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The assessment of an α -particle optical model potential for nucleon–induced α -emission within the A ∼ 60 mass-number range [Avrigeanu and Avrigeanu (Eur. Phys. J. A 57:54, 2021)] is completed by analysis of neutron–induced reactions on stable Ni isotopes. The same consistent set of nuclear–model input parameters as well as first uncertainty analysis of calculated cross sections related to the accuracy of independent data formerly used within parameter setting up have been concerned. Description of absorption and emission of α -particles by the same potential is validated, while the pickup direct reaction and Giant Quadrupole Resonance (GQR) α -emission beyond the statistical predictions are confirmed by recent data around the GQR energies. [ABSTRACT FROM AUTHOR]

A consistent set of statistical-model input parameters, validated by analysis of various independent data, makes possible the assessment of an α -particle optical model potential [Phys. Rev. C 90, 044612 (2014)] also for nucleon-induced α -emission within the A ∼ 60 mass-number range. The advantage of recent data for low-lying states feeding is taken as well. Consideration of additional reaction channels leading to increase of the α -emission beyond the statistical predictions has concerned the pickup direct interaction and Giant Quadrupole Resonance similar features. [ABSTRACT FROM AUTHOR]

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]

Recent measurements of α-particle induced reactions on the 64Zn nucleus, below and around the Coulomb barrier, are analyzed simultaneously with α-particle emission at similar energies in proton-induced reactions on Zn isotopes. All open reaction channels, particularly the γ decay, are calculated using consistent input parameters. Additionally, we check a previous optical-model potential for α particles on nuclei within the mass number range 45≤A≤209 [Avrigeanu et al., Phys. Rev. C 90, 044612 (2014)] and prove its correctness in the outgoing channel at least for the present case involving 64Zn and nearby nuclei. The reliability of this potential for incident as well as emitted low-energy α particles is supported by the successful reproduction of high-precision measured data, using no empirical rescaling factor of the γ and/or particle widths. [ABSTRACT FROM AUTHOR]

The recent high-precision measurements of ɑ-particle-induced-reaction data below the Coulomb barrier (B) make possible the understanding of limits and possible improvement of a previous optical model potential (OMP) for ɑ particles on nuclei within the mass number range 45 ≤ A ≤ 209 [M. Avrigeanu et al., Phys. Rev. C 82, 014606 (2010)]. An updated version of this potential is given in the present work concerning mainly an increased surface imaginary-potential depth well below B for A > 130. Moreover, underestimation of reaction cross sections for well-deformed nuclei is removed by using ~ 7% larger radius for the surface imaginary part of this spherical OMP. Improved input parameters based on recent independent data, particularly ɣ-ray strength functions, but no empirical rescaling factor of the ɣ and/or neutron widths have been involved within statistical model calculation of the corresponding (ɑ,x) reaction cross sections. [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]

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]

The cross sections of the 115Sn(α,γ)119Te, 115Sn(α,n)118Te, and 116Sn(α,n)119Te reactions (both on ground and isomeric states) have been measured at effective center-of-mass energies from 9.3 to 14.8 MeV. During a first experiment, enriched self-supporting 115Sn (51.2%) + 116Sn (24.4%) foils were bombarded with an α beam delivered by the Bucharest IFIN-HH Tandem Accelerator. In a second experiment, a highly enriched 116Sn target was irradiated in order to disentangle the experimental cross section contributions due to 115Sn(α,γ)119Te and 115Sn(α,n)118Te reactions obtained in the first measurement. The beam-induced activity was measured with two large volume HPGe detectors in close geometry. The experimental results were compared with theoretical predictions obtained in the framework of the statistical model. [ABSTRACT FROM AUTHOR]

Excitation functions were measured for the 180W(n,2n) 179mW, 182W(n, p) 182Ta, 182W(n, p) 182m2Ta, 182W(n, α) 179m2Hf, 183W(n, p) 183Ta, 183W(n, α) 180mHf, 184W(n, p) 184Ta, 184W(n, α) 181Hf, 186W(n, p) 186Ta, 186W(n, α) 183Hf, 186W(n, n'α) 182mHf, and 186W(n, 2n) 185W reactions from 13.4 to 14.9 MeV. The data of these reactions that are dominant for neutron-induced activation in tungsten were in most cases either defective or incomplete. The experimental results are compared with the results of calculations including all activation channels for the stable W isotopes up to a neutron incident energy of 20 MeV, using two global- and one local-parameter approaches which take into account direct reaction, pre-equilibrium emission (PE), and compound nucleus contributions. The sensitivity of the calculated cross sections to various model approaches and parameters is derived and discussed also in connection with the deviation from unity of calculated-to-experimental activity ratios from benchmark experiments with natural W irradiated by D–T fusion neutrons. The particular importance of the charged-particle emission in this atomic-mass range for PE model validation is discussed and the need for additional data for incident energies above 15 MeV is demonstrated. [Copyright &y& Elsevier]

Results of new cross section measurements are presented for the following neutron-induced reactions: 58Ni(n, p)58m+gCo, 58Ni(n, p)58mCo, 58Ni(n, x)57Co, 58Ni(n, 2n)57Ni, 60Ni(n, p)60m+gCo, 60Ni(n, p)60mCo, 61Ni(n, p)61Co, 61Ni(n, x)60mCo, 62Ni(n, x)61Co, and 59Co(n, 2n)58m+gCo with emphasis on incident energies between 14 and 20 MeV. In addition, new results have been obtained for the isomer ratios of the 58Ni(n, p)58m+gCo, the 60Ni(n, p)60m+gCo and 59Co(n, 2n)58m+gCo reactions.Detailed model calculations were undertaken to study the systematics of (n,xp) reactions on Ni isotopes and the use of the measured isomer ratios for the determination of the effective moment of inertia in the level density expression. Good overall agreement was obtained and, in particular, the case of the 58Ni target isotope now shows a complete physically consistent database that is ideal to test model calculations. The difference in spin between isomer and ground state of ΔJ=3 for the 58Co and 60Co residual nuclei results in a sensitivity to the spin dependence of the level density in these nuclei. However, at present, measurement uncertainties and uncertainties associated with the decay schemes preclude a definitive conclusion about the appropriate value of the effective moment of inertia. A comparison was made between a locally optimized parameter set based on all available data and a global approach. This approach allowed to identify where problems with the global approach can be expected. The locally optimized parameter set includes for the first time gamma-ray strength-functions based on an improved systematics of the gamma-ray widths. [Copyright &y& Elsevier]

Novel measurements of (α,γ) and (α,n) reaction cross sections on the target nucleus 151Eu, close to the reaction thresholds, support the choice of recently proposed parameters of the a-particle optical model potential below the Coulomb barrier. A better understanding of the a-particle optical potential at these energies leads to a statistical model analysis of additional partial cross sections that were measured but not considered within a former model analysis. On this basis we have tentatively assigned a modified Jπ=9¯ spin and parity to the 22.7-h isomer in 154Tb. [ABSTRACT FROM AUTHOR]

Background: Further studies of high-precision measurements of α-induced reaction data below the Coulomb barrier have still raised questions about the α-particle optical model potential (OMP) within various mass ranges, i.e., for 64Zn, 108Cd, 113,115In, 121,123Sb, and 191,193Ir target nuclei. Purpose: The accuracy as well as eventual uncertainties and/or systematic errors of using a previous optical potential are much better considered by analysis of such accurate data. Method: Statistical model (SM) calculations of the (α,x) reaction cross sections have been carried out using model parameters that were previously obtained by analyzing independent data, particularly γ-ray strength functions, and taking into account their uncertainties and questions of extrapolation for nuclei without similar data. Results: Consistent description of the recent α-induced reaction data is provided by the above-mentioned optical potential with no empirical rescaling factors of either its own parameters or the γ and/or nucleon widths. Effects of still uncertain SM parameters on calculated α-induced reaction cross sections and conclusions on the α-OMP can be now discussed due to unprecedented precision of the new data. Conclusions: The α-particle optical potential has been confirmed at incident energies below the Coulomb barrier using statistical-model parameters validated through a former analysis of independent data. [ABSTRACT FROM AUTHOR]

Background: Challenging questions of the α-particle optical-model potential (OMP) are still pointed out by recent high-precision measurements of α-induced reaction data below the Coulomb barrier. Moreover, the reliability of a previous OMP for α particles on nuclei within the mass number range 45≤A≤209 has been recently proved for emitted α particles as well, but only in the case of proton-induced reactions on Zn isotopes [Phys. Rev. C 91, 064611 (2015) (Paper I)]. Purpose: Analysis of most recent (α,γ) reaction data for Ge and Zr isotopes, which provides an additional validation of the above-mentioned potential, is related to a further account of α-particle emission in neutron-induced reactions on Zr isotopes, at the same time with a suitable description of all competitive processes. Methods: A consistent parameter set, established or validated by independent analysis of recent various data, particularly γ-ray strength functions, has been involved within model calculation of the (α,γ) as well as (n,α) reaction cross sections. The latter are part of the whole analysis of the neutron activation of Zr isotopes, in order to avoid any error compensation or latent ambiguity. Results: The aforesaid potential provides a consistent description of recent α-induced reaction data with no empirical rescaling factors of the γ and/or nucleon widths. On the other hand, its use leads to underestimated predictions of the pre-equilibrium emission and statistical models for the (n,α) reaction cross sections. Conclusions: An optical potential with a volume imaginary component seems to be needed to describe the low-energy α-particle evaporation, while only surface absorption occurs in α-induced reactions at similar 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: 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]

This paper presents an overview of the activities of the European Consortium on Nuclear Data Development and Analysis for Fusion. The Consortium combines available European expertise to provide services for the generation, maintenance, and validation of nuclear data evaluations and data files relevant for ITER, IFMIF and DEMO, as well as codes and software tools required for related nuclear calculations. [ABSTRACT FROM AUTHOR]

Following the EUROfusion PPPT-programme action for an advanced modeling approach of deuteron-induced reaction cross sections, as well as specific data evaluations in addition of the TENDL files, an assessment of the details and corresponding outcome for the latter option of TALYS for the breakup model has been carried out. The breakup enhancement obtained in the meantime within computer code TALYS, by using the evaluated nucleon-induced reaction data of TENDL-2019, is particularly concerned. Discussion of the corresponding results, for deuteron-induced reactions on 58 Ni, 96 Zr, and 231 Pa target nuclei up to 200 MeV incident energy, includes limitations still existing with reference to the direct-reaction account. [ABSTRACT FROM AUTHOR]

Within the double folding formalism of the α-nucleus optical potential, used previously for a semi-microscopic analysis of the α-particle elastic scattering on A ~ 100 nuclei at energies below 32 MeV, effects due to changes of the nuclear density at a finite temperature are considered. Parameterizations of the double-folding (DF) real potential as well as of a regional phenomenological potential have been used in the study of the (n, α) reaction cross sections for the target nuclei 92,95,98,100Mo. Taking into account the microscopic DF potentials based on nuclear density distributions, we are able to fully describe the excitation functions of the (n, α) reactions. It is shown that the temperature dependence of the nuclear density distribution function can be an important aspect that has to be included in statistical model calculations even for a nuclear temperature smaller than 2 MeV. [Copyright &y& Elsevier]

Abstract The role of nuclear data for neutronics analyses of Fusion Technology (FT) facilities is presented in this paper. Nuclear data evaluations of high quality are required for transport simulations, uncertainty assessments, activation and radiation damage calculations affecting the design and performance of the FT facilities, as well as safety, licensing, waste management and decommissioning issues. A corresponding programme on the nuclear data development (NDD) and qualification is conducted within the Power Plant Physics and Technology (PPPT) programme of EUROfusion supporting the development of the DEMO fusion power plant and the IFMIF-DONES neutron source. The programme builds on the achievements of pre-ceding NDD activities within the European fusion programme as addressed in the paper. Further needs for design, shielding, activation and radiation dose calculations are discussed, and recommendations are given to further improve and qualify the nuclear data base for PPPT nuclear analyses. This includes dedicated experimental activities tailored to the needs of DEMO and IFMIF-DONES. [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: A previously derived semi-microscopic analysis based on the Double Folding Model, for -particle elastic scattering on nuclei at energies below 32MeV, is extended to medium mass nuclei and energies from ∼13 to 50MeV. The energy-dependent phenomenological imaginary part for this semi-microscopic optical model potential was obtained including the dispersive correction to the microscopic real potential, and used within a concurrent phenomenological analysis of the same data basis. A regional parameter set for low-energy -particles entirely based on elastic scattering data analysis was also obtained for nuclei within the above mentioned mass and energy ranges. Then, an ultimate assessment of , , and reaction cross sections considered target nuclei from 45Sc to 118Sn and incident energies below ∼12MeV. The former diffuseness of the real part of optical potential as well as the surface imaginary potential depth have been found to be responsible for the actual difficulties in the description of these data, and modified in order to obtain an optical potential which describes equally well both the low-energy elastic scattering and induced reaction data for -particles. [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 experimental cross sections for all neutron-induced reactions on the stable isotopes of Mn and Cu at incident energies up to 40 MeV are compared with results of pre-equilibrium (PE) and statistical model calculations. Taking advantage of the large sensitivity of statistical model analysis to residual nuclei parameters, for energies up to 20 MeV, our work was then focused on assessing PE model assumptions by data analysis in the energy range 20–40 MeV. The PE model reliance on the nuclear potential finite-depth correction for description of particle–hole state densities (PSD), nuclear-shell effects within the PSD formula, and single-particle level density is thus discussed with regard to the whole data basis. The related variance of the model results has been found as large as the differences between the global and local model calculations, while the data basis available between 20 and 40 MeV for the Mn and Cu isotopes is however too scarce in this respect. [Copyright &y& Elsevier]

Abstract: An analysis of the elastic scattering of deuterons on 6,7Li, for energies up to 50 MeV, has been carried out by using a phenomenological optical potential. Energy-dependent average parameters of the optical model potential have been obtained in the analysis of the corresponding real and imaginary volume integrals, pointing out an “anomalous” behavior of the real potential when the imaginary part approaches zero. This could be a consequence of the dispersion relations, but may be also related to the non-locality of the basic real potential term which introduces a slow and smooth energy dependence. On the other hand, the coupled reaction channels method has been used in order to describe the experimental angular distributions including the backward hemisphere at 14.7 and 19.6 MeV but not at 50 MeV. The comparison between the experimental and calculated elastic scattering angular distributions proves the reliability of the present average optical potentials, at variance with the extrapolation of the deuteron global potentials to other mass and energy domains. [Copyright &y& Elsevier]

The double-folding formalism of the α-nucleus optical potential is used and appropriate effective nucleon–nucleon (NN) interaction and α-particle density distribution at low energies are obtained by analysis of the α–α elastic-scattering at energies below 35 MeV. Next a semi-microscopic analysis based on the Double Folding Model (DFM) for the α-particle elastic scattering on A∼100 nuclei at energies below 32 MeV has been carried out. The energy-dependent phenomenological imaginary part for this semi-microscopic optical model potential (OMP) was obtained, making use also of the dispersive correction to the microscopic real potential. This imaginary potential has then been introduced within a complete phenomenological analysis of the same data basis. A regional parameter set of the phenomenological OMP for low-energy α-particles has thus been obtained for nuclei in the mass range A∼100, which is of interest to basic nuclear physics as well as nuclear technology. [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]

Taking elastic scattering of [sup 6,8]He on protons as an example, it is shown that the differences between density distributions coming from different models can be evaluated when scattering data of the nuclei involved are available for comparison. Microscopic elasticscattering angular distributions have been calculated for incident energies <100A MeV by using the Tanihata and COSMA models for the density distributions of He nuclei, the M3Y-Paris effective NN interaction, and the Bray et al. imaginary part of the optical potential. The present microscopic angular distributions based on the Tanihata densities are in good agreement with the available experimental data and also similar to results of other theoretical calculations, showing the sensitivity of scattering to the density distributions of these helium isotopes. [ABSTRACT FROM AUTHOR]

The cross sections of the 59Co(d,p) 60m,gCo, 51V (d,p) 52V, and natV (d,xn)51 Cr reactions were accurately measured at the Soreq Applied Research Accelerator Facility in the energy range 2.7-5.4 MeV. The obtained results together with other data, available in the same region of the nuclear chart, were used for verifying the theoretical models. The consistent theoretical model calculation successfully reproduces the experimental results. [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]

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]