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Background: Recent studies of deuteron-induced reactions around the Coulomb barrier B pointed out that numerical calculations for deuteron-induced reactions are beyond current capabilities. The statistical model of nuclear reactions was used in this respect since the compound-nucleus (CN) mechanism was considered to be responsible for most of the total-reaction cross section σR in this energy range. However, specific noncompound processes such as the breakup (BU) and direct reactions (DR) should be also considered for the deuteron-induced reactions, making them different from reactions with other incident particles. Purpose: The unitary and consistent BU and DR consideration in deuteron-induced reactions is proved to yield results at variance with the assumption of negligible noncompound components. Method: The CN fractions of σR obtained by analysis of measured neutron angular distributions in deuteron-induced reactions on 27Al, 56Fe, 63,65Cu, and 89Y target nuclei, around B, are compa/red with the results of an unitary analysis of every reaction mechanism. The latter values have been supported by the previously established agreement with all available deuteron data for 27Al, 54,56-58,natFe, 63,65,natCu and 93Nb. Results: There is a significant difference between the larger CN contributions obtained from measured neutron angular distributions and calculated results of an unitary analysis of every deuteron-interaction mechanism. The decrease of the latter values is mainly due to the BU component. Conclusions: The above-mentioned differences underline the key role of the breakup and direct reactions that should be considered explicitly in the case of deuteron-induced reactions. [ABSTRACT FROM AUTHOR]

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]

The activation cross sections of (d, p), (d, 2M), (d, 2np + nd + t), (d, 2nα), and (d, pα) reactions on 93Nb were measured in the energy range from 1 to 20 MeV using the stacked-foil technique. Then, within a simultaneous analysis of elastic scattering and reaction data, the available elastic-scattering data analysis was carried out in order to obtain the optical potential for reaction cross-section calculations. Particular attention was paid to the description of the breakup mechanism and direct reaction stripping and pick-up, followed by pre-equilibrium and compound-nucleus calculations. The measured cross sections as well as all available deuteron activation data of 93Nb were compared with results of local model calculations carried out using the codes FRESCO and STAPRE-H and both default and particular predictions of the code TALYS-1.4 and TENDL-2012-evaluated data. [ABSTRACT FROM AUTHOR]

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]

Comparative assessment of the total breakup proton-emission cross sections measured for 56 MeV deuteron interaction with target nuclei from 12C to 209Bi, with an empirical parametrization and recently calculated microscopic neutron-removal cross sections was done at the same time with similar data measured at 15, 25.5, 70, and 80 MeV. Comparable mass dependencies of the elastic-breakup (EB) cross sections provided by the empirical parametrization and the microscopic results have been also found at the deuteron energy of 56 MeV, while the assessment of absolute-values variance up to a factor of two was not possible because of the lack of EB measurements at energies higher than 25.5 MeV. While the similarities represent an additional validation of the microscopic calculations, the cross-section difference should be considered within the objectives of further measurements. [ABSTRACT FROM AUTHOR]

Background: The high complexity of the deuteron-nucleus interaction from the deuteron weak binding energy of 2.224 MeV is also related to a variety of reactions induced by the deuteron-breakup (BU) nucleons. Thus, specific noncompound processes as BU and direct reactions (DR) make the deuteron-induced reactions so different from reactions with other incident particles. The scarce consideration of only pre-equilibrium emission (PE) and compound-nucleus (CN) mechanisms led to significant discrepancies with experimental results so that recommended reaction cross sections of high-priority elements as, e.g., Ni have mainly been obtained by fit of the data. Purpose: The unitary and consistent BU and DR account in deuteron-induced reactions on natural nickel may take advantage of an extended database for this element, including new accurate measurements of particular reaction cross sections. Method: The activation cross sections of 64,61,60Cu, 65,57Ni, and 55,56,57,58,58m,60Co nuclei for deuterons incident on natural Ni at energies up to 20 MeV, were measured by the stacked-foil technique and high-resolution gamma spectrometry using U-120M cyclotron of CANAM, NPI CAS. Then, within an extended analysis of deuteron interactions with Ni isotopes up to 60 MeV, all processes from elastic scattering until the evaporation from fully equilibrated compound system have been taken into account while an increased attention is paid especially to the BU and DR mechanisms. Results: The deuteron activation cross-section analysis, completed by consideration of the PE and CN contributions corrected for decrease of the total-reaction cross section from the leakage of the initial deuteron flux towards BU and DR processes, is proved satisfactory for the first time to all available data. Conclusions: The overall agreement of the measured data and model calculations validates the description of nuclear mechanisms taken into account for deuteron-induced reactions on Ni, particularly the BU and DR that should be considered explicitly. [ABSTRACT FROM AUTHOR]