Proton-induced X-ray Emission Data Research Articles

X-ray attenuation around K-edge of Zr, Nb, Mo and Pd: A comparative study using proton-induced X-ray emission and 241Am gamma rays

Mass attenuation coefficients (µ/ρ) for Zr, Nb, Mo and Pd elements around their K-edges are measured at 14 energies in the range 15.744–28.564 keV using secondary excitation from thin Zr, Nb, Mo, Rh, Pd, Cd and Sn foils. The measurements were carried out at the Kα and Kβ energy values of the target elements by two techniques: (1) Proton-induced X-ray emission (PIXE) and (2) 241Am (300 mCi) source. In PIXE, 2 MeV proton-excited X-rays were detected by a Si(Li) detector. In the second case, X-rays excited by 59.54 keV photons from the targets were counted by an HPGe detector under a narrow beam good geometry set-up with sufficient shielding. The results are consistent with theoretical values derived from the XCOM package and indicate that the PIXE data have better statistical accuracy.

Main chemical ingredients of the celadon glaze from Qingliangsi kiln and Zhanggongxiang kiln

The proton induced X-ray emission (PIXE) is used to determine the chemical ingredients of seven main elements in the samples of Ru Guan porcelain glazes and Ru Civil porcelain from Qingliangsi kiln in Baofeng County and the samples of celadon glaze from Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by scatter analysis and fuzzy cluster method for determining their classification and provenance. The results show that there are obvious differences between the ingredients of glaze material of Ru Guan porcelain and Ru Civil porcelain from Qingliangsi kiln, of which the former ingredients are stable and its source is localized, and that the sources and ingredients of the glaze of Ru Guan porcelain and those of celadon glaze from Zhanggongxiang kiln are not wholly the same, of which the latter sources are much scattering.

Analysis on the source of raw material of the celadon bodies from Zhanggongxiang kiln and Qingliangsi kiln by PIXE

The proton induced X-ray emission (PIXE) is used to measure the chemical ingredients of seven main elements of each sample of celadon body from Qingliangsi kiln in Baofeng County and Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by fuzzy cluster method, and the trend cluster diagram is obtained to determine their relation of classification and provenance. The result shows that the producing area of raw material of Ru porcelain bodies is concentrated in Qingliangsi kiln, while that of celadon bodies is slightly scattered in Zhanggongxiang kiln. The raw material origin of Ru porcelain bodies from Qingliangsi kiln in Baofeng County is different from that of Zhanggongxiang kiln in Ruzhou City. The materials of Ru Guan porcelain bodies and Ru Civil porcelain bodies in Qingliangsi kiln are basically the same.

The beautiful “Trionfo d’Amore” attributed to Botticelli: a chemical characterisation by proton-induced X-ray emission and micro-Raman spectroscopy

The drawing “Trionfo d’Amore” (1480–1500) is attributed to Sandro Botticelli, the great master of the Italian Renaissance. It is included in manuscript no. 143 (Biblioteca Classense, Ravenna, Italy) containing the poems “Canzoniere” and “Trionfi” of Francesco Petrarca. Two non-destructive techniques, namely proton-induced X-ray emission (PIXE) and micro-Raman spectroscopy, have been employed in this preliminary investigation to identify all the colours in the drawing. The results of the present work, showed that ochres, with the addition of a lead based pigment, were used to obtain the brown colour, and that iron-gall ink was used to trace the drawing. PIXE data also suggests that a lead point was used in the preparation of the drawing. It was not possible to identify the Lilac pigment used, while PIXE and micro-Raman yielded contrasting results in the determination of the blue colour of the sky. These results could be explained with the hypothesis of a stratification of many colours, in which a lead based colour was deposited on top of an underlying mixture of blue pigments.

Colorants used in ancient Egyptian glassmaking: Specialized studies using PIXE spectrometry

Abstract Proton-induced X-ray emission (PIXE) spectrometry has several practical advantages over other analytical techniques currently used in the study of ancient glass. It is nondestructive, it can conveniently determine a glassmaking recipe (i.e. the primary constituents used) within a single X-ray spectrum, it has superior detection limits for the minor and trace elements that are most influential in glass coloration, and, when run in a microbeam mode (with an analysis area as small as 10−2 mm2), it can provide valuable spatial resolution in the study of individual regions of decoration on multicolored vessels and jewelry. This paper discusses the current operation of the Bartol PIXE facility, with emphasis on the use of customized selective filters which allow high-sensitive measurements for trace elements in glass matrices complicated by the presence of high levels of copper, iron and lead. PIXE data recently obtained for artifacts and manufacturing debris from the New Kingdom workshop site at El-Amarna provides a practical application of these concepts.

The initial oxidation of iron at 200� and 300� C and the effect of surface sulfur

The growth of thin (0–200 A) oxide films on iron at 200 and 300 °C has been studied as a function of time and oxygen partial pressure using proton-induced X-ray emission (PIXE) and Auger electron spectroscopy (AES). Oxidation was found to be initially retarded by sulfur which had segregated onto the iron surfaces during preoxidation annealing, but only if the iron surface contained the maximum or near-maximum sulfur coverage (ca. one-half monolayer). During and immediately following the oxygen-sulfur interaction, oxide buildup appeared to be limited by a surface reaction (adsorption, ionization, or dissociation). For most of the oxidation period, pressure-dependent logarithmic oxide growth was observed at 200°C, and pressure-independent parabolic oxide growth at 300°C. Interpretation of the data indicated that oxide growth at 200°C may be limited by quantum mechanical tunneling of electronic species through the previously formed oxide film, and oxide growth at 300°C may be limited by ionic diffusion through the previously formed oxide film. Comparison of AES and PIXE data indicated that the oxide films formed at 200°C were uniform in thickness over the surface of the metal, whereas films formed at 300°C had relatively thin areas where sulfur had remained.

Non-Linear Least Squares Analysis of Proton-Induced X-Ray Emission Data

AbstractA Fortran program for analysis of spectra obtained in proton induced x-ray emission spectroscopy is under development. The first version is working and some results are shown. The program uses a model which describes the physics involved in the analysis. The continuum is described by an exponentially decreasing function representing secondary electron induced bremsstrahlung and a constant approximating different Compton scattering processes. Absorption effects are also included. All parameters in the model are fitted simultaneously. About 100 test runs have been made with good results. The continuum was accurately fitted for each spectrum. Other advantages are reliability, speed, and the fact that the program is easily adaptable to a small computer with 16K memory.