Previously measured elastic scattering and two-neutron transfer angular distributions for 8He scattered from a 4He target Phys Lett. B 75, 58-62, 2017 are analysed using the coupled reaction channels ...(CRC) formalism and the effect of 1, 2 and 4-neutron transfers on both the elastic scattering and 6He + 6He channels is examined. The CRC calculations find that 1n and 2n transfers are the dominant processes in the production of 6He while the influence on the elastic scattering of 4n transfer between the 4He cores is small. Calculated excitation functions based on fits to both data sets suggest resonant-like behaviour centred at 12Be excitation energies of about 13 MeV and 14-16 MeV, both associated with the L=2 and 4 partial waves and consistent with molecular structures in the intermediate 12Be system.
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The article describes the main achievements of the NUMEN project together with an updated and detailed overview of the related R&D activities and theoretical developments. NUMEN proposes an ...innovative technique to access the nuclear matrix elements entering the expression of the lifetime of the double beta decay by cross section measurements of heavy-ion induced Double Charge Exchange (DCE) reactions. Despite the fact that the two processes, namely neutrinoless double beta decay and DCE reactions, are triggered by the weak and strong interaction respectively, important analogies are suggested. The basic point is the coincidence of the initial and final state many-body wave functions in the two types of processes and the formal similarity of the transition operators. First experimental results obtained at the INFN-LNS laboratory for the
40
Ca(
18
O,
18
Ne)
40
Ar reaction at 270MeV give an encouraging indication on the capability of the proposed technique to access relevant quantitative information. The main experimental tools for this project are the K800 Superconducting Cyclotron and MAGNEX spectrometer. The former is used for the acceleration of the required high resolution and low emittance heavy-ion beams and the latter is the large acceptance magnetic spectrometer for the detection of the ejectiles. The use of the high-order trajectory reconstruction technique, implemented in MAGNEX, allows to reach the experimental resolution and sensitivity required for the accurate measurement of the DCE cross sections at forward angles. However, the tiny values of such cross sections and the resolution requirements demand beam intensities much larger than those manageable with the present facility. The on-going upgrade of the INFN-LNS facilities in this perspective is part of the NUMEN project and will be discussed in the article.
The angular distributions of
13
C elastically scattered by
9
Be nuclei were measured at
E
Lab
(
13
C) = 16.25 and 19.5 MeV. The measured angular distributions were analyzed via the optical model and ...the DWBA within the coupled reaction channels methods. In addition to this, the previously obtained data were reanalyzed at energies
E
Lab
= 22.75, 28.12, 36.15, 57.77 and 72.88 MeV. The aim of the study was to elucidate the role of the
α
-cluster transfer mechanism in the large-angle scattering. As a result of these calculations, the optimal parameters of the potentials and their energy dependence were obtained for
13
C+
9
Be nuclear system. The data at the backward angles are fairly well reproduced. The spectroscopic amplitudes were extracted for the
13
C
→
9
Be +
α
configuration at various energies. The results are compared with previously reported values.
Two dimensional solution of the Schrödinger equation for the Kratzer potential with and without the presence of a constant magnetic field is investigated within the framework of the asymptotic ...iteration method. The energy eigenvalues are analytically obtained for the absence of the magnetic field case. However, in the presence of a constant magnetic field, the energy eigenvalues are calculated numerically using the same method. The results obtained by using different Larmor frequencies and potential parameters are compared with the results of the absence of the magnetic field case (
ω
L
= 0). Effect of the magnetic field on the energy eigenvalues of the Kratzer potential is precisely presented.
In this study, the levels of the natural and artificial radioactivity in soil samples collected from surrounding of Karaman in Turkey were measured. Activity concentrations of the concerned ...radionuclides were determined by gamma-ray spectrometry using a high-purity germanium detector with a relative efficiency of 40 % at 1.332 MeV. The results obtained for the (238)U series ((226)Ra, (214)Pb and (214)Bi), (232)Th series ((228)Ac), (40)K and fission product (137)Cs are discussed. To evaluate the radiological hazard of radioactivity in samples, the radium equivalent activity (Raeq), the absorbed dose rate (D), the annual effective dose and the external (Hex) and internal hazard index (Hin) were calculated and presented in comparison with the data collected from different areas in the world and Turkey.
The effect of the potential well size on the spectra and B(E2) transition rates of the Z(5) solution of the Bohr Hamiltonian, corresponding to triaxial shapes, has been studied. Convergence to the ...Z(5) solution is obtained for large well sizes. The results are compared to the infinite well, the harmonic oscillator and the rigid triaxial rotor results. The relevance of this solution to the prolate to oblate shape/phase transition in neutron-rich nuclei in the W-Os-Pt region is discussed.
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