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A heuristic “3 -dimens ional” project is presented, accomplished by the 24 post- graduate students of our Department’s MSc. Course “Advanced Biomedical Technology”. The project has addressed, first, RT innovative Technology as reflected on Industrial Property (IP) docs, second, cardinal patient-care and medical-managerial aspects and finally, their combination with relevant Medical Protocols, Guidelines & Standards. Parts of the three modules of the 4 th - trimester, i.e. “Large Therapeutic and Diagnostic Facilities Safety, Radiation Protection and Quality Assurance” ( PMS_BIT_2.4. ), “Biomedical Technology (BMT) of Home-Surveillance, Health- Care Management and Online Health Services” ( PMS_BIT_2.5.) and “BMT -Quality Assurance, Industrial Property Rights, Technical Standards and Medical Protocols and Guidelines” ( PMS_BIT_2.6.), taught by the first author, have been combined and each student has prepared and orally presented a “3 - D” paper. Around 1000 pages of relevant content (over 1 GB) with numerous Figures and Tables are included in the produced Compendium. The quality of the students’ papers and presentations corroborate the need of introducing novel, contemporary and creative examination methods, attracting their interest and promoting their self-confidence.

This paper presents the peak-to-background ratio improvement, which can be achieved in PIXE and XRF applications by the use of thin crystal detectors. This improvement becomes apparent in the presence of an intense γ-ray source, which can be produced either after proton irradiation of a sample (PIXE), or after the deexcitation of the radionuclide in Radioisotope induced XRF analysis (RIXRF). In order to study theoretically the energy response of a silicon crystal in the X-ray energy region with respect to its thickness and the energy of the incident yradiation, a Monte-Carlo simulation was performed. Experimentally, two detectors having crystal thickness of 300 urn and 3 mm respectively were employed in specific analytical applications of PIXE, PIXE induced XRF and RIXRF techniques. The peak-to-background ratios obtained for various characteristic X-rays were compared between the two detectors. The performance of the two detectors was also compared in monochromatic XRF analysis of samples with low average atomic number matrix content.

Many nuclear astrophysics applications involve radiative α-particle captures, α decays and Qi-particle transfer reactions. Theoretical estimates of the corresponding reaction rates within the framework of the statistical model of Hauser-Feshbach remain highly uncertain due to the poor knowledge of the α-nucleus optical model potential, especially at low energies far below the Coulomb barrier. In the present paper we propose new global α-optical potentials that take into account the strong energy dependence and nuclear structure effects that characterize the alpha-nucleus interaction. The real part of the potential is calculated using a double-folding procedure over the M3KY effective nucleon-nucleon interaction. A Woods-Saxon potential is used for the imaginary potential where now a new parametrization is introduced to describe its energy dependence. Three potentials are developed, one with purely volume absorption, one with volume plus surface absorption, and finally, one where in addition to volume and surface absorption, the dispersive contributions obtained from the dispersive relation are included. The three potentials considered are able to reproduce the bulk of experimental data on (a,7), (α,η), (a,p) and (η,α) reactions as well as the existing elastic scattering data at energies of relevance to astrophysical applications. However, when considering reaction rates for nuclei in the experimentally unexplored mass region, deviations within a factor of 10 are found. These uncertainties are mainly due to the difficulty in constraining the diffuseness of the imaginary potential from analyses of existing experimental data

This paper shows that ultrastrong magnetic fields (such as those of magnetars) and dense astrophysical plasmas can reduce the half life of alpha decaying nuclei by many orders of magnitude. In such environments the conventional Geiger-Nuttall law is modifed so that all relevant half lives are shifted to dramatically lower values.

This paper summarizes the results of a series of experimental studies of mag­netic rotation in mid-shell Pb nuclei. The focus is for the 29/2- v(1i^3/2)^{-1} (x) π(3s1/2)^{-2}(1h9/2)(i13/2) magnetic band in 193Pb, for which all experimental observables have been measured. This provides a stringent test of the theoretical models aiming at the description of such excitations. These studies have been carried out in col­ laboration with different research teams from the Balkans and are an example how to utilize most efficiently the huge scientific potential of the region.

The development of autonomous measuring systems for radioactivity in the ma- rine environment is today of important scientific priority for the marine sciences and especially for the Operational Oceanography. This paper concentrates on the improvement and application of an existing Nal-based gamma ray detection system for radioactivity measurements in seawater. The set up of the system will be described together with the appropriate calibrations in the laboratory. The operation of the system in the Aegean Sea provides the monitoring efficiency at 1461 keV by intercalibration with an appropriate salinity sensor mounted close to the Nal-detector. The gross counting rate was found constant within the statistical uncertainty of the measurements, during dry periods. The artificial radioactivity (137Cs) in the North Aegean Sea was increased, however, up to seven times after strong rainfall, compared to the mean radiation level as given in literature. This increment remains only for a short period of time (~2 days), due to strong advection processes of the water masses during strong rainfall.

The ossendorf Ion Beam Laboratory has been developed to an international large scale user facility in the field of ion beam physics and ion beam materials research. The laboratory operates a large number of modern experimental equipment at three MeV accelerators, three implanters, an ECR source and a FIB which together pro- vide almost all ions species in a wide energy range from a few hundred eV to a few ten MeV. Also IBAD and PHI devices were installed for various purposes. The re- search stations at the accelerators are supplemented by complementary techniques like TEM, SEM, AUGER, AFM etc., all contributing useful information to thin film investigations. In this paper a short overview of the laboratory is given and a few recent experiments and their results are shown. Rutherford Backscattering Spec- trometry ( RBS) and Elastic Recoil Detection Analysis (ERDA) are well established techniques for quantitative thin film. The advantage of these methods consists in the simple physics they are basing on, namely the stopping of energetic ions in matter and the binary scattering of at the Coulomb potential of atomic nuclei. The increasing importance of ultra-thin layers for novel technologies demands quantita- tive analysis techniques with a depth resolution of atomic monolayers, which can be obtained for RBS and ERDA by magnetic spectrometers only. The magnetic spec- trometers we have installed at the 3 MV Tandetron and at the 5 MV tandem are described , recent applications are shown and a few problems to achieve high depth resolution will be discussed. Heavy ion detectors as Bragg IC, dE-Erest-telescopes and ToF spectrometers, developed for nuclear physics experiments, are now applied for ERDA, providing an efficient analysis of thin films containing light elements. The lateral position resolution of such detectors enables kinematic corrections and allows large solid angles. Thus by ERDA in situ studies during surface modification processes are possible like in the case of the nitridation of aluminum and stainless steel. At the external beam mainly objects of fine arts or of historical value are analysed. It will be shown, how the complementary application of PIXE, RBS and PIGE can help to detect the beginning corrosion of mediaeval glass objects.

Nuclear reaction rates play a crucial role in nuclear astrophysics. In the last decades there has been an enormous effort to measure reaction cross sections and extensive experimental databases have been compiled as a result. In spite of these efforts, most nuclear reaction network calculations still have to rely on theoretical predic- tions of experimentally unknown rates. In particular, in astrophysics applications such as the s-, r- and p-process nucleosynthesis involving a large number of nuclei and nuclear reactions (thousands). Moreover, most of the ingredients of the cal- culations of reaction rates have to be extrapolated to energy and/or mass regions that cannot be explored experimentally. For this reason it is important to develop global microscopic or semi-microscopic models of nuclear properties that give an accurate description of existing data and are reliable for predictions far away from the stability line. The need for more microscopic input parameters has led to new devel- opments within the Hartree-Fock-Bogoliubov method, some of which are presented in this paper.

Valuable information on the correlation structure of the nuclear medium is stored in the generalized momentum distribution n(p,Q), the Fourier transform of the half-diagonal two-body density matrix ρ_{2η}(r_1,r_2,r'). In this paper, we present a numerical calculation of n(p,Q) for two Jastrow-correlated models of symmetrical nuclear matter based on the structural decomposition of n(p,Q) derived by Ristig and Clark and on a Fermi-hypernetted-chain procedure. Results exhibit significant departures from the ideal Fermi gas case in certain kinematic domains; this behaviour indicates the strong short-range correlations present in these models. Nevertheless, such deviations are less prominent than in earlier low- cluster-order calculations. The results are also used to judge the quality of Silver's approximation for n(p,Q).

Measurements of Rn concentration in air indoors in Patras area, Greece, have been carried out and are presented in this paper. The method used is based on George method using activated Carbon which adsorbs Rn and a Nal (TI) γ-ray detector. The method determines the γ-ray activity of the Rn decay products. The Rn level in (pCi/l) and the total error are presented for different geological areas in the region.

The conventional tacit assumption that nuclear and sub-nuclear reactions take place in the Newtonian universal time is replaced in the present paper by a time topological space based on the interaction proper time neighbourhood. It is developed and used to solve a problem related to the nuclear reaction theory, the quantum measurement problem. The time topology is disconnected and satisfies the separation axioms of the topological space 3 , . In this topology the V+R Penrose dynamics is implemented by means of a time evolution operator,"?/ .constructed using a quantized version of CSel'fand's theory - the generalized random quantum field theory (QRQFT). As an application the quantum measurement problem solution is presented.

Radiation Protection in major research-facilities includes several aspects concerning their planning, the hazard-sources, the environmental protection and the general safety. The present paper includes a concise presentation of the approach to the radiation protection policies proposed for the Athens Race Track Microtron (250 MeV, 550 mA) and the Heraclion Modified Betatron Accelerator (25 MeV, 1 kA).

The Positron Annihilation Lifetime Spectroscopy (PALS) is a valuable method for the study of the open volume defects in materials. The reduced electron density at the vacant/defect site increases the positron lifetime, and positron lifetime increases as the size of defect increases. In the current paper the experimental apparatus for the measurement of the positron lifetime in materials is described and the spectra from W and Cd specimens are analyzed. The presence of dislocations and vacancy defects is found, since the positron lifetimes of specimens are higher than the defect-free (bulk) values.

This paper presents our recent study on the production of neutron-rich rare isotopes with heavy-ion beams in the energy region of 15 MeV/nucleon. We present calculated production cross sections of neutron-rich nuclides from collisions of a 86 Kr (15 MeV/nucleon) beam with 238 U targets. Our calculations are based on a two-step approach: the dynamical stage of the collision is described with either the phenomenological Deep-Inelastic Transfer model (DIT), or with the microscopic Constrained Molecular Dynamics model (CoMD). The de-excitation of the hot heavy projectile fragments is performed with the Statistical Multifragmentation Model (SMM). We also performed calculations with a radioactive beam of 92 Kr (15 MeV/nucleon) with a target of 238 U and observed that the multinucleon transfer mechanism leads to very neutron-rich nuclides toward and beyond the astrophysical r-process path. In the future, we plan to experimentally investigate such reactions in the KOBRA spectrometer at the RISP facility in Korea. We conclude that the reaction mechanism at beam energies below the Fermi energy involving periph- eral nucleon exchange, constitutes a novel and effective route to access extremely neutron-rich isotopes toward the r-process path and the neutron drip-line.

The intense collaborative effort for electricity generation through fusion is currently focused on the exploitation of the Joint European Torus (JET) as well as on the preparation of its successors ITER and DEMO. Within this frame, several experiments are carried out at JET aiming to study crucial aspects related to the construction and operation of ITER as well as to the design of future fusion power plants.Most important, a high-performance Deuterium-Tritium campaign is expected to take place at JET in 2020 providing unique neutron yields up to 1.7×1021 neutrons. This paper focuses on the participation of NCSRD fusion technology group in JET nuclear analysis and, in particular, on the implementation of activation experiments at JET and discusses the main achievements in the light of their significance for optimizing future fusion activities and studies.

The application of standard-less PIGE requires the a priori knowledge of the differential cross section of the reaction used for the quantification of each detected light element. Towards this end, a lot of datasets have been published the last few years from several laboratories around the world. The discrepancies often found between different measured cross sections can be resolved by applying a rigorous benchmarking procedure through the measurement of thick target yields. Such a procedure is proposed in the present paper and is applied in the case of the 19F( p, p ′ γ )19F reaction.

Fission barrier height is one of the least known nuclear parameters, with experimental data, acquired decades ago, existing only close to beta-stability line. Availability of heavy radioactive beams offers possibility to investigate fission of more exotic nuclei and using the state of the art detection technique such as the active target we can even probe their fission barriers heights with precision has not been reached so far. The present status of fission barrier measurement is going to be explained in this paper. We are going to discuss the possibilities to stage experimental studies of fission barrier heights at new generation of ISOL facilities such as HIE-ISOLDE and active target ACTAR TPC. As an example we select the experiment IS581, being prepared for execution at the HIE-ISOLDE facility (CERN).

In the first stage of this paper, we perform detailed calculations of the electron capture cross sections on nuclei under laboratory conditions. We use the nuclear method known as proton-neutron quasi-particle random phase approximation (pn-QRPA). In the second stage, we translate the above mentioned e--capture cross sections to the stellar environment. As a concrete nuclear target we use the 56Fe and the 66Zn isotopes, which belong to the iron group nuclei and play prominent role in stellar nucleosynthesis: i) in pre-supernova phase and ii) in supernova phase.