Observation of the 3n evaporation channel in the complete hot-fusion reaction 26Mg + 248Cm leading to the new superheavy nuclide 271Hs

The analysis of a large body of heavy ion fusion reaction data with medium-heavy projectiles (6 < or = Z < or = 18) and actinide targets suggests a disappearance of the 3n exit channel with increasing atomic number of the projectile. Here, we report a measurement of the excitation function of the reaction (248)Cm ((26)Mg,xn)(274-x)Hs and the observation of the new nuclide (271)Hs produced in the 3n evaporation channel at a beam energy well below the Bass fusion barrier with a cross section comparable to the maxima of the 4n and 5n channels. This indicates the possible discovery of new neutron-rich transactinide nuclei using relatively light heavy ion beams of the most neutron-rich stable isotopes and actinide targets.

Production of 177Lu at the new research reactor FRM-II: Irradiation yield of 176Lu177Lu

Due to its physical and chemical characteristics, 177Lu is a very attractive radionuclide for use in nuclear medicine. This paper introduces a method for a precise calculation of the irradiation yield of 177Lu produced by neutron activation of 176Lu in a nuclear reactor. The calculation is based on the Westcott convention which requires the knowledge of the neutron flux parameters. In this work, the neutron flux parameters of the new research reactor FRM-II (Garching, Germany) were determined and the stability of thermal neutron flux and thermal neutron flux temperature was monitored. The comparison of theoretically calculated and experimentally determined yield for Lu176(n,gamma)Lu177 reaction is presented.