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The Extreme Light Infrastructure is a major European undertaking with the aim of constructing a set of facilities that can produce the worlds highest intensity laser beams as well as unique high-brilliance, narrowbandwidth gamma-ray beams using laser-based inverse Compton scattering. The latter will be one of the unique features of the facility in Bucharest- Magurele, Romania, where the scientific focus will be towards nuclear physics and nuclear photonics both with high intensity lasers and gamma beams individually, as well as combined. One of the main instruments being constructed for the nuclear physics and applications with high-brilliance gamma-beams research activity is the ELIADE -ray detector array. This array consists of eight segmented HPGe clover detectors as well as largevolume LaBr3 detectors. The nuclear physics topics are expected to cover a large range including, but not limited to, properties of pygmy resonance and collective scissors mode excitations, parity violation in nuclear excitations, and matrix elements for neutrinoless double-beta decay. However, the uniqueness of the environment in which ELIADE will operate presents several challenges in the design and construction of the array. Here, we discuss some of these challenges and how we plan to overcome them, as well as the current status of implementation. [ABSTRACT FROM AUTHOR]

The structure of the 131Sn nucleus was studied at the Institut Laue-Langevin by prompt-delayed -ray spectroscopy across the 0.3 μs, 23/2-isomeric state at 4670 keV, following cold-neutron-induced fission of 235U and 241Pu targets. New -ray transitions are observed and the results are compared with theoretical calculations performed with the Hybrid Configuration Mixing Model. The latter suggests that the majority of the states can be well-described in terms of couplings between single-hole degrees of freedom and 132Sn core excitations, pointing to a robust neutron shell closure at N = 82. [ABSTRACT FROM AUTHOR]

The low-spin structure of the 41Ca isotope, populated by neutron capture, has been investigated by high resolution -spectroscopy techniques. The experiment was performed at the PF1B cold neutron facility at the Institut Laue-Langevin (Grenoble, France) employing the EXILL array, consisting of 46 HPGe crystals. Several new γ rays have been observed and two excited states were newly established. [ABSTRACT FROM AUTHOR]

The γ decay of the one-proton valence nucleus 133Sb is studied using the cold-neutron induced fission of 235U and 241Pu targets. The experiment is performed at the ILL reactor in Grenoble, using a highly efficient HPGe array, also coupled to fast LaBr3(Ce) scintillators. High-spin excited states above the 16.6 μs isomer are observed, and the lifetime of the 13/2+ and 15/2+ states is measured by fast-timing techniques, revealing a complex nature of the wave functions. The experimental results are well-interpreted by a newly developed microscopic model which takes into account the coupling between the valence proton and excitations (both collective and noncollective) of the doubly magic 132Sn core. [ABSTRACT FROM AUTHOR]

High- and medium-spin structures have been investigated in neutronrich 96Y isotope produced in the cold-neutron-induced fission of 235U and 241Pu targets. The study significantly extended the existing level scheme of this isotope. In the current work, particular attention was devoted to the structure which has been identified above the long 9.6 s, (8+) isomer, up to the excitation energy of 4813 keV. The angular correlation analysis, together with obtained decay pattern, allowed to propose spin values for some of the newly observed states. [ABSTRACT FROM AUTHOR]

Medium-spin, yrast excitations in nucleus 83As have been studied in neutron-induced fission of 235U. The experiment took place at the Institut Laue-Langevin in Grenoble where gamma rays were registered using the EXILL detector array. Recently, we proposed new tentative (9/2+) spin assignment for 2777 keV level in 83As, which is now discussed in the context of deformation showing up in 78Ni region. [ABSTRACT FROM AUTHOR]

Extreme Light Infrastructure--Nuclear Physics (ELI-NP) is one of the three pillars of the pan-European ELI initiative aiming to use extreme electromagnetic fields for nuclear physics research. The pillar, currently under construction at Bucharest-Magurele, will comprise two major research instruments: a high power laser system and a very brilliant gamma beam system. Both systems are at the limits of the present-day's technology. The high power laser system will consist of two 10 PW APPOLON-type lasers based on OPCPA technology with output energy higher than 200 J, pulse duration of 20-30 fs and intensities of up to 1023-1024 W/cm². The gamma beam, produced via inverse Compton scattering of laser pulses on a relativistic electron beam, will be characterized by high spectral density of about 104 photons/s/eV, narrow bandwidth (< 0:5%), tunable energy of up to 20 MeV and degree of linear polarization higher than 95%. [ABSTRACT FROM AUTHOR]

The 40Ar + 208Pb multinucleon transfer reaction has been studied at Elab = 255 MeV with the large solid angle magnetic spectrometer PRISMA. Mass and charge yields, differential and total cross sections, total kinetic energy loss distributions of different channels were simultaneously measured. Angular distributions were measured in a wide angular range by matching different spectrometer angular settings. Absolute cross sections were obtained by careful evaluation of the spectrometer response function. These cross sections for different transfer channels allow the discussion of the role played by nucleon-nucleon correlations. [ABSTRACT FROM AUTHOR]

Lifetimes of high-spin states in As have been measured using Doppler shift attenuation technique with the GASP and RFD set-up. The nucleus of interest was populated in the 40Ca(32S, 3p) 69As reaction at beam energy of 95 MeV. Extracted lifetimes for the 33/2+ state at 7897 keV and 37/2+ state at 9820 keV are 72 (-45, +55) fs and 25(-25, +50) fs, respectively. The transition quadrupole moment resulting from the measurement can serve as a test of the TRS calculations. [ABSTRACT FROM AUTHOR]

Lifetimes of high-spin states in 66Ge have been measured using Doppler shift attenuation technique with the GASP and RFD setup. The 66Ge nucleus was populated in the 40Ca(32S, α2p) reaction at beam energy of 95 MeV. The transition quadrupole moment, Qt, of the negative parity band in this nucleus has been determined to be approx. 0.9γ 0.1 eb. [ABSTRACT FROM AUTHOR]

The revival of transfer reaction studies benefited from the construction of the new generation large solid angle spectrometers, coupled to large γ arrays. The recent results of -particle coincident measurements in 40Ca+96Zr and 40Ar+208Pb reactions demonstrate a strong interplay between single-particle and collective degrees of freedom that is pertinent to the reaction dynamics. The development of collectivity has been followed in odd Ar isotopes populated in the 40Ar+208Pb reaction through the excitation of the 11/2- states, understood as the coupling of single particle degrees of freedom to nuclear vibration quanta. Pair transfer modes is another important degree of freedom which is presently being studied with Prisma in inverse kinematics at energies far below the Coulomb barrier. First results from the 96Zr+40Ca reaction elucidate the role played by nucleon-nucleon correlation. [ABSTRACT FROM AUTHOR]

The Recoil Distance Doppler-Shift method has been used to measure the lifetime of the first 3- state in the N = Z 44Ti nucleus, populated via the 40Ca(6Li, pn)44Ti reaction. State-of-the-art analysis techniques have been employed to determine the experimental lifetime, resulting in a B(Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed.) ≈ 3 W.u. [ABSTRACT FROM AUTHOR]

We present results from two recent runs which illustrate the performance of the PRISMA spectrometer in the proximity of the upper limit of its operational interval, namely 96Zr+124Sn at Elab = 500 MeV and 136Xe+208Pb at Elab = 930 MeV. In the latter run, the γ array CLARA also allowed us to identify previously unknown γ transitions in the nuclides 136Cs and 134I. [ABSTRACT FROM AUTHOR]

The large solid angle magnetic spectrometer PRISMA coupled to the γ array CLARA represents a significant step forward in the field of binary reactions at energies close to the Coulomb barrier. With this set-up extensive investigations have been carried out for nuclear structure and reaction dynamics. Via γ-particle coincidences it is now experimentally possible to measure the transfer strength to specific final states with high efficiency. In reactions with heavy ions, one can populate states of high angular momentum and, at the same, one can probe the population of specific nuclear levels via transfer of multiple pairs. Valuable information about the structure of those states can be then derived from the study of their decay modes. In the present paper aspects of these studies will be presented, focusing more closely on the reaction mechanism, in particular on the properties of quasielastic and deep-inelastic processes and on nucleon-nucleon correlations at energies far below the Coulomb barrier. We concentrated on (near) closed shell systems as they allow a better quantitative comparison between experiment and theory. [ABSTRACT FROM AUTHOR]

The quadrupole interaction of the 11- and 12+ isomers in 192,194Pb nuclei has been investigated in the electric field gradient of metallic Bi polycrystalline lattice by the method of time-differential observation of the γ-rays perturbed angular distribution. The electric field gradient strength of the host Bi lattice has been calibrated by using as probe the 12+ isomer in 194Pb. The intrinsic quadrupole moments derived for the 11- isomers described by the π(1h9/21i13/2) intruder configuration are compared with the predictions of mean-field and interacting boson models. [ABSTRACT FROM AUTHOR]