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The ongoing Jinping Underground Nuclear Astrophysics experiment (JUNA) will take the advantage of the ultralow background in China Jinping Underground Laboratory (CJPL), high current accelerator driven by on an ECR source and highly sensitive detector to study directly a number of important reactions for the first time within their relevant stellar energy range. A 2.45 GHz ECR ion source is one of its key components to provide 10 emA H + , 10 emA He + and 2.0 emA He 2+ beams for the study of ( p , γ ), ( p,α ), ( α , p ) and ( α , γ ) reactions in the first phase of the JUNA project. Ion beam is extracted from the source with energies up to 50 kV/q. The following low energy beam transport (LEBT) system transports and matches the ion beam from the exit of ion source to the acceleration tube (AT). The design status of the ECR ion source and LEBT system for the JUNA project are presented. The potential risks of the ion source are also discussed and analysed. [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]

Response measurements of a Bonner sphere spectrometer (BSS) were performed for high-energy neutrons up to 400 MeV in quasi-monoenergetic neutron fields at the Research Center for Nuclear Physics (RCNP), Osaka University. The quasi-monoenergetic neutron field was generated by a ^7Li(p,n) reaction with the resulting spectra consisting of a monoenergetic high-energy peak followed by an unwanted continuum tail down to the low-energy region. Two-angle differential measurements for a variety of Bonner spheres were performed to obtain monoenergetic responses by subtracting the tail contributions. Discussions were made on data analysis for tail subtraction. While each Bonner sphere had a different energy response, good agreements were seen in the responses between the MCNPX calculations and the measurements with a suitable subtraction. Response calculations were also made for the whole spectra obtained by unfolding the measured BSS data, with results that reproduce well the measured responses. [ABSTRACT FROM PUBLISHER]

Abstract: In Japan, several monoenergetic and quasi-monoenergetic neutron reference fields are currently operating at several research institutes over a wide energy range 8 keV–390 MeV. These neutron fields are utilized for characterizing and developing neutron detectors as well as for neutron-induced cross section studies, shielding benchmark experiments and irradiation testing of micro-electronic devices. This paper reports the current status of these monoenergetic and quasi-monoenergetic neutron reference fields. [ABSTRACT FROM AUTHOR]

• The comprehensive knowledge of tritium behavior is necessary for the safety and continuous accelerator facility operation. • The present work observed the tritium released from the isotropic graphite, IG-430U, placed in an ionization chamber filled with the air at RT. • The specimen was subsequently sunk in the poured water to continue tritium release observation. • The result implies the existence of a migration period for tritium diffusion that is hard to be explained by the initial tritiumdistribution. For a high power proton accelerator like J-PARC (Japan Proton Accelerator Research Complex), radiation safety is a crucial issue for stable and continuous operation. Tritium is generated by a spallation process even in low- Z materials such as Be and C which are generally applied not only to target materials generating secondary particles but also to other devices irradiated by high energy particles. In general, tritium diffuses easily in a material at high temperature, goes out to the surrounding environment and eventually increases the risk of radiation safety. Thus, tritium is an issue in the maintenance work in short term, and also in storing the spent devices, especially the spent targets in long term due to tritium leakage from and accumulation in a storing container. In J-PARC, isotropic graphite is adopted as the target material for muon production, and thus it is one of the major tritium sources. The present work aims to studying tritium behavior in isotropic graphite to acquire the knowledge applicable to the facility operation. [ABSTRACT FROM AUTHOR]