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Abstract: Quasi-monoenergetic neutron beams, in the energy range 7–11.5MeV, produced via the 2H(d,n) reaction, have been used at the 5.5MV tandem T11/25 Accelerator Laboratory of NCSR “Demokritos”. The flux variation of the neutron beam is monitored with a BF3 detector, while the absolute flux is obtained with respect to reference reactions. An investigation of the energy dependence of the neutron fluence has been carried out using two independent techniques: by a liquid scintillator BC501A detector and deconvolution of its recoil energy spectra performed by means of the DIFBAS code, as well as via the multiple foil activation technique in combination with the SULSA unfolding code. The neutron facility has also been characterized by means of Monte Carlo simulations with MCNP5. [Copyright &y& Elsevier]

Abstract: Fission cross-section measurements with the Fast Ionization Chamber (FIC) at the CERN n_TOF facility were challenged by intense signals due to γ-rays and ultra-relativistic particles from the impact of the 20GeV proton pulses on the neutron spallation target. A method for analyzing the data taken with Flash Analog to Digital Converters (FADC) was developed to treat these problems in an automated way to provide a reliable background subtraction and a fit routine for identifying fission events even at high energies. The analysis is illustrated at the example of the fission cross-section of 238U relative to that of 235U in the energy range from 40keV to 300MeV. [Copyright &y& Elsevier]

Abstract: Systematic experimental and theoretical investigations of the 70,72,73,74Ge(n,p)70,72,73,74Ga reaction cross-sections are presented in the energy range from threshold to about 17MeV neutron energy. The 72,73Ge(n,p)72,73Ga reaction cross-sections were measured from 8.8 to 11.4MeV by using the activation method, relative to the 27Al(n, α)24Na reference reaction. The quasi-monoenergetic neutron beams were produced via the 2H(d,n)3He reaction at the 5MV Van de Graaff (VdG) Tandem T11/25 accelerator of NCSR “Demokritos”. Statistical model calculations using the code EMPIRE (version 2.19) and taking into account pre-equilibrium emission were performed on the data measured in this work as well as on data reported in the literature. [Copyright &y& Elsevier]

Si(1 0 0) and (1 1 1) crystals were irradiated in the random as well as in the channeling direction, using 5 MeV 19F+ ions, to a maximum fluence of approximately 1×1017 particles/cm2. The occurring deep implanted profiles were subsequently investigated using the Resonant Nuclear Reaction Analysis technique in the energy range Ep=950–1200 keV. The reaction 19F(p,αγ)16O reaction exhibits a strong resonant behavior in the above mentioned energy range, thus providing an excellent tool for the depth profiling of fluorine, yielding minimum detection limits of the order of a few ppm. The occurring profiles are analyzed with SRIM and c-TRIM codes and an attempt is made to explain the characteristics of the experimental spectra, as well as to compare with results already existing in literature. [Copyright &y& Elsevier]

In the present work, the 6 Li(d,d 0 ) 6 Li elastic scattering differential cross sections were measured in the energy range E d,lab = 940 – 2000 keV for Elastic Backscattering Spectroscopy (EBS) purposes, using thin lithium targets, made by evaporating isotopically enriched 6 LiF powder on self-supporting carbon foils, with an ultra-thin Au layer on top for normalization purposes. The experiment was carried out in deuteron beam energy steps of 20 or 30 keV and for the laboratory scattering angles of 125°, 140°, 150°, 160°, and 170°. [ABSTRACT FROM AUTHOR]

The evaluated proton differential cross sections suitable for the Elastic Backscattering Spectroscopy (EBS) analysis of nat Si and 16 O, as obtained from SigmaCalc 2.0, have been benchmarked over a wide energy and angular range at two different accelerator laboratories, namely at N.C.S.R. ‘Demokritos’, Athens, Greece and at Ruđer Bošković Institute (RBI), Zagreb, Croatia, using a variety of high-purity thick targets of known stoichiometry. The results are presented in graphical and tabular forms, while the observed discrepancies, as well as, the limits in accuracy of the benchmarking procedure, along with target related effects, are thoroughly discussed and analysed. In the case of oxygen the agreement between simulated and experimental spectra was generally good, while for silicon serious discrepancies were observed above E p,lab = 2.5 MeV, suggesting that a further tuning of the appropriate nuclear model parameters in the evaluated differential cross-section datasets is required. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied the 24Mg(d,p0,1,2) reactions at energies and detection angles suitable for NRA. [•] We studied the natMg(d,d0) differential cross section relative to the Rutherford case. [•] We validated the obtained results via benchmarking experiments. [ABSTRACT FROM AUTHOR]

Abstract: Boron depth profiling presents strong analytical challenges for all Ion Beam Analysis (IBA) techniques. In the past, both the 11B(p,α o)8Be (NRA) and the 11B(p,p 0)11B (EBS) reactions have been proposed and they seem to be quite suitable for analytical purposes. Nonetheless, both reactions have not been adequately studied in literature (as far as data suitable for material analysis in the backscattering geometry are concerned). Moreover, the existing datasets are relatively discrepant. In an attempt to clarify the situation, both reactions were studied in the present work between 135° and 160°, in steps of 5°, for the proton beam energy range between 2.2 and 4.2MeV, in steps of 50keV. An attempt to explain the occurring results in the framework of the resonance mechanism is also presented, along with a comparison with previously published data. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, new, differential cross-section values are presented for the natK(p, p 0) reaction in the energy range E lab =3000–5000keV (with an energy step of 25keV) and for detector angles between 140° and 170° (with an angular step of 10°). A qualitative discussion of the observed cross-section variations through the influence of strong, closely spaced resonances in the p+ 39K system is also presented. Information has also been extracted concerning the 39K(p,α 0) reaction for E lab =4000–5000keV in the same angular range. As a result, more than ∼500 data points will soon be available to the scientific community through IBANDL (Ion Beam Analysis Nuclear Data Library –http://www-nds.iaea.org/ibandl/) and could thus be incorporated in widely used IBA algorithms (e.g. SIMNRA, WINDF, etc.) for potassium depth profiling at relatively high proton beam energies. [Copyright &y& Elsevier]

Abstract: The differential cross-sections of the 28Si(d,p0,p1,p2,p3) reactions for the determination of the depth distribution of silicon in near-surface layers of materials have been determined in the projectile energy region E d,lab =1500–2000keV. The experiment was carried out in large energy steps of ∼50keV and for six detector angles between 145° and 170° (in steps of 5°). The obtained experimental data, although in principle suitable for Nuclear Reaction Analysis (NRA) studies, they present strong fluctuations, as expected from nuclear physics theory. A qualitative discussion of these fluctuations is also presented. The results are also compared to recent data from literature, taken at 150°. [Copyright &y& Elsevier]

Abstract: The differential cross-sections of the 11B(d, α 0, α 2,p0) reactions for the determination of the depth distribution of boron in near-surface layers of materials have been determined in the projectile energy region E d,lab =900−1200keV. The experiment was carried out in energy steps of 25keV and for four detector angles between 140° and 170° (in steps of 10°). The obtained experimental data are suitable for Nuclear Reaction Analysis (NRA) studies. A qualitative discussion of the observed cross-section variations through the influence of broad resonances in the d+ 11B system is also presented. The results are also compared to data from literature, when present, and are validated through a benchmarking experiment using a high purity thick B4C target. [Copyright &y& Elsevier]

Abstract: The differential cross-sections of the 10B(d,α0) reaction, for the determination of the depth distribution of boron in near-surface layers of materials, have been determined in the projectile energy region E d,lab =900–2000keV. The experiment was carried out in energy steps of 25keV and for eight detector angles between 135° and 170° (in steps of 5°). The obtained experimental data are suitable for nuclear reaction analysis (NRA) studies. The various aspects of the 10B(d,α) reaction, namely the absence of the α1 transition from the experimental spectra, the induced background from three-body kinematics and the 8Be breakup are discussed and analyzed. The results are compared to the ones already existing in the literature and an attempt is made to explain the occurring similarities and differences. A qualitative description of the observed cross-section variations through the influence of overlapping resonances in the d+10B system is also attempted. [Copyright &y& Elsevier]

Abstract: The differential cross-sections of the 10B(d,p0,1,2,3,4–5,6) reactions for the determination of the depth distribution of boron in near-surface layers of materials have been determined in the projectile energy region E d,lab =900–2000keV. The experiment was carried out in energy steps of 25keV and for eight detector angles between 135° and 170° (in steps of 5°). The obtained experimental data are suitable for nuclear reaction analysis (NRA) studies. A qualitative discussion of the observed cross-section variations through the strong influence of overlapping resonances in the d+ 10B system is also presented. [Copyright &y& Elsevier]

Abstract: Cross section measurements of the 174Hf(n,2n)173Hf reaction have been carried out at the VdG Tandem accelerator of NCSR “Demokritos” in Athens, Greece in the neutron energy range 9.8–11.5MeV, using the activation technique. Statistical model calculations based on the Hauser–Feshbach theory have also been performed by using the code EMPIRE-II with different sets of input parameters. The predictions were compared with the data of the present work as well as with data from literature. [Copyright &y& Elsevier]

Abstract: Absolute differential cross section measurements of the 12C(d,p1,2,3)13C reactions were performed in the projectile energy region E d,lab =900–2000keV (in steps of 25keV) and for detector angles between 145° and 170° (in steps of 5°) using as targets 99.9% purity self-supported natural carbon (98.9% 12C–1.1% 13C) foils of nominal thickness ca. 1×1018 at/cm2. The overall error in the absolute differential cross section measurements varied around 10–15% in most of the cases. The results, presented in both graphical and tabular forms, are compared with already published data. The strong influence of the resonance mechanism is presented and discussed. [Copyright &y& Elsevier]

Abstract: The differential cross-sections of the 12C(d,p0)13C reaction (applied to the determination of the depth distribution of carbon in near-surface layers of materials) were determined in the projectile energy region E d,lab =900–2000keV (in steps of 25keV) and for detector angles between 135° and 170° (in steps of 5°) using as targets 99.9% purity self-supported natural carbon (98.9% 12C–1.1% 13C) foils of nominal thickness ca. 1×1018 at/cm2. The overall error in the absolute differential cross-section measurements varied between ∼6% and 22%. The results were compared with already published data and the occurring differences were explained. [Copyright &y& Elsevier]

Abstract: In the present work, a detailed study of the natC(d,d0) reaction is presented for E d,lab =900–2000keV (in steps of 25keV) and for detector angles between 145° and 170° (in steps of 5°). This reaction complements the implementation of the 12C(d,p0)13C one, when RBS/NRA spectra are required for carbon profiling. The results are compared to those already existing in literature and an attempt is made to explain the occurring differences. A discussion also follows, concerning the existence of resonances and the reaction mechanisms involved. [Copyright &y& Elsevier]

Abstract: In the present work the radiation damage effects induced by 5.88MeV protons in Si and InP crystals, of ∼400 and 325μm thickness, respectively, are examined and analyzed for high fluences ranging between 1016 and 1018 particles/cm2. The irradiation occurs in the random mode by constantly rotating the targets in order to minimize the channeling perturbations, while the control of the induced damage is performed by utilizing the RBS/C technique on the inverse side of the crystals, implementing the proton beam at a reduced energy (E p =1.2MeV). The experimental results reveal impressive extensions of the damage profiles well beyond the end of range of implanted protons. Conventional theoretical calculations, as well as standard SRIM predictions, seem to underestimate the induced effects. An attempt is made in order to explain the experimental spectra via the adoption of the Coulomb explosion model and the results are compared to other already existing in literature for different beam–target combinations. [Copyright &y& Elsevier]

The importance of silicon carbide as a wide band gap semiconductor is widely accepted and well documented. Its excellent physical properties (chemical inertness, high-temperature strength, low thermal expansion, extreme hardness) make it the most promising substitute for traditional semiconductors, especially when high-temperature, high-voltage power, and high-frequency devices are concerned.In the present work, the gradual amorphization of a SiC Lely (21R) crystal when irradiated with 8 MeV 7Li ions in a random direction up to a maximum dose of approximately 1×1016 particles/cm2, is being studied, using the progressive change of channeling parameters for different depths. The results refer to the energy region of ∼1 MeV/nucleon, and an attempt is made in order to explain the peculiarities of the experimental spectra and the mechanism of defect production in SiC. As in previous studies, a change in color was observed after irradiation in the random mode, indicating that the problem of irradiation damage in SiC caused by light ion beams needs further investigation. [Copyright &y& Elsevier]

In the present work, composite AgSiO2 thin coatings, containing metal nanoparticles, were prepared on glass substrates by the sol–gel route. The coatings were thermally treated in oxidative and reductive conditions up to 500 °C for metal nanoparticle formation. The coating structure and the nanoparticle formation were studied by atomic force microscopy and Rutherford backscattering spectroscopy (RBS) techniques. In the case of RBS, 1.4 MeV 4He+ ions were used for all samples, and low energy 16O and 12C ions in selected ones (heavy ion RBS, HIRBS), in order to improve the depth resolution for the profiling of the metal component. The antibacterial activity against Escherichia coli is examined by antibacterial drop test. The coatings exhibited a high antibacterial activity, which was enhanced with the increase of the metal concentration and was reduced with the increase of the particle size of the metal nanoparticles. The possible correlation between the layer interdiffusion after the thermal treatment and the antibacterial activity is examined and analyzed. Although further studies are required, RBS and HIRBS seem to be excellent tools for the quality control in the production of sol–gel thin coatings. [Copyright &y& Elsevier]