentially the slightly modified ISOLDE-3 separator. The central GPS beam line and the HRS feed a common beam transport system to which most of the experiments will be connected. The new facility will be taken into operation in spring 1992.
19.	Kvick, Åke (author) Materials science at the European Synchrotron Radiation Facility. 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 199, s. 531-535 Journal article (peer-reviewed)abstract The Materials Science Beamline ID11 at the European Synchrotron Radiation Facility in Grenoble, France is dedicated to research in materials science notably employing diffraction and scattering techniques. Either an in-vacuum undulator with a minimum gap of 5 mm or a 10 kW wiggler giving high-flux monochromatic X-rays generates the synchrotron radiation in the energy range 5–100 keV. The dominant research is in the area of time-resolved diffraction, powder diffraction, stress/strain studies of bulk material, 3D mapping of grains and grain interfaces with a measuring gauge down ~5×5×50 m, and microcrystal diffraction. A variety of CCD detectors are used to give time-resolution down to the millisecond time regime.
20.	Larsson, N. P.O., et al. (author) Characterization of the response function of a Si(Li) detector using an absorber technique 1989 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 43:4, s. 574-580 Journal article (peer-reviewed)abstract The non-Gaussian response function of a Si(Li) detector has been measured for characteristic Kα X-rays in the energy interval 1.5-8.6 keV using an absorber technique. The method is based on the different response to an attenuating absorber placed in front of the detector for the detector tail as compared to fully absorbed photons in the same position in the spectrum. The shape of the tail of a Kα X-ray peak could be derived from three X-ray spectra acquired with different attenuating absorbers using the PIXE or XRF method for excitation of single element standards. The line shape function could be described by a full energy Gaussian, a shelf, an exponential and a Si-escape component. The results presented are in good agreement with previously reported response functions obtained in measurements of monochromatic X-rays. The results will be implemented in a computer program for evaluating micro-PIXE spectra.
21.	Li, Hong-Kou, et al. (author) A PIXE System for Routine Longitudinal Scanning of Single Hair Strands 1984 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 3:1-3, s. 347-351 Journal article (peer-reviewed)abstract This article describes a PIXE system designed and constructed for routine longitudinal scanning of single hair strands. In constructing a PIXE system for trace elemental scans of single hair strands on a routine basis, a fairly intense beam has to be used but the heating damage must be kept to a minimum. The experimental conditions (charge integration, beam homogeneity etc.) have to be carefully controlled in order to give accurate PIXE results. The geometrical thickness of the hair at each point of the scan has to be determined and a qualitative knowledge of the elemental distribution over the cross section of the hair has to be provided for a proper interpretation of the PIXE results. In the present PIXE system the geometrical thickness of a hair strand at each point along the scan is determined by counting the number of backscattered protons simultaneously with the PIXE analysis, and a qualitative knowledge of the elemental distribution over the cross section of the hair is obtained through bombarding the hair at particular points with different proton energies.
22.	Li, Hong-Kou, et al. (author) A Quantative Basis for Hair Analysis Using PIXE 1985 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 12:2, s. 248-256 Journal article (peer-reviewed)abstract The PIXE technique offers the possibility of scanning a single hair strand longitudinally with a millimetre proton beam for trace elements. However, the accuracy of the method has been questioned since the quantification of the mass concentration has been a serious problem. In this paper a specific beam-hair-detector geometry is assumed, and the correction factor accounting for the proton energy loss and the X-ray absorption in a regular hair is calculated. 43 hair segments from 8 individuals, ranging from 45 to 110 μm in in diameter were analyzed giving a mean value of 4.32% (standard deviation 0.25%) for sulphur, and a mean value of 149 ppm (standard deviation 35 ppm) for zinc. It is shown that the correction is important not only for the determination of the absolute elemental concentrations but also for the determination of their relative longitudinal distributions. The secondary corrections accounting for the inhomogeneous elemental distribution over the cross section and the irregular shape and/or the differing mass density of a hair are also calculated. It is concluded that the accuracy and precision of the PIXE method does not become considerably lower when it is applied to single hair strands, and accuracy and precision below 10% may be reached by implementing the procedure described.
23.	Li, Hong-Kou, et al. (author) Rutherford Backscattering - A Tool for Quantification of the Results of PIXE Analysis of Single Hair Strands 1985 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 12:2, s. 265-268 Journal article (peer-reviewed)abstract As shown in a companion paper the geometrical diameter of a hair strand is an important parameter for quantification of its trace element content after PIXE analysis. By analysing Rutherford backscattered protons simultaneously with PIXE analysis a reliable estimate of the hair diameter can be obtained. In this work the hypothesis that there exists a linearity between the geometrical diameter and the number of backscattered protons in a certain energy interval is developed, discussed and experimentally verified.
24.	Lindstrom, J.L., et al. (author) Defect engineering in Czochralski silicon by electron irradiation at different temperatures 2002 In: Nuclear Instruments and Methods in Physics Research Section B. - 0168-583X .- 1872-9584. ; 186:1-4, s. 121-125 Journal article (peer-reviewed)abstract Infrared absorption studies of defect formation in Czochralski silicon irradiated with fast electrons in a wide range of temperatures (80-900 K) have been performed. The samples with different contents of oxygen (16O,18O) and carbon (12C,13C) isotopes were investigated. The main defect reactions are found to depend strongly on irradiation temperature and dose, as well as on impurity content and pre-history of the samples. Some new radiation-induced defects are revealed after irradiation at elevated temperatures as well as after a two-step (hot+room-temperature (RT)) irradiation. © 2002 Elsevier Science B.V. All rights reserved.
25.	Lushchik, A, et al. (author) Nano-scale radiation effects in wide-gap crystals under irradiation by VUV photons 2002 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 191:1-4, s. 135-143 Journal article (peer-reviewed)abstract The creation spectra of F centres by synchrotron radiation of 5-35 eV have been measured for Na6Al6Si6O24(NaI)(2x) and Na6Al6Si6O24(NaBr)(2x) optical ceramics at 8 and 80 K. The exciting photons cause the excitation and ionization of halogen ions (6-8 eV) and of an aluminosilicate carcass (8.5-31 eV) or the excitation of Na+ ions (32-35 eV). An exciting photon of 20-26 and 27-31 eV creates two or three electron-hole pairs, respectively. Besides the electron-hole creation mechanism of F centres with the participation of pre-irradiation defects, the basic interstitial-vacancy creation mechanism of Frenkel defect pairs is realized in socialites at high doses of irradiation at 300 K. A Br-0 atom formed at the irradiation in a regular beta-cage can penetrate into a neighbouring cage. As a result, an F centre and a Br-2(-) molecule (H centre) are formed and the interdefect distance in this pair is about I nm. The efficiency of F-H pair creation is especially high under the conditions of multiplication of electron-hole pairs. In contrast to alkali halides the crowdion configuration of interstitials does not exist in sodalites and F-H pairs are stable up to 450 K.
26.	Malmqvist, K. G., et al. (author) PIXE and proton microprobe advances at the Lund Institute of Technology 1989 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 40-41:PART 1, s. 685-689 Journal article (peer-reviewed)abstract A review of recent advances in high-energy ion beam analysis at the Lund Institute of Technology is presented. A nonvacuum specimen chamber allows chemical speciation using a combination of ion beam analysis and controlled heating. The development of a new versatile scanning proton microbeam based on a new dedicated accelerator, an achromatic triplet lens and an advanced specimen chamber is outlined together with the performance of a microVAX-II/VMEbus-based data acquisition system.
27.	Malmqvist, Klas, et al. (author) Proton and Electron Microprobe Analysis of Human Skin 1984 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 3:1-3, s. 611-617 Journal article (peer-reviewed)abstract In order to demonstrate the feasibility of the proton microprobe in the analysis of dermatological material when a spatial resolution of a few micrometres is sufficient and to compare it with the electron microprobe technique, duplicate sections of human skin have been analysed with both methods. A skin sample was obtained from each of three healthy volunteers. After cryosectioning (12 μm) and freeze-drying adjacent sections of each sample were scanned by the electron microprobe and the proton microprobe, respectively.
28.	Martinsson, Bengt G., et al. (author) A high-sensitivity method for hydrogen analysis in thin targets 1993 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 82:4, s. 589-599 Journal article (peer-reviewed)abstract A sensitive and fast method for hydrogen analysis has been developed. The method is based on a technique where a proton beam of a few MeV impinges on the target and the elastically scattered proton and the recoiling target hydrogen nucleus are detected in coincidence. The method makes use of the difference in time of flight and requires no energy determination. The system consists of two thin, large-area plastic scintillation detectors placed at angles of 45° relative to the beam direction on either side of the beam. Evaluations of the system showed that a stable coincidence yield with respect to position in the target plane and target displacement can be obtained provided that the geometry of the setup is carefully designed. The yield as a function of target thickness was almost linear for target thicknesses up to 2000 μg/cm2. It was also found that count rates up to 500000 s-1 in each branch may be used. The minimum detection limit for the hydrogen detection system was found to be of the order of a few pg/cm2 for a proton beam energy of 3.6 MeV.
29.	Martinsson, Bengt G. (author) An external beam PIXE/PESA setup for characterization of fine aerosols 1987 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 22:1-3, s. 356-363 Journal article (peer-reviewed)abstract An external beam setup has been developed for the determination of elemental concentrations in fine aerosols (aerodynamic particle diameter less than about 2 μm). Carbon, nitrogen and oxygen are determined with particle elastic scattering analysis (PESA) and, simultaneously, elements heavier than silicon with PIXE at a proton energy of 3.58 MeV. Earlier work on aerosols with PESA and most PIXE work have been performed with the aerosol sample in high vacuum, which causes losses of certain compounds, e.g. several organic substances present in atmospheric aerosols. These losses are increased by the heating effect of the beam. The rate of mass loss of different aliphatic hydrocarbons has been investigated for different chamber gas pressures, chamber gas exchange rates and beam current densities. The external beam approach showed a considerable improvement compared with high vacuum analysis. The external beam setup is described in some detail with respect to geometry, electronics and the chamber gas-handling system.
30.	Martinsson, Bengt G., et al. (author) Experimental cross sections for Bremsstrahlung production by the impact of MeV protons on low-Z targets 1990 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 47:4, s. 361-369 Journal article (peer-reviewed)abstract The production of continuously distributed X-rays by the impact of protons of 1.9-3.0 MeV for X-ray energies between 4 and 6.5 keV, and 1.9-2.65 MeV for X-ray energies between 1.7 and 4 keV has been investigated. Five different target types have been irradiated: polyethylene, polystyrene, carbon. KaptonTM and MylarTM. The results are presented as absolute cross sections for continuous X-ray production at the proton energy 2.55 MeV, and the proton energy dependence is presented in terms of linear and exponential functions in different regimes related to electron binding energy. The effect of electron escape was investigated. The data were modelled using the concept of effective electron escape depth.
31.	Martinsson, Bengt G. (author) Investigation of particle elastic scattering analysis as a complementary technique to pixe for aerosol characterization 1986 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 15:1-6, s. 636-642 Journal article (peer-reviewed)abstract The possibility of analysis by the detection of elastically scattered particles for carbon, nitrogen, oxygen and also hydrogen determination in the fine mode of aerosols has been investigated. The main objectives in this study have been to find suitable projectiles (protons or alpha particles) and projectile energy, in order to obtain separated peaks for the elements of interest and to achieve high analytical sensitivity and precision. Sensitive PIXE analysis should also be obtained on an aerosol substrate suitable for both methods. Relative scattering cross sections at an angle of 170° for protons (3.5-5.8 MeV) and alpha particles (8-9 MeV) on 12C, 14N and 16O have been investigated. Lower and upper energy limits are set by the demand for resolved peaks from C, N and O and the accelerator available, respectively. Protons were found to be the most suitable projectiles and for one proton energy, 3.58 MeV, fulfilling the requirements mentioned above, the possibility for H determination at laboratory scattering angles between 29° and 59° has been investigated. Some aerosol filters and foils have also been investigated at this proton energy in order to find a suitable aerosol substrate. The lowest detection limits were obtained for thin aluminum foils, yielding 15, 10 and 350 ng cm-2 for C, N and O, respectively, and PIXE detection limits comparable to those obtained with a Nuclepore® filter.
32.	Martinsson, Bengt G., et al. (author) Ion beam thermography - analysis of chemical compounds using ion beam techniques 1988 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 34:2, s. 203-208 Journal article (peer-reviewed)abstract The analytical technique of ion beam thermography (IBT) is reported for the first time. IBT is a technique for the determination of chemical compounds. This IBT setup combines the multielemental ion beam technique's particle-induced X-ray emission (PIXE) and particle elastic scattering analysis (PESA) with thermography. A large number of elements are monitored with PIXE (Z > 14) and PESA (hydrogen, carbon, nitrogen and oxygen). The thermographie treatment results in a thermogram for each element. The chemical compounds are inferred from these thermograms. This work describes the experimental setup. The capability of IBT is demonstrated on NH4C1, NH4NO3 and (NH4)2SO4.
33.	Mentes, Besim, et al. (author) Chemical speciation of aerosol samples by ion beam thermography 1996 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 109-110, s. 511-518 Journal article (peer-reviewed)abstract Ion beam thermography (IBT) is a technique for the determination of chemical compounds. The IBT setup combines the multielemental ion beam techniques PIXE, PESA, pNRA and cPESA with thermography. During thermography the temperature is gradually increased up to the order of 600 °C, causing vaporisation of chemical compounds at specific temperatures. The combination of methods display low detection limits over practically the whole periodic table, i.e. PIXE: Z > 13, PESA: C, N, O, pNRA: Li, Be, B, F, Na, Mg, cPESA: H. The analysis is undertaken with an external beam. The thermographic treatment results in a thermogram for each element i.e. the concentration as a function of the temperature of the sample. The chemical compounds are identified by the vaporisation temperature and the stoichiometric relations between the elements vaporised at that temperature. This work deals with technical improvements of the setup and evaluates the dependence on the rate of temperature increase of the vaporisation temperature of chemical compounds. An atmospheric aerosol sample was analysed to demonstrate the capabilities of this combination of IBA methods in atmospheric aerosol research. All major and several minor elements of the sample could be determined, the major inorganic compounds could be speciated and the carbonaceous constituents could be classified according to volatility.
34.	Mentes, B., et al. (author) Ion-beam thermography analysis of the H2SO4-(NH4)2SO4 system in aerosol samples 2000 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 168:4, s. 533-542 Journal article (peer-reviewed)abstract Ion-beam thermography (IBT) is used to determine the chemical composition of atmospheric aerosols. The aerosols are analyZed by a combination of four ion-beam techniques PIXE, PESA, pNRA and cPESA during thermography. These techniques monitor the concentrations of the available elements during the stepwise heating of the sample. For each element a thermogram, i.e., the concentration vs. temperature, is obtained. Vaporization of chemical compounds generated during heating will result in a decrease in concentration in the thermograms at temperatures that are characteristic for the compounds. The compounds are identified by the stoichiometric ratios and the characteristic vaporization temperatures (CVT). This paper deals with the analysis of five different laboratory-produced aerosols with the following compositions: (NH4)2SO4, (NH4)1.5H0.5SO4, NH4HSO4, (NH4)0.5H1.5SO4 and H2SO4. All compounds were readily separated with respect to response in IBT analysis and the amount of water bound to the two most acidic compounds could be quantified.
35.	Mentes, B., et al. (author) Vaporisation characteristics and detection limits of ion beam thermography 1999 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 150:1-4, s. 136-143 Journal article (peer-reviewed)abstract Analytical properties of the chemical speciation method, Ion beam thermography (IBT), have been investigated. IBT combines the multi-elemental ion beam techniques PIXE, PESA, pNRA and cPESA with thermography. During thermography the sample temperature is gradually increased, causing vaporisation of chemical compounds at specific temperatures and the sample at the same time undergoes analysis by the above-mentioned techniques. The characteristic vaporisation temperature (CVT) and the stoichiometric relations between the elements vaporised at that temperature, identify the chemical compounds. This work describes the reproducibility of the method, the dependence of the rate of temperature increase, the dependence of the sample thickness and the influence from aerosol particle size on the CVT. In addition the minimum detectable mass changes for IBT analysis of marine and continental aerosols were estimated by calculation for major and minor elements.
36.	Morishita, Y, et al. (author) Visible light spectroscopy of Ar6+ ions in high Rydberg states produced with a microcapillary target 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 205, s. 758-761 Journal article (peer-reviewed)abstract We have observed photons in the visible light range emitted from slow (2.0 keV/amu) highly charged Ar6+ ions which have captured one electron and transmitted through a Ni microcapillary target. Observed lines were identified by comparing with an ab initio calculation based on the multi-configuration Hartree-Fock method. (C) 2003 Elsevier Science B.V. All rights reserved.
37.	Olabanji, Simon O., et al. (author) Inner-shell ionization processes in low Z (Z ≤ 20) elements by proton bombardment 1987 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 24-25:PART 1, s. 81-84 Journal article (peer-reviewed)abstract K-shell X-ray ionization cross section from thin targets of P, S, Cl, K and Ca by proton impact in the energy range of 1.0-5.0 MeV are reported using a Si(Li) detector. Our experimental results are compared with previous very scanty available data and with ECPSSR theory. Data for P are reported for the first time. Results for S, Cl and K in this wide energy range are also new data. Our results show very good agreement with those of other authors and ECPSSR theory.
38.	Papaspiropoulos, G., et al. (author) High sensitivity elemental analysis methodology for upper tropospheric aerosol 1999 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 150:1-4, s. 356-362 Journal article (peer-reviewed)abstract In this study, a sampling and analysis tool for aerosol particles has been developed. Its purpose is to characterize upper tropospheric aerosols, where concentrations are low. Since measurements will be made from an airplane, a time resolution of one hour is desirable. These conditions require efficient sampling and analysis with low detection limits. To accomplish this, our sampler uses impaction, concentrating the aerosol deposit on a small area. The impactor has 14 parallel sampling lines which are used sequentially to achieve the time resolution. The elemental analysis is done with Particle-Induced X-ray Emission (PIXE), profiting from its high absolute sensitivity. The aerosol is expected to contains primarily sulphur (S) and emphasis is placed on this element, however the multi-elemental nature of PIXE is of course used. Several substrates have been investigated regarding minimum detection limits. Scanning Transmission Ion Macroscopy (STIM) analysis has been conducted on two outdoor aerosol samples, rendering three-dimensional images and mass distribution profiles. The setup was tested at ground level with high time resolution (5 min). Results show that the detection capabilities are excellent.
39.	Persson, Per, et al. (author) Determination of the detection limit of Ni-59 at the Lund AMS facility by using characteristic projectile X-rays 2000 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 160:4, s. 510-514 Journal article (peer-reviewed)abstract Accelerator mass spectrometry (AMS) is an ultra-sensitive method for counting atoms, both radionuclides and stable nuclides. When using small tandem accelerators to measure heavy isotopes, interfering isobars are often troublesome. One way to reduce this interference is to combine AMS with the detection of characteristic X-rays of the projectile. After analysis in the AMS system it is possible to identify ions of different atomic number by their characteristic X-rays, by slowing down the ions in a suitable target. In this paper, the detection limit of Ni-59 at the Land AMS facility is reported. A method for the chemical extraction of nickel from stainless steel, combined with a purification step to reduce the cobalt content in the sample by several orders of magnitude, is also described. (C) 2000 Elsevier Science B.V. All rights reserved.
40.	Removic-Langer, K, et al. (author) Spin and orbital moments in Au/Co/Au(111)/W(110) across the spin-reorientation transition-temperature 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 200, s. 210-214 Journal article (peer-reviewed)abstract The temperature-driven spin-reorientation transition (SRT) has been investigated in a layer of 2.1 nm Co in Au/Co/Au. We studied the evolution and stability of the in-plane magnetization components in the temperature range from 300 to 90 K by means of polarized neutron reflectometry (PNR) and Co L-edge X-ray magnetic circular dichroism (XMCD) measurements. The PNR measurement provides evidence for the occurrence of a SRT in this temperature range. XMCD can be used as a vector magnetometer that yields both the in- and out-of-plane magnetization components per Co atom. Combining the results of both techniques (PNR and XMCD) allows separating the orbital and spin magnetic moments using magneto-optical sum rules. We observed that already above the SRT the in-plane orbital moment component changes significantly stronger than the spin component. (C) 2002 Elsevier Science B.V. All rights reserved.
41.	Ridgway, MC, et al. (author) Common structure in amorphised compound semiconductors 2003 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 199, s. 235-239 Journal article (peer-reviewed)abstract Extended X-ray absorption fine structure has been utilised to determine the structural parameters of the amorphous III-V semiconductors GaP, GaAs, InP and InAs. The amorphous phase was formed by ion implantation to inhibit preparation-specific artefacts associated with the alternative fabrication techniques of sputtering and evaporation. Relative to crystalline standards, increases in bond length and Debye-Waller factor were apparent for all materials with a slight reduction in coordination number (3.8-4 atoms). Similarly, homopolar bonding in the amorphous phase was measurable for all materials. For example, In-In bonding in amorphous InP comprised similar to18% of the total In bonds and demonstrated the necessity of a ring distribution containing both even and odd members. (C) 2002 Elsevier Science B.V. All rights reserved.
42.	Shariff, Asad, et al. (author) Calibration of a new chamber using GUPIX software package for PIXE analysis 2002 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 189:1-4, s. 131-137 Journal article (peer-reviewed)abstract 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.
43.	Swietlicki, Erik, et al. (author) PIXE Detection Limits for some Aerosol Collection Substrates by Excitation with protons and 4He2+ Ions from a 3 MV Tandem Accelerator 1984 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; :1084, s. 441-445 Journal article (peer-reviewed)abstract Comparisons of PIXE detection limits for K, X rays using 2-5 MeV protons and 7-8 MeV 4He2+ ions as projectiles have been performed. The comparisons have been made for common aerosol backings. According to simple theoretical considerations regarding X-ray production cross sections and the production of background radiation, detection limits for 4He2+ should be two to four times lower than for protons for equal vefoeity projectiles of equal numbers. However, the background in X-ray spectra arising from gamma-quanta being Compton scattered in the Si(Li) detector can strongIy affect the detection limits. The detection limits using protons and 4HeZ+ ions from a 3 MV electrostatic tandem accelerator are determined and discussed.
44.	Swietlicki, Erik, et al. (author) PIXE elemental characterization of air masses using a multivariate statistical technique 1987 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 22:1-3, s. 264-269 Journal article (peer-reviewed)abstract An example is given to show the possibility of using a multivariate statistical evaluation technique in order to extract more information from a multielemental PIXE data set. Four weeks of continuous sampling was carried out at a background air pollution monitoring station in Sweden. Samples were collected both in fine and coarse mode, with a cutoff at 2 μm. In the subsequent PIXE analysis of the samples, 12-16 elements were detected in the fine fraction and 9-12 elements in the coarse fraction. The fine fraction PIXE data was further analysed using the multivariate statistical programme package SIMCA, which combines a pattern recognition technique and principal component analysis. Based on 1000 mbar back trajectories for the sampling period, principal component class models were constructed for Easterly and North-Westerly air masses using 15 elements (S, K, Ca, Ti, V. Cr, Mn, Fe, Ni, Cu, Zn, Ga. As, Br and Pb). For these elements, mean concentration values and standard deviations for the two classes are given. A methodology is presented which excluded outliers and facilitated the calculation of classes with a restricted and definable data distribution representative of the elemental composition of the air masses originating from the two source regions.
45.	Swietlicki, E., et al. (author) The use of PIXE and complementary ion beam analytical techniques for studies of atmospheric aerosols 1996 In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 109-110, s. 385-394 Journal article (peer-reviewed)abstract PIXE is nowadays a routine analytical technique in the study of atmospheric aerosols. If it aspires to continue to be so in the future, it will have to compete with a range of other powerful analytical techniques, and outperform them in some respect. It will be shown how PIXE can indeed play an important role in future studies of atmospheric aerosols. For clarification, two concrete examples will be discussed in some detail, involving PIXE either as the sole analytical technique or used in combination with various other ion beam analytical techniques for an almost complete characterisation of the atmospheric aerosol.
46.	Timmers, H, et al. (author) Threshold stoichiometry for beam induced nitrogen depletion of SiN 2002 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 190, s. 428-432 Journal article (peer-reviewed)abstract Measurements of the stoichiometry of silicon nitride films as a function of the number of incident ions using heavy ion elastic recoil detection (ERD) show that beam-induced nitrogen depletion depends on the projectile species. the beam energy, and the initial stoichiometry. A threshold stoichiometry exists in the range 1.3 > N/Si greater than or equal to 1, below which the films are stable against nitrogen depletion. Above this threshold, depletion is essentially linear with incident fluence. The depletion rate correlates non-linearly with the electronic energy loss of the projectile ion in the film. Sufficiently long exposure of nitrogen-rich films renders the mechanism, which prevents depletion of nitrogen-poor films, ineffective. Compromising depth-resolution. nitrogen depletion from SiN films during ERD analysis can be reduced significantly by using projectile beams with low atomic numbers. (C) 2002 Published by Elsevier Science B.V.
47.	Westerlind, M., et al. (author) Lifetimes of 2p53p and 3d levels in Ne-like chlorine, Cl VIII 1988 In: Nuclear Inst. and Methods in Physics Research, B. - 0168-583X. ; 31:1-2, s. 300-304 Journal article (peer-reviewed)abstract Experimental lifetimes of seven 2p53p and six 2p53d levels in Ne-like chlorine, Cl VIII, have been measured using the beam-foil technique. For the first time in the Ne-sequence, the ANDC method of cascade correction has been applied in the lifetime determination of the 3p levels. This procedure lowered the values by 10 to 30% compared to the results from multiexponential curve-fitting. For all levels studied, except 3p3D2 and 3D1, the experimental lifetimes are in good agreement with recent theoretical values. A comparison between experimental and theoretical lifetimes for some 3p and 3d levels along the isoelectronic sequence is presented.
48.	Whitlow, Harry J, et al. (author) Fundamental effects and non-linear Si detector response 2002 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 190:1-4, s. 375-378 Journal article (peer-reviewed)abstract Non-linearity in the energy response of a Si p-i-n charged particle detector has been studied for incident particles with Z(1) between 3 and 26, and energies between 0.1 and 0.7 MeV per nucleon. Although the data closely followed a straight line relations, fitting of the data to a third order polynomial revealed that the response exhibited a persistent curvature that acted to reduce the energy interval spanned by a channel as the energy increased. The curvature increased as Z(1) increased from 4 to 8 and then systematically decreased. The curvature is larger and has the opposite energy dependence to the stopping in a dead entrance window and the energy deposited in non-ionising processes within the active layer. The plasma recombination dependence on the average stopping along the plasma column may account for the reduction in curvature as Z(1) increases from 9 to 25 but cannot explain the net effect. The low-energy increase in energy channel span, which has also been reported by others, might be associated with electron excitation in resonant and direct classical quasi-elastic collisions for low-energy ions, or less likely, electronic non-linearity's associated with Z(1) and energy dependent time structure in the current pulse from the detector. Simple interpolation of the window-loss corrected polynomial coefficients is the best approach if the calibration for Z(1) cannot be established directly.
49.	Whitlow, Harry J, et al. (author) Measurement and uncertainties of energy loss in silicon over a wide Z(1) range using time of flight detector telescopes 2002 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 195:1-2, s. 133-146 Journal article (peer-reviewed)abstract The energy loss of projectiles with Z(1) in the range 3-26 has been experimentally measured in the 0.1-0.7 MeV per nucleon energy range in the same Si stopping foil of 105.5 mug cm(-2) thickness using a time of flight-energy (ToF-E) elastic recoil detection analysis (ERDA) setup. A detailed study of the experimental uncertainties for ToF-E and ToF-ToF-E configuration has been made. For ERDA configurations where the energy calibration is taken against the edge positions small uncertainties in the angle at which recoils are detected can introduce significant, absolute uncertainty. The relative uncertainty contribution is dominated by the energy calibration of the Si E detector for the ToF-E configuration and the position of the second ToF detector in ToF-ToF-E measurements. The much smaller calibration uncertainty for ToF-ToF-E configuration implies this technique is superior to ToF-E measurements with Si E detectors. At low energies the effect of charge changing in the time detector foils can become important. It was found that empirical stopping numbers which include the effect of effective-charge were more closely clustered about a trend line when plotted against the Bohr parameter than the corresponding Bethe parameter. Study of the deviations from the trend line showed evidence of a shell dependant effect that exceeded the anticipated maximum relative uncertainties.
50.	Whitlow, Harry J, et al. (author) Measurements of Si ion stopping in amorphous silicon 2002 In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 190:1-4, s. 84-88 Journal article (peer-reviewed)abstract The stopping of Si-28 ions in polycrystalline Si foils has been measured over the energy range 0.1-3.3 MeV per nucleon. For the low energy interval (0.1-0.5 MeV per nucleon), time of flight-energy elastic recoil detection analysis method was used, whilst for the high energy region (1.2-3.3 MeV per nucleon) the energy loss in the same foil was measured using a Si p-i-n diode with the Si-28 ions directly incident on the foil following acceleration. Below the stopping maximum the results are in good agreement with literature data based on Doppler shift measurements of short nuclear lifetimes but are about 20%, smaller than the SRIM prediction. Above the stopping maximum the data are in agreement with SRIM within the limits of statistical uncertainty.

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