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Accelerator Mass Spectrometry (AMS) is presently the most sensitive technique for the measurement of long-lived actinides, e.g. 236U and xPu isotopes. A new actinide AMS system, based on a 3-MV pelletron tandem accelerator, is operated at the Center for Isotopic Research on Cultural and Environmental Heritage (CIRCE) in Caserta, Italy. In this paper we report on the procedure adopted to increase the 236U abundance sensitivity as low as possible. The energy and position determinations of the 236U ions, using a 16-strip silicon detector have been obtained. A 236U/238U isotopic ratio background level of about 2.9x10-11 was obtained, summing over all the strips, using a Time of Flight-Energy (TOF-E) system with a 16-strip silicon detector (4.9x10-12 just with one strip). [ABSTRACT FROM AUTHOR]

The 3He(α, γ)7Be reaction plays an important role in the interpretation of the results of the solar neutrino experiments, since the estimate of the oscillation parameters relies on the solar neutrino spectrum, calculated by solar models. The high energy component in this spectrum is mainly produced by the decay of 7Be and 8B. The uncertainty in the 3He(α, γ)7Be cross section is also one of the largest contributions to the uncertainty on the predicted primordial 7Li abundance in Big Bang Nucleosynthesis calculations. Previous measurements of the 3He(α, γ)7Be cross section have been performed detecting the capture γ-rays or, alternatively, measuring the activity of the synthesized 7Be. While the results of the two different approaches agree on the energy dependence of the astrophysical S factor, they disagree in the extrapolated S34(0) value at a 3σ level. A novel approach uses the European Recoil separator for Nuclear Astrophysics (ERNA) to detect directly the 7Be ions produced in the reaction and, additionally, the coincident detection of the capture γ-rays. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Radioactive ion implantation allows non-contacting, online wear measurements with sub micrometric sensitivity to be performed, by monitoring the removed and/or residual activity on parts subject to wear. Comparative studies of different materials, including those who exhibit a low resistance to radiation damage, can be easily performed by means of this technique. A project has started at the TTT3 tandem of the University “Federico II” in Naples, Italy, in order to exploit such technique using a 7Be ion beam, that was developed to study the astrophysical important reaction 7Be(p,γ)8B. The 7Be ion beam is produced using a ion sputter source and accelerated to an energy up to 8.0 MeV. A novel setup allows control of the implanted ion depth distribution, and is a crucial point for the application of this technique. The 7Be ion beam production and implantation procedures are discussed. Finally, the results of some test measurements are presented. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

The article focuses on gamma ray detection possibilities in recoil separator for nuclear physics in Europe. Gamma ray data is useful but still with inadequate precision. Different amplitudes involved in the radiative capture is identified. The ground state transition at the energy is produced by the contribution of the tails of the neighboring resonances.