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The systematics of the experimental data of alpha-decay fine structure in the even-even nuclei above lead are examined. The representation of relative branching ratios (b.r.) and hindrance factors (HF) for the 2+1, 4+1, and 6+1 states within the valence correlation schemes (as a function of NpNn or P = NpNn/(Np + Nn)) proves useful, as it provides smooth trajectories that can be discussed in parallel with the development of collectivity. It is shown that practically all recent theoretical calculations are not able to account for some of the most conspicuous features presented by the evolution of the branching ratios and hindrance factors. These are: a practically exponential increase of the b.r.'s and HF's for the 2+1 state of collective nuclei (above P 4.0); a pronounced maximum around P 7.5 of the same quantities for the 4+1 state, a region where these nuclei have usually been considered as well deformed rotors; and the decrease of these quantities for the 6+1 state in the interval of P from 4.0 to about 8.0. The observed evolutions of these fine structure quantities do not appear to be correlated with different structure indicators deduced from the low-lying level schemes, with the exception of the HF of the 2+ state which is reasonably well correlated with a parameter that describes the nuclear rigidity, indicating the necessity of going beyond the rigid rotor description of the nuclei considered in this study. It is also necessary that a simultaneous description of both electromagnetic transitions and alpha decay fine structure data is achieved by the theoretical calculations.

This proceedings volume contains the invited lectures and contributions presented at the International Summer School on Nuclear Physics held at Trei Brazi, a summer resort of the Bioterra University, near the city of Predeal, Romania, on 9–20 July 2012. The long tradition of International Summer Schools on Nuclear Physics in Romania dates as far back as 1964, with the event being scheduled every two years. During this period of almost 50 years, many outstanding nuclear scientists have lectured on various topics related to nuclear physics and particle physics. This year we celebrate the 80th birthday of Aureliu Sandulescu, one of the founders of the Romanian school of theoretical nuclear physics. He was Serban Titeica's PhD student, one of Werner Heisenberg's PhD students, and he organized the first edition of this event. Aureliu Sandulescu's major contributions to the field of theoretical nuclear physics are related in particular to the prediction of cluster radioactivity, the physics of open quantum systems and the innovative technique of detecting superheavy nuclei using the double magic projectile 48Ca (Calcium), nowadays a widely used method at the JINR—Dubna and GSI—Darmstadt laboratories. The title of the event, 'Dynamics of Open Nuclear Systems', is in recognition of Aureliu Sandulescu's great personality. The lectures were attended by Romanian and foreign Master and PhD students and young researchers in nuclear physics. About 25 reputable professors and researchers in nuclear physics delivered lectures during this period. According to a well-established tradition, an interval of two hours was allotted for each lecture (including discussions). Therefore we kept a balance between the school and conference format. Two lectures were held during the morning and afternoon sessions. After lecture sessions, three or four oral contributions were given by young scientists. This was a good opportunity for them to present the results of their research in front of renowned professors and researchers in nuclear physics. This proceedings volume is organized into four chapters, which reflects the traditional chapter structure of nuclear physics textbooks, but seen from the perspective of open quantum systems: INuclear structure IIDecay processes IIINuclear reactions and astrophysics IVContributions The lectures and contributions are listed alphabetically by author within each chapter. The volume contains many comprehensive reviews related to the topics of the School. The first week of the School was focused on nuclear structure and decay phenomena, considering the nucleus as an open system. Experts in these fields lectured on cluster radioactivity, the stability of superheavy nuclei, alpha-decay fine structure, fission versus fusion, beta and double beta decay and pairing versus alpha-clustering. New experimental results related to the nuclear stability of low-lying and high spin states were also presented. Recent developments at JINR—Dubna and GSI—Darmstadt international laboratories were also reported by their current or former directors. The second week of the event was dedicated to the physics of exotic nuclei, heavy ion reactions and multi-fragmentation, symmetries and phase transitions of open quantum systems. The stability of the atomic nucleus is an important and always interesting discussion point, especially in the context of newly discovered nuclear systems close to the stability line, such as proton/neutron rich or superheavy nuclei. Several lectures and contributions were focused on nuclear structure models describing low-lying states. This includes the status of density functional theory, new developments in Bohr–Mottelsohn Hamiltonian and shell-model theory, proton–neutron correlations, shape coexistence, back-bending phenomena and the thermodynamics of open quantum systems. Open systems in astrophysics, such as supernovae and neutron stars, were presented in detail by several lecturers. Important topics connected to the status of the equation of state, hyperonic and quark matter and neutrino physics, as well as the applications of nuclear structure in astrophysics, were also on the School's agenda. There were many discussions and questions both during and after presentations. An open and friendly atmosphere characterized our School, although different opinions quite often divided the participants. Many discussions continued during coffee breaks and excursions organized in the beautiful surroundings. We hope that this proceedings volume will be useful for future reference to both young scientists and senior researchers working in various fields of nuclear physics. We cannot end without expressing our many thanks to the National Authority for Scientific Research and the Romanian Academy (Elias Foundation) for their financial support. We acknowledge the Horia Hulubei National Institute of Physics and Nuclear Engineering and Bioterra University for their important contribution in organizing the School. Guest Editors D S Delion, N V Zamfir, A R Raduta and F Gulminelli International Summer School on Nuclear Physics: First Week International Summer School on Nuclear Physics: Second Week Sponsors

The 2+2 state in 132Te is identified as the one-phonon MSS in a projectile Coulomb excitation experiment presenting a firm example of a MSS in unstable, neutron rich nuclei. The results of shell-model calculations based on the low-momentum interaction Vlow−k are in good agreement with experiment demonstrating, the ability of the effective shell-model interaction to produce states of mixed symmetry character.

The Extreme Light Infrastructure - Nuclear Physics facility (ELI-NP) to be constructed in Bucharest-Magurele will be one of the three pillars of ELI and will consist of two components: a very high intensity laser beam and a very intense (1013 γ/s), brilliant γ beam, 0.1% bandwidth, with Eγ = 19 MeV. ELI-NP will allow either combined experiments between the high-power laser and the γ beam or stand-alone experiments. This facility will create a new European laboratory with a broad range of science covering frontier fundamental physics, new nuclear physics and astrophysics as well as applications. A review of the Project and the Status of its implementation will be presented.

The 2+2 state in 132Te is identified as the one-phonon MSS in a projectile Coulomb excitation experiment presenting a firm example of a MSS in unstable, neutron rich nuclei. The results of shell-model calculations based on the low-momentum interaction Vlow-k are in good agreement with experiment demonstrating the ability of the effective shell-model interaction to produce states of mixed-symmetry character.

The parity doublet of 1+/1− states of Ne-20 at 11.26 MeV excitation energy is one of the best known test cases to study the weak part of the nuclear Hamiltonian. The feasibility of parity violation experiments depend on the effective nuclear enhancement factor (RN/|E(1+) − E(l−)|) which amplifies the impact of the matrix element of the weak interaction on observables indicating parity mixing. An extreme large value of Rn/|E(1+) − E(l−)| = (670 ± 7000) MeV−1 was reported for the doublet in 20Ne. The large uncertainty depends amongst others on the large uncertainty of |E(1+) − E(l−)| = 7.7±5.5 keV of the parity doublet. Nuclear resonance fluorescence (NRF) experiments with linearly and circularly polarized photon beams were performed at the High Intensity Gamma-Ray Source at Duke University, Durham, NC, USA, to determine the energy difference of the parity doublet with higher precision. The different angular distributions for 0+ → 1− → 0+ and 0+ → 1+ → 0+ NRF cascades in polarized γ-ray beams were used to determine the energy difference of the parity doublet to 2.9(13) keV.