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Abstract Several simple accelerator-driven system (ADS) setups were irradiated by relativistic proton and deuteron beams in last years at the Nuclotron synchrotron site of the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. This paper is dedicated to a 4 GeV deuteron irradiation of a setup called Energy plus Transmutation (E+T), consisting of a lead target, natural uranium blanket, and polyethylene shielding. This paper represents the finalization of data analysis and concludes systematics of the proton and deuteron experiments carried out with the E+T setup. Activation detectors served for monitoring of proton and deuteron beams and for measurements of neutron field distribution in model ADS studies. Products of reactions with thresholds up to 106 MeV as well as non-threshold reactions were observed in the samples. The yields of the produced isotopes were determined using the gamma-ray spectrometry and compared with Monte Carlo simulations performed with the MCNPX transport code. Highlights • Model ADS setup consisting of Pb+U was irradiated by 4 GeV deuteron beam. • Activation samples were used to measure the produced neutron field distribution. • Products of neutron reactions with threshold up to 106 MeV were measured. • Relativistic deuteron reactions on Cu used for the beam fluence determination. • The 40 MeV border between cascade and evaporation phases of spallation observed. [ABSTRACT FROM AUTHOR]

Abstract The intensities of γ -rays from the 196m2Au decay adopted in 1998 and 2007 ENSDF evaluations differ up to 20%. Gold samples were irradiated in intensive neutron fluxes with energies up to 35 MeV to produce the isotopes 196Au in all isomeric states. The intensities of gammas from the radioactive decay of the isomer 196m2Au were measured by means of the nuclear γ -ray spectrometry (HPGe detectors) and compared to the existing adopted data. [ABSTRACT FROM AUTHOR]

The spallation lead target in the “Energy plus Transmutation” set-up, covered with uranium blanket, was irradiated by the 1.6GeV deuteron beam from the Nuclotron accelerator at the Joint Institute for Nuclear Research in Dubna. The neutrons generated in the subcritical uranium blanket are used to activate the radioactive uranium and thorium samples outside the blanket. Rates of the ( n, $ \gamma$) , ( n, f) and ( n, 2 n) reactions are determined for some residual nuclei. The ratio of the reaction rates R( n, 2 n)/ R( n, f) is estimated to be 27(9)%. Contributions of the neutrons with energy En > 20 MeV to the ( n, f) reaction rate is ∼ 57% for 232Th and ∼ 37% for natU , respectively. To compare with the experimental results, the reaction rates are simulated by generating the neutron fluxes employing two different models, the beam shapes by the MCNPX 2.6.c code and making use of the appropriate libraries of cross-sections. The transmutation power of the set-up is estimated using the average ( n, $ \gamma$) and ( n, 2 n) reaction rates and compared with some of the results of the TARC experiment. [ABSTRACT FROM AUTHOR]

Abstract: A thick Pb-target with a U-blanket surrounded by a polyethylene moderator was irradiated with 0.7–2.5GeV proton and deuteron beams. Neutron production was studied with activation detectors. Neutron multiplicity was determined using a modified form of the water-bath/activation-foil method. The experimental results were compared with Monte Carlo simulations performed with the MCNPX code (INCL4+ABLA). Neutron multiplicities on the Pb/U-setup were also compared with data measured on thick Pb-target irradiated with 0.1–4.5GeV proton beams to date. [Copyright &y& Elsevier]