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Differential cross section of X-ray production induced by O, Cl, Cu and Br ions with energies between 4 MeV and 40 MeV have been measured for thin targets of Ti, Fe, Zn, Nb and Ta in a direct way . A fully characterized silicon drift diode was used as X-rays detector. Beam currents have been measured by a system of two Faraday cups. Corrections for target thickness effects have been applied to the raw data. Experimental cross sections are compared both with theory and with previously published results. Experimental results from other authors are in reasonable agreement with ours over a wide energy range. Theory produces consistent results in the case of oxygen ions but gives cross sections even orders of magnitude below the experimental ones for heavier ions (ECPSSR-UA) or contrasting results (PWBA) depending on the ion-target combination. [ABSTRACT FROM AUTHOR]

The first results on betatron radiation obtained in laser-plasma acceleration experiments at the FLAME laser facility are presented. The diagnostic apparatus for the X-ray detection available at the facility is described together with the experimental setup for the generation of betatron radiation. [ABSTRACT FROM AUTHOR]

A multipurpose facility for low cross section measurements has been developed at Inter University Accelerator Centre, New Delhi, India. The facility consists of a multipurpose miniature chamber equipped with 1 m focal length normal incidence Monochromator and charge coupled device based detection system which has been aligned to realize the best resolution of the spectrometer. The chamber in this facility collects radiation 100 times more efficiently from the older system, without using any extra focusing mirror assembly. It is ensured to have the provision of mounting an X-ray detector and the spectrometer transverse to the beam direction simultaneously in the same chamber. The atomic spectroscopic studies can be performed by interaction of ions beams with both thin foil and gas targets. Provision for using photomultiplier tube instead of charge coupled device, is employed in the system depending on the condition of the source strength or other detection issues. We observed the essence of a very weak atomic phenomenon, a triply excited autoionizing forbidden transition, using the above facility to demonstrate its capability for measuring such low cross section phenomena. The present developed facility covers a large spectroscopic region from X-rays to the near infrared (0.1–10,000 Å). [ABSTRACT FROM AUTHOR]

The X-ray emissions induced by argon ions for the elements from Mg to Bi were measured on mono-elemental thin films. K-, L- and M-shells X-ray production cross section were obtained for the 40 Ar projectile energies of 32, 40, 48, 56 and 64 MeV, considering absorption corrections. For the most of target elements the approach used is based on the calculation of X-ray production cross sections through the cross section of Rutherford backscattering. The efficiency of the X-ray detector was determined using standard calibrated radioactive sources. The experimental results are compared to the predictions of the ECPSSR and PWBA theories calculated with the ISICS code. [ABSTRACT FROM AUTHOR]

X- and γ -ray detection is currently a hot topic for a wide scientific community, spanning from astrophysics to nuclear medicine. However, lack of optics capable of focusing photons of energies in the energy range 0.1–1 MeV leaves the photon detection to a direct-view approach, resulting in a limited efficiency and resolution. The main scope of the INFN-LOGOS project is the development of technologies that enable manufacturing highly performing optical elements to be employed in the realization of hard X-ray lenses. Such lenses, typically named Laue lenses, consist of an ensemble of crystals disposed in concentric rings in order to diffract the incident radiation towards the focus of the lens, where a detector is placed. In particular, the INFN-LOGOS project aims at the realization of intrinsically bent silicon and germanium crystals exploiting the quasi-mosaic effect for focusing hard X-rays. Crystal manufacturing relies on a proper revisitation of techniques typically employed in silicon micromachining, such as thin film deposition and patterning or ion implantation. [ABSTRACT FROM AUTHOR]

Abstract: A 1.7MeV tandem accelerator has been recently installed at Centro Atómico Bariloche, Argentina. This communication includes a brief description of the system facility with the main associated equipment, in particular that used for PIXE measurements. The X-ray detector efficiency was experimentally determined by comparing X-ray characteristic spectra with theoretical predictions. The knowledge of this parameter allows us to perform quantification without standards with good precision. We show some recent applications of PIXE in archaeology and forensic science done at our laboratory. In the archaeological field we determined elements constituent of pastes and black, white, brown and ocher pigments from Aguada Portezuelo Culture (600–900 AD). This study allowed us to infer about the presence of psilomelante mineral (a mineral with barium) as precursor of some black pigments. In the forensic field we determined trace elements that are present in seven gunpowders commonly used in Argentina. We note that any gunpowder can be distinguished by the presence of trace elements. [Copyright &y& Elsevier]

Abstract: We demonstrate the stereo-PIXE method by measurement of surface topography of the relief details on 1€ coin. Two X-ray elemental maps were simultaneously recorded by two X-ray detectors positioned at the left and the right side of the proton microbeam. The asymmetry of the yields in the pixels of the two X-ray maps occurs due to different photon attenuation on the exit travel path of the characteristic X-rays from the point of emission through the sample into the X-ray detectors. In order to calibrate the inclination angle with respect to the X-ray asymmetry, a flat inclined surface model was at first applied for the sample in which the matrix composition and the depth elemental concentration profile is known. After that, the yield asymmetry in each image pixel was transferred into corresponding local inclination angle using calculated dependence of the asymmetry on the surface inclination. Finally, the quantitative topography profile was revealed by integrating the local inclination angle over the lateral displacement of the probing beam. [Copyright &y& Elsevier]

The precision of proton microprobe measurements of Sr in otoliths by proton induced X-ray emission (PIXE) has been improved significantly by use of a large area low resolution NaI(Tl) detector. This is achieved by scanning the sample simultaneously with a high resolution Si(Li) detector to measure the main constituent Ca and to confirm the absence of other elements in the counting window used by the large area detector. In our experimental setup the count rate for Sr was improved by a factor of 30. We took advantage of this to improve precision and achieve higher sample throughput in studies of diadromous fish, i.e. those whose life cycles may include both marine and freshwater stages. [Copyright &y& Elsevier]