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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.
It is possible to excite atomic nuclei electromagnetically and even separate proton or neutron from a sample which is exposed to gamma rays by a clinical linac. Thus, the determination of the ...elemental concentration of a sample by photo-activation analysis is a reasonable attempt since it is related to the detailed analysis of the photonuclear reaction of an intended element. In this study, in order to get the proof of principle for photo-activation a titanium dioxide and a 10 kurus Turkish coin samples are irradiated with high energy bremsstrahlung photons at the end-point energy of 18 MeV and their zinc and copper concentrations are determined by a precise measurement with a high purity germanium detector.
Two new gamma spectrometer projects are under development, both with some challenging technical characteristics in common, one for the investigation of weakly bound nuclear beam reactions at near ...barrier energies, and the other for the measurement of double charge exchange reactions in the 15-70 MeV per nucleon range. The first one is being developed and tested at the IFUSP, and the other is going to be built and installed at the LNS, INFN, under the NUMEN collaboration. The main characteristics of the two projects are presented and discussed.
The bremsstrahlung photons of 18MeV end-point energy produced by a clinical linear accelerator were used to irradiate (93)Nb, producing (92m)Nb via the photonuclear reaction. The gamma-ray spectrum ...emitted by the excited nucleus was measured with high purity germanium detector. For analysis of the energy transitions, both gf3 and ROOT spectrum analysis programs were applied. The results were shown to be comparable with the literature values, demonstrating the ability to use a clinical liner accelerator in nuclear physics measurements.
We have run an experiment to determine the energy levels and half-lives of Gallium nucleus by using the photonuclear reactions with end-point energy of 18 MeV bremsstrahlung photons, produced by a ...clinical linear accelerator. As a result of 71Ga(y,n)70Ga and 69Ga(Y,n)68Ga photonuclear reactions, the energy levels and half-lives of 70Ga and 68Ga nuclei have been determined. The results are in good agreement with the literature values.
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