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GRAPhEME is a γ-spectrometer developed by CNRS/IPHC Strasbourg (France), in collaboration with EC-JRC Geel (Belgium) and IFIN-HH Bucharest (Romania). With its 6 High Purity Planar Germanium detectors and one fission chamber, GRAPhEME, installed at the EC-JRC GELINA facility, was optimized for measurements of accurate (n, xnγ) cross sections on actinides. The experimental methodology is based on the prompt γ-ray spectroscopy coupled to time-of-flight measurements. In this paper, we present an overview of fifteen years of experiments with GRAPhEME at EC-JRC GELINA facility, illustrated by main achievements to highlight the performances reached by our spectrometer. Beyond the experimental work, a close collaboration with theoreticians has emerged allowing the use of the data produced with GRAPhEME to test and constraint nuclear reaction codes like TALYS, CoH and EMPIRE. In a near future, GRAPhEME will be available to start measurement campaigns at the new neutron beam facility SPIRAL2/NFS. There, studies of (n, 2n) and (n, 3n) reactions will be possible and will complete the work done at EC-JRC GELINA on (n, n) reactions. Despite the amount of cross section data provided by GRAPhEME up to now, the prompt γ-ray spectroscopy method presents some weaknesses that our collaboration tries to overcome. This goes through new calculation schemes based on theoretical modeling constrained on experimental data to infer the total (n, xn) cross section, new instrument to measure conversion electrons but also by being proactive in dissemination activities to make the nuclear structure community aware of our needs about new accurate nuclear structure information on actinides. [ABSTRACT FROM AUTHOR]

An experimental setup used at the CENTA (Centre for Nuclear and Accelerator Technologies) laboratory to carry out IBA (Ion Beam Analysis) techniques is described. PIXE (Particle Induced X-ray Emission) technique offers a unique way of non-destructive elemental analysis using accelerated ion beams. The calibration of instrumental constants (H-values) of SDD and BEGe detectors, used in the setup, is described in detail. The H-value was determined as a function of X-ray energy by using thin MicroMatter standards of chosen elements. The calibrated H-values were then used in GUPIXWIN for the determination of elemental concentrations in two IAEA reference materials, which were compared with reference values. A reasonable agreement was achieved between the measured and reference values, while the calibrated H-values will be used for further analyses. [ABSTRACT FROM AUTHOR]

High electronic excitations in radiation of metallic targets with swift heavy ion beams at the coulomb barrier play a dominant role in the damaging processes of some metals. The inelastic thermal spike model was developed to describe tracks in materials and is applied in this paper to some systems beams/targets employed recently in some nuclear physics experiments. Taking into account the experimental conditions and the approved electron-phonon coupling factors, the results of the calculation enable to interpret the observation of the fast deformation of some targets. [ABSTRACT FROM AUTHOR]

We have recently successfully demonstrated a new technique for production and study of many of the most exotic neutron-rich nuclei at moderate spins. LICORNE, a newly developed directional inversekinematic fast neutron source at the ALTO facility of the IPN Orsay, was coupled to the MINIBALL γ-ray spectrometer to study very neutron rich nuclei using the 238U(n,f) reaction. This reaction and 232Th(n,f), are the most neutron-rich fission production mechanisms achievable and can be used to simultaneously populate hundreds of neutron-rich nuclei up to spins of ~16h. High selectivity in the experiment was achieved via triple γ-ray coincidences and the use of a 400 ns period pulsed neutron beam, a technique which is unavailable to other reaction mechanisms such as spontaneous fission. The pulsing allows time correlations to be exploited to separate delayed γ rays from isomeric states and supresses unwanted γ-rays from beta decay. In Autumn 2017, the ν-ball array will be operational at the ALTO facility of the IPN Orsay. This high efficiency hybrid Ge-LaBr3 spectrometer based around 24 clover Ge detectors, 10 co-axial Ge detectors and 20 LaBr3 scintillators will help to further refine the technique and achieve a large increase in the current observational limit. [ABSTRACT FROM AUTHOR]

μX-ray spectra for Z=9-90 were measured with HPGe detectors and muonic beams of PSI (Villigen, Switzerland) [1]. The results are presented as electronic atlas composed of graphic plots. The atlas is available at JINR site [2]. [ABSTRACT FROM AUTHOR]

AREVA Mines and the Nuclear Measurement Laboratory of CEA Cadarache are collaborating to improve the sensitivity and precision of uranium concentration evaluation by means of gamma measurements. This paper reports gamma-ray spectra, recorded with a high-purity coaxial germanium detector, on standard cement blocks with increasing uranium content, and the corresponding MCNP simulations. The detailed MCNP model of the detector and experimental setup has been validated by calculation vs. experiment comparisons. An optimization of the detector MCNP model is presented in this paper, as well as a comparison of different nuclear data libraries to explain missing or exceeding peaks in the simulation. Energy shifts observed between the fluorescence X-rays produced by MCNP and atomic data are also investigated. The qualified numerical model will be used in further studies to develop new gamma spectroscopy approaches aiming at reducing acquisition times, especially for ore samples with low uranium content. [ABSTRACT FROM AUTHOR]

In this study, the levels of the natural and artificial radioactivity in soil samples collected at various depths from Algerian agricultural region El-Athmania Mila was measured. Activity concentrations of the concerned radionuclides were determined by gamma-ray spectrometry using a high-purity germanium detector. The activity concentrations of 226Ra, 232Th and 40K were found unchanged as a function of depth and ranged from 23.72±2.37to 65.47±5.06 Bq.kg-1 for 226Ra, from 26.45±0.78 to 27.10±0.80 Bq.kg-1 for 232Th and from 220.80±10.01 to 260.70±8.24 Bq.kg-1 for 40K respectively. To evaluate the radiological hazard of radioactivity in samples, the radium equivalent activity (Raeq), the absorbed dose rate (D), the annual effective dose and the external (Hex) and internal hazard indices (Hin) were calculated. The mean of the excess lifetime cancer risk observed in this study are under the world's mean values. [ABSTRACT FROM AUTHOR]

A new helium-gas stripper system has been applied at the ~11 A MeV uranium beam of the Radioactive Isotope Beam Factory of the RIKEN accelerator facility. Although the gas stripper is important for the heavy-ion accelerator facility, the residual radiation that is generated is a serious problem for maintenance work. The residual dose was evaluated by using three-layered activation samples of aluminium and bismuth. The γ-rays from produced radionuclides with in-flight fission of the 238U beam and from the material of the chamber activated by neutrons were observed by using a Ge detector and compared with the values calculated by using the Monte-Carlo simulation code PHITS. [ABSTRACT FROM AUTHOR]

Preliminary neutron capture cross section of 120Sn, 122Sn and 124Sn were obtained in the energy range from 20meV to 4 keV with the array of germanium detectors in ANNRI at MLF,J-PARC. The results of 120Sn, 122Sn and 124Sn were obtained by normalizing the relative cross sections to the data in JENDL-4.0 at the largest 426.7-, 107.0- and 62.05-eV resonances, respectively. The 67.32- and 150-eV resonances for 120Sn and the 579- and 950-eV resonances for 124Sn which are listed in JENDL-4.0 and/or ENDF/B VII.1 were not observed. [ABSTRACT FROM AUTHOR]

A new data acquisition system (DAQ system) has been developed at the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) facility in the Japan Proton Accelerator Research Complex, Materials and Life Science Experimental Facility (J-PARC/MLF). DAQ systems for both the Ge detector system and the Li-glass detector system were tested by using a gold sample. The applicability of the time-offlight method was checked. System performance was evaluated on the basis of digital conversion nonlinearity, energy resolution, multi-channel coincidence and dead time. [ABSTRACT FROM AUTHOR]

VENUS-F is a fast zero power reactor with 30 wt% U fuel and Pb/Bi as a coolant simulator. Depending on the experimental configuration, various neutron spectra (fast, epithermal, and thermal islands) are present. This paper gives a review of the nuclear instrumentation that is applied for reactor control and in a large variety of physics experiments. Activation foils and fission chambers are used to measure spatial neutron flux profiles, spectrum indices, reactivity effects (with positive period and compensation method or the MSM method) and kinetic parameters (with the Rossi-alpha method). Fission chamber calibrations are performed in the standard irradiation fields of the BR1 reactor (prompt fission neutron spectrum and Maxwellian thermal neutron spectrum). [ABSTRACT FROM AUTHOR]

The Germanium Detector Array (GERDA) experiment is searching for neutrinoless double beta (0vββ) decay of 76Ge, a lepton number violating nuclear process predicted by extensions of the Standard Model. GERDA is an array of bare germanium diodes immersed in liquid argon located at the Gran Sasso National Laboratory (LNGS) in Italy. The results of the GERDA Phase I data taking with a total exposure of 21.6 kg yr and a background index of 0.01 cts/(keV kg yr) are presented in this paper. No signal was observed and a lower limit of T0v1/2 > 2.1 x 1025 yr (90% C.L.) was derived for the half-life of the 0vββ decay of 76Ge. Phase II of the experiment aims to reduce the background around the region of interest by a factor of ten. [ABSTRACT FROM AUTHOR]

In this paper, we have performed Photoactivation Analysis (PAA), a non-destructive method, which is used to determine elemental concentration of any sample. This paper presents the first use of this method in medical sciences in Turkey. The method was applied to the determination of Sr/Ca ratios in teeth. The collected teeth samples and standards (SrO and CaCO3) have been irradiated for a fixed time interval with high energy photons. The photons were generated by a clinical linear accelerator (cLINAC). The photon end-point energy was 18 MeV. The energy and the time interval were sufficient to achieve good activation. Afterward, the samples and standards have been analysed with gamma spectroscopic analysis by using an HPGe detector system. By analysing many samples, a database of Sr/Ca ratios will be created at Nuclear Research and Application Center (NUBA). In this paper we present a small subset of the already analysed data as an example of our capabilities and goal. We hope to set an example for future studies. [ABSTRACT FROM AUTHOR]

Establishing of radioactivity planes in foodstuff has emphasis because it allows the evaluation of population exposure to radiation by take nourishment. In this paper, the activity concentrations of 226Ra, 232Th, 40K and 137Cs were determined in cabbage samples collected from Samsun city of Turkey using a gamma ray spectrometry method with a HPGe detector. The mean concentration value of 226Ra, 232Th, 40K 0.18±0.003 Bqkg-1, respectively. The calculated total annual effective dose received from 226Ra, 232Th, 40K and 137Cs due to cabbage samples by population of Samsun province was quite lower than the World and 137Cs in cabbage samples were 1.11±0.03 Bqkg-1, 1.44±0.04 Bqkg-1, 743.75±21.21 Bqkg-1 and 0.18±0.003 Bqkg-1, respectively. The calcul and 137Cs due to cabbage samples by pop average value as suggested by UNSCEAR. [ABSTRACT FROM AUTHOR]