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Ion Beam Induced Charge (IBIC) microscopy performed using highly tuned microbeams of accelerated ions with energies in the MeV range is the powerful tool for analysis of charge carrier transport properties in semiconductor devices based on semiconductor hetero-junction, metal-on-semiconductor and semiconductor-on-insulator configurations. Here we present two cases of recent applications of the IBIC microscopy in the field of medical radiation physics. The reduced-rate ion microbeams with energies in the MeV range and sub-micrometer spot-sizes have been used for the investigations of the charge collection efficiency (CCE) in sensitive volumes of segmented radiation detectors in order to measure the spatial distribution and uniformity of CCE in different polarization conditions. This information allows the determination of the charge carrier transport properties in selected substructures of a particular device and to quantify its ability to accurately determine the energy deposited by incident ionizing radiation - two fundamental requirements of any microdosimeter or detector of ionizing radiation.

We describe the recent inclusion in Geant4 of state-of-the-art proton and alpha particle shell ionisation cross sections based on the ECPSSR approach as calculated by Cohen et al., called here ANSTO ECPSSR. The new ionisation cross sections have been integrated into Geant4. We present a comparison of the fluorescence X-ray spectra generated by the ANSTO ECPSSR set of cross sections and, alternatively, the currently available sets of Geant4 PIXE cross sections. The comparisons are performed for a large set of sample materials spanning a broad range of atomic numbers. The two alternative PIXE cross sections approaches (Geant4 and ANSTO) have been compared to existing experimental measurements performed at ANSTO with gold, tantalum and cerium targets of interest for nanomedicine applications. The results show that, while the alternative approaches produce equivalent results for vacancies generated in the K and L shell, differences are evident in the case of M shell vacancies. This work represents the next step in the effort to improve the Geant4 modelling of the atomic relaxation and provide recommended approaches to the Geant4 user community. This new Geant4 development is of interest for applications spanning from life and space to environmental science.

Oxygen incorporation in MgB2 thin films during their fabrication process has a strong influence on the future properties of the films, and was studied by Elastic Recoil Detection Analysis with Heavy ions and a Time-of-flight detection. A series of MgB2 thin film samples were analyzed, including films produced in situ on Al2O3-C and Si (0 0 1) substrates (with higher T-c and lower T-c) with an "on-axis" geometry, and films produced in situ with an "off-axis" geometry. The amount of oxygen detected in these films appears to be correlated with the T-c of the films, the higher the T-c the lower the oxygen content. The superconducting properties of the examined thin films are discussed in the context of the ERDA results. (C) 2008 Elsevier B.V. All rights reserved.

Oxygen incorporation in MgB2 thin films during their fabrication process has a strong influence on the future properties of the films, and was studied by Elastic Recoil Detection Analysis with Heavy ions and a Time-of-flight detection. A series of MgB2 thin film samples were analyzed, including films produced in situ on Al2O3-C and Si (0 0 1) substrates (with higher T-c and lower T-c) with an "on-axis" geometry, and films produced in situ with an "off-axis" geometry. The amount of oxygen detected in these films appears to be correlated with the T-c of the films, the higher the T-c the lower the oxygen content. The superconducting properties of the examined thin films are discussed in the context of the ERDA results. (C) 2008 Elsevier B.V. All rights reserved.

Oxygen incorporation in MgB2 thin films during their fabrication process has a strong influence on the future properties of the films, and was studied by Elastic Recoil Detection Analysis with Heavy ions and a Time-of-flight detection. A series of MgB2 thin film samples were analyzed, including films produced in situ on Al2O3-C and Si (0 0 1) substrates (with higher T-c and lower T-c) with an "on-axis" geometry, and films produced in situ with an "off-axis" geometry. The amount of oxygen detected in these films appears to be correlated with the T-c of the films, the higher the T-c the lower the oxygen content. The superconducting properties of the examined thin films are discussed in the context of the ERDA results. (C) 2008 Elsevier B.V. All rights reserved.

Oxygen incorporation in MgB2 thin films during their fabrication process has a strong influence on the future properties of the films, and was studied by Elastic Recoil Detection Analysis with Heavy ions and a Time-of-flight detection. A series of MgB2 thin film samples were analyzed, including films produced in situ on Al2O3-C and Si (0 0 1) substrates (with higher T-c and lower T-c) with an "on-axis" geometry, and films produced in situ with an "off-axis" geometry. The amount of oxygen detected in these films appears to be correlated with the T-c of the films, the higher the T-c the lower the oxygen content. The superconducting properties of the examined thin films are discussed in the context of the ERDA results. (C) 2008 Elsevier B.V. All rights reserved.