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Extreme Light Infrastructure - Nuclear Physics (ELI-NP), a new Research Center under construction, will use extreme electromagnetic fields for nuclear physics research and will be operational in 2018. The status of the Project implementation will be presented. At ELI-NP, a high power laser system together with a very brilliant gamma beam are the two main research tools. Their targeted operational parameters will be described. The related experimental set-ups will be presented, together with the main directions of the research envisioned. [ABSTRACT FROM AUTHOR]

As part of the Extreme Light pan-European research infrastructure, Extreme Light Infrastructure -- Nuclear Physics (ELI-NP) in Romania will focus on topics in Nuclear Physics, fundamental Physics and applications, based on very intense photon beams. Laser-based acceleration of electrons, protons and heavy ions is a prerequisite for a multitude of laser-driven nuclear physics experiments already proposed by the international research community. A total of six outputs of the dual-amplification chain laser system, two of 100TW, two of 1PW and two of 10PW will be employed in 5 experimental areas, with the possibility to use long and short focal lengths, gas and solid targets, reaching the whole range of laser acceleration processes. We describe the main techniques and expectations regarding the acceleration of electrons, protons and heavy nuclei at ELI-NP, and some physics cases for which these techniques play an important role in the experiments. [ABSTRACT FROM AUTHOR]

The new research facility Extreme Light Infrastructure - Nuclear Physics (ELI-NP) is under construction in Romania, on the Magurele Physics campus. Valued more than 300 Meuros the center will be operational in 2019. The research center will use a high brilliance Gamma Beam and a High-power Laser beam, with unprecedented characteristics worldwide, to investigate the interaction of very intense radiation with matter with specific focus on nuclear phenomena and their applications. The energetic particle beams and radiation produced by the 2×10 PW laser beam interacting with matter will be studied. The precisely tunable energy and excellent bandwidth of the gamma-ray beam will allow for new experimental approaches regarding nuclear astrophysics, nuclear resonance fluorescence, and applications. The experimental equipment is presented, together with the main directions of the research envisioned with special emphasizes on nuclear physics studies. [ABSTRACT FROM AUTHOR]

The Project Extreme Light Infrastructure (ELI) is part of the European Strategic Forum for Research Infrastructures (ESFRI) Roadmap. ELI will be built as a network of three complementary pillars at the frontier of laser technologies. The ELI-NP pillar (NP for Nuclear Physics) is under construction near Bucharest (Romania) and will develop a scientific program using two 10 PW lasers and a Compton back-scattering high-brilliance and intense gamma beam, a marriage of laser and accelerator technology at the frontier of knowledge. In the present paper, the technical description of the facility, the present status of the project as well as the science, applications and future perspectives will be discussed. [ABSTRACT FROM AUTHOR]

The Extreme Light Infrastructure (ELI) Pan-European initiative represents a major step forward in quest for extreme electromagnetic fields. The Extreme Light Infrastructure - Nuclear Physics (ELI-NP) laboratory is one of the three pillars of the ELI project, that aims to use such extreme electromagnetic fields for nuclear physics and quantum electrodynamics research. At ELI-NP two ten petawatt high-power laser systems together with a very brilliant narrow-width γ beam are the main research tools. Here the current status of the project and the experimental program related to nuclear research, which is under preparation at ELI-NP, are presented. [ABSTRACT FROM AUTHOR]

It is shown that the Mallmann’s energy correlations, introduced a long time ago for the ground state bands of the even-even nuclei are, in fact, universal. Various bands in all collective nuclei (even-even, odd-even, and odd-odd) obey the same systematics. This unique, universal behaviour indicates the same spin dependence of the energy of the levels and, consequently, a common structure of all collective bands. Based on the second-order anharmonic vibrator description, parameter-free recurrence relations between energy ratios are deduced. These relations can be used to predict levels of higher spins in various bands. [ABSTRACT FROM AUTHOR]

It is shown that the Mallmann’s energy ratio correlations, first time proposed 50 years ago for the ground state bands of the even-even nuclei, are universal: all band structures in collective nuclei obey the same systematics. Based on a second order anharmonic vibrator description, parameter-free recurrence relations are proposed for Mallmann-type energy ratios, which can be used to extrapolate band structures to higher spin. [ABSTRACT FROM AUTHOR]

The results from two surrogate reaction experiments using the STARS (Silicon Telescope Array for Reaction Studies) spectrometer are presented. The surrogate method involves measuring the particle and/or γ-ray decay probabilities of excited nuclei populated via a direct reaction. These probabilities can then be used to deduce neutron-induced reaction cross sections that lead to the same compound nuclei. In the first experiment STARS coupled to the GAMMASPHERE γ-ray spectrometer successfully reproduce surrogate (n,γ), (n,n′γ) and (n,2nγ) cross sections on 155,156Gd using 3He-induced reactions. In the second series of experiments an energetic deuteron beam from the ESTU tandem at the Wright Nuclear Structure Lab at Yale University was used to obtain the ratio of fission probabilities for 238U/236U and 237U/239U populated using the 236,238U(d,d′f) and 236,238U(d,pf) reactions. Results from these experiments are presented and the implications for the surrogate reaction technique are discussed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We discuss the empirical evolution of structure in the spherical-deformed phase transition region in the context of the behavior of basic structural signatures in the IBA symmetry triangle. The main signatures of a phase/shape transition are a sharp increase in R4/2 ≡ E(41+)/E(21+) and minima in E(02+) and E(2γ+). [ABSTRACT FROM AUTHOR]

The nature of the low-lying K=0[sup +] excitations in deformed nuclei has recently been the subject of intense discussion. Due to different competing modes to produce such excitations it is often difficult to interpret the data related to these excitations. Experimentally, due to the difficulty of populating such states and of detecting low intensity γ rays, studies of these modes constitute a real challenge. Two categories of experiments will be presented: high resolution γ-ray measurements with the GAMS4 spectrometer following the (n,γ) reaction at ILL Grenoble ([sup 158]Ge) and high efficiency γγ measurements following β(&Vegr;)-decay performed at WNSL ([sup 162]Dy). Evidence for phase coexistence in [sup 150]Sm (GRID method) and [sup 152]Sm (γγ following &Vegr;-decay of [sup 152]Eu) will be also presented. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The path and termination point for the rp-process above [sup 56]Ni is uncertain due to a lack of knowledge of nuclear properties, especially masses, near the proton drip line. To address this need we have begun a program to measure masses of nuclei along the rp-process pathway in the A∼60–80 region using β-γ coincidence spectroscopy. Results for [sup 71]Se are presented and a preliminary experiment for [sup 72]Br is described. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Excited states in the 240Pu nucleus have been studied by means of the (p,t) reaction using the Q3D spectrometer and the focal plane detector from Munich. The comparison between experimental angular distributions and the DWBA calculations allowed the extraction of relative two-neutron transfer strengths. These observables may reveal important information about the structure of different states. The experimental two neutron strength for the 0+2 and 0+3 states is found in good agreement with the predictions of the IBA model, confirming the double octupole nature for the 0+2 state proposed in the previous studies. [ABSTRACT FROM AUTHOR]

Preliminary lifetime values have been measured for a number of near-yrast states in the odd-A transitional nuclei 107Cd and 103Pd. The reaction used to populate the nuclei of interest was 98Mo(12C,3nxα)107Cd, 103Pd, with the beam delivered by the tandem accelerator of the Wright Nuclear Structure Laboratory at an incident beam energy of 60 MeV. Our experiment was aimed at the investigation of collective excitations built on the unnatural parity, ν h11/2 orbital, specifically by measuring the B(E2) values of decays from the excited levels built on this intrinsic structure, using the Doppler Recoil Distance Method. We report lifetimes and associated transition probabilities for decays from the 15/2- and the 19/2- states in 107Cd and the first measurement of the 15/2- state in 103Pd. These results suggest that neither a simple rotational or vibrational interpretation is sufficient to explain the observed structures. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Using the GRID method the lifetimes of twelve states belonging to four negative parity bands in [sup 168]Er were measured at the ILL. For two bands the absolute E1 transitions are compared with those obtained within the framework of the sdf IBA-1 model. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

High spin states were smdied in [SUP140]Eu in a search for evidence of chiral structure. [ABSTRACT FROM AUTHOR]