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The activation cross sections for production of 51Cr, 52,54,56Mn, 59Fe, and 55,56,57,58Co radioisotopes in deuteron-induced reactions on natural Fe were measured at deuteron energies up to 20 MeV. Then, within an extended analysis of deuteron interactions with natFe, all processes from elastic scattering until the evaporation from fully equilibrated compound system have been taken into account. Following the available elastic-scattering data analysis that supports the deuteron optical potential for reaction cross sections calculations, increased attention is paid especially to the breakup (BU) mechanism and direct reactions (DR). The deuteron activation cross-section analysis is completed by consideration of the preequilibrium and compound-nucleus contributions, corrected for decrease of the total reaction cross section due to the leakage of the initial deuteron flux towards BU and DR processes. The overall agreement of the measured data and model calculations validates the description of nuclear mechanisms taken into account, particularly the strong effects of direct interactions that have still not been appropriately considered within previous deuteron activation evaluations. [ABSTRACT FROM AUTHOR]

Recent accurate data obtained for the isomeric cross section of the 197Au(n, In) reaction provide a valuable opportunity to consider the question of the effective moment of inertia of the nucleus within a local consistent model analysis of all available reaction data for the 197Au target nucleus. Thus, a definite proof of a moment of inertia equal to that of the rigid-body has been obtained for the 196Au nucleus, while indications infer about half the rigid-body for 194Ir. [ABSTRACT FROM AUTHOR]

The dominance of the deuteron breakup mechanism around the Coulomb barrier is shown by an analysis of the 231Pa(d, 3n)230U reaction excitation function, while the same attribute was found within a former assessment for the deuteron-induced fission. The present alternative result is obtained by taking into account, in addition to pre-equilibrium and compound-nucleus processes, the opposite effects of deuteron breakup, namely the decrease of the deuteron total reaction cross section, and the inelastic-breakup enhancement of various deuteron-induced reaction channels. [ABSTRACT FROM AUTHOR]

Background: Recent high-precision measurements of α-induced reaction data below the Coulomb barrier have pointed out questions about the α-particle optical-model potential (OMP) which are still unanswered within various mass ranges. Purpose: The applicability of previous optical potential and eventual uncertainties and/or systematic errors of the OMP assessment at low energies can be further considered on this basis. Method: Nuclear model parameters based on the analysis of recent independent data, particularly γ-ray strength functions, have been involved within statistical model calculation of the (α,x) reaction cross sections. Results: The above-mentioned potential provides a consistent description of the recent α-induced reaction data with no empirical rescaling factors of the γ and/or nucleon widths. Conclusions: A suitable assessment of α-particle optical potential below the Coulomb barrier should involve the statistical-model parameters beyond this potential on the basis of a former analysis of independent data. [ABSTRACT FROM AUTHOR]

Abstract: The neutron transmission of natural hafnium samples have been measured within the 2 eV to 50 keV energy range at the white neutron source GELINA of the Institute for Reference Materials and Measurements (IRMM) in Geel, Belgium. Data sets for two temperatures (77 K and 300 K) and three sample thicknesses (1 mm, 2 mm, 15 mm) have been simultaneously analyzed in terms of Reich–Moore parameters. The ESTIMA technique in association with the generalized SPRT method were used to obtain a consistent set of l-dependent average resonance parameters. For each hafnium isotope, scattering radius , neutron strength function , distant level parameter , mean level spacing and average radiation width are given and compared with results reported in the literature. The capture and total cross sections calculated by the CONRAD code using this set of average parameters were successfully compared to experimental data retrieved from EXFOR. [Copyright &y& Elsevier]

Abstract: An extended analysis has been performed of elastic-scattering and reaction cross-sections of deuterons on the nucleus, for deuteron energies from 3 to 60MeV, based on a semi-microscopic optical potential with a double-folding real part and phenomenological imaginary and spin-orbit terms. An increased effort is devoted to the breakup mechanism, the analysis of proton-emission spectra and angular distributions from deuteron-induced reactions on nuclei from Al to Pb, at incident energies from 15 to 80MeV, providing the energy- and mass-dependence of the breakup mechanism contribution. The corresponding direct-reaction cross-sections within the same energy range has then been analyzed, the improved description of both the elastic-scattering and reaction measured data backing the proper use of these optical potentials for deuteron activation assessment. [Copyright &y& Elsevier]

The cross section for the natMo(n, x)94Nb reaction was measured in the energy range from 14.5 to 20.3 MeV using both conventional γ-rayspectrometry and the ultra low-level γ-ray spectrometry (ULGS) facility in the underground laboratory HADES. The exceptionally long half-life of the activation product 94Nb of 20300 years required a long irradiation, a large sample and a special irradiation geometry, to allow a simultaneous determination of the three data points. This measurement presents the first data above 14 MeV. The data are well described by model calculations with the STAPRE-H code that include the 94Mo(n, p)94Nb and 95Mo(n, np)94Nb reactions. [Copyright &y& Elsevier]

Background: Specific noncompound processes such as breakup (BU) and distinct direct reactions (DR) make deuteron-induced reactions different from reactions with other incident particles. Significant discrepancies with measured cross sections were caused by taking into account only the pre-equilibrium emission (PE) and compound-nucleus (CN) mechanisms while microscopic calculation of inclusive BU and DR cross sections is still investigated numerically. Thus, reaction cross sections recommended most recently for high-priority elements are still based on data fit. Purpose: Accurate new measurements of low-energy deuteron-induced reaction cross sections for natural Cr target can enhance the related database and the opportunity for a unitary and consistent account of the involved reaction mechanisms. Methods: The activation cross sections of 51, 52, 54 Mn, 51 Cr, and 48 V nuclei for deuterons incident on natural Cr at energies up to 20 MeV were measured by the stacked-foil technique and high resolution γ spectrometry using the U-120M cyclotron of the Center of Accelerators and Nuclear Analytical Methods (CANAM) of the Nuclear Physics Institute of the Czech Academy of Sciences (NPI CAS). They, as well as formerly available data for deuteron interactions with Cr isotopes up to 60 MeV, are the object of an extended analysis of all processes from elastic scattering until the evaporation from a fully equilibrated compound system, but with particular attention given to the BU and DR mechanisms. Results: The new measured activation excitation functions proved essential for the enrichment of the deuteron database, while the theoretical analysis of all available data strengthens for the first time their consistent account, provided that a suitable BU and DR assessment is completed by the assumption of PE and CN contributions corrected for decrease of the total-reaction cross section due to the leakage of the initial deuteron flux towards BU and DR processes. Conclusions: The suitable description of nuclear mechanisms involved within deuteron-induced reactions on chromium, taking into account especially the BU and DR direct processes, is validated by an overall agreement of the calculated and measured cross sections, including particularly the new experimental data at low energies. [ABSTRACT FROM AUTHOR]