Emanation thermal analysis study of a sol-gel precursor for silica-titania waveguides

Emanation Thermal Analysis (ETA) was demonstrated as a tool for the characterization of microstructure changes of a sol-gel precursor for silica-titania layers deposited on the glass plate to be used as planar waveguides. Temperature ranges of 280-330 and 380-500°C, respectively, in which the densification of the layers took place, were determined by ETA under in situ conditions of the sample heating. Results of thermogravimetry were compared with the ETA data. This revised version was published online in August 2006 with corrections to the Cover Date.     

Project of an internal target for the antiproton ring at FAIR

The case of the internal target for the hyper-nuclear experiment of the PANDA (antiproton Annihilation at Darmstadt) Collaboration at the High Energy Storage Ring of Facility for Antiproton and Ion Research is illustrated. After a discussion of the problems arising from the interaction of a solid internal target with an antiproton beam, the design of material, shape and sizes of a target satisfying the experimental requirements is presented. The techniques used to produce a prototype of this target are illustrated. Then the results of the tests performed on the prototype for investigating the properties (purity, radiation hardness, structure modifications after shaping) are reported and the plan of the future activity is pointed out.     

Lateral IBIC characterization of single crystal synthetic diamond detectors

In order to evaluate the charge collection efficiency (CCE) profile of single‐crystal diamond devices based on a p‐type/intrinsic/metal configuration, a lateral Ion Beam Induced Charge (IBIC) analysis was performed over their cleaved cross sections using a 2 MeV proton microbeam. CCE profiles in the depth direction were extracted from the cross‐sectional maps at variable bias voltage. IBIC spectra relevant to the depletion region extending beneath the frontal Schottky electrode show a 100% CCE, with a spectral resolution of about 1.5%. The dependence of the width of the high efficiency region from applied bias voltage allows the constant residual doping concentration of the active region to be evaluated. The region where the electric field is absent shows an exponentially decreasing CCE profile, from which it is possible to estimate the diffusion length of the minority carriers by means of a drift–diffusion model. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Ion beam mixing of FeNi3 multilayers

An Fe/Ni multilayer of overall FeNi₃ composition, prepared by Joule effect deposition, has been irradiated with 200 keV krypton ions at a nominal dose of 5×10¹⁵ions/cm² to induce mixing at the interface. Depth profiling AES, RBS, XRD (glancing angle) and CEMS have been used to characterize the samples before and after irradiation and also after subsequent mild annealing. In the final structure, we have recognized the presence of embryos of an ordered FeNi₃ superlattice.     

Preparation and characterisation of isotopically enriched Ta2O5 targets for nuclear astrophysics studies

Level energies in two-quasiparticle (2qp) structures in ¹⁵⁶ ₆₁Pm₉₅ are evaluated using the phenomenological rotor-particle model for odd-odd deformed nuclei with the inclusion of the residual p-n interaction contribution. Using these results as location guides, the experimental data from a recent ¹⁵⁶Nd decay study are used to construct a level scheme for ¹⁵⁶Pm with excitation energies upto 550 keV, wherein 26 (out of 30) ????s reported in ¹⁵⁶Nd decay are incorporated. Spin-parities and configuration assignments are suggested for 15 levels, in addition to the two isomers, in this energy domain. These investigations point to the need for information on higher-energy ????s and on ??-?? and ??-?? coincidence data from ¹⁵⁶Nd ??-decay to confirm these assignments.     

A new study of 25Mg(\alpha,n) 28Si angular distributions at E_{\alpha} =3-5 MeV

Heavy neutron-rich nuclei close to N = 126 were produced by fragmentation of a 1A GeV ²⁰⁸Pb beam at the FRS at GSI. The β-decay half-lives of 7 nuclides have been determined using a novel numerical analysis method. The half-lives of ^202,199Ir, ^200,199Os and ¹⁹⁶Re are reported for the first time. The comparison of the data with model calculations provides indications on the importance of first-forbidden transitions on the β-decay of nuclei around N = 126 and Z < 82.