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A novel Monte Carlo technique has been developed to determine lifetimes of excited states in the tens-to-hundreds femtoseconds range in products of low-energy heavy-ion binary reactions, with complex velocity distributions. The method is based on a detailed study of Doppler-broadened γ -ray lineshapes. Its relevance is demonstrated in connection with the 18 O (7.0 MeV/u) + 181 Ta experiment, performed at GANIL with the AGATA+VAMOS+PARIS setup, to study neutron-rich O, C, N,... nuclei. Excited states in 17 O and 19 O , with known lifetimes, are used to validate the method over the ∼ 20 - 400 fs lifetime-sensitivity range. Emphasis is given to the unprecedented position resolution provided by γ -tracking arrays, which turns out to be essential for reaching the required accuracy in Doppler-shift correction. The technique is anticipated to be an important tool for lifetime investigations in exotic neutron-rich nuclei, produced with intense ISOL-type beams. [ABSTRACT FROM AUTHOR]

This article is a description of the progress of research and development in the area of massive large-scale castings - slag ladles implemented in cooperation with the Faculty of Foundry Engineering of UST in Krakow. Slag ladles are the one of the major castings that has been developed by the Krakodlew (massive castings foundry) for many years. Quality requirements are constantly increasing in relation to the slag ladles. Slag ladles are an integral tool in the logistics of enterprises in the metallurgical industry in the process of wellorganized slag management and other by-products and input materials. The need to increase the volume of slag ladles is still growing. Metallurgical production is expected to be achieved in Poland by 2022 at the level of 9.4 million Mg/year for the baseline scenario - 2016 - 9 million Mg/year. This article describes the research work carried out to date in the field of technology for the production of massive slag ladles of ductile cast iron and cast steel. [ABSTRACT FROM AUTHOR]

Excited states of 17N, 18N and 19N were investigated through the measurement of gamma rays, following their population via deep-inelastic reactions induced by an 18O beam (7 MeV/u) on a thick 181Ta target. The experimental setup comprised the AGATA+PARIS detection system, coupled to the VAMOS++ magnetic spectrometer. In the 17N nucleus, the analysis of gamma-ray transitions de-exciting two states around 4–5 MeV clearly pointed to discrepancies with the lifetime values reported in literature. Three new gamma rays were observed in 18N at the energies of 1662.3(3) keV, 2073.4(8) keV and 2300.9(8) keV, and hints for other two new transitions around 1566 keV and 1720 keV were found. In addition, a new transition with energy of 2489.7(8) keV was observed in 19N. [ABSTRACT FROM AUTHOR]

An experiment, aiming at measuring lifetimes of excited states in neutron-rich C and O isotopes, was performed at the GANIL laboratory with the use of the AGATA segmented HPGe tracking array, coupled to the PARIS scintillator array and to the VAMOS++ magnetic spectrometer. The nuclei of interest were populated in transfer and deep-inelastic processes induced by an 18O beam at 126 MeV (7.0 MeV/u) on a 181Ta target. This paper contains a brief description of a novel implementation of a Monte-Carlo technique, which allowed us to obtain excited states lifetimes in the range from tens to hundreds femtoseconds for a reaction with complex initial velocity distribution, making use of the Doppler-shift attenuation method (DSAM). As a test case, we present here the analysis for two states in 19O: 2371-keV 9/2+ and 2779-keV 7/2+, for which lifetimes of τ > 400 fs and τ = 140+50−40 fs were obtained, respectively, in agreement with literature values. This newly developed approach will be essential for short lifetimes measurements in neutron-rich systems, exploiting intense ISOL-type beams, currently under development. [ABSTRACT FROM AUTHOR]

For a few years, the medical cyclotron Proteus C-235 at the Cyclotron Centre Bronowice in Kraków, Poland has been regularly used fornuclear structure experiments. One of the ongoing studies is focused on the γ decay of collective states populated in (p,p'γ) reactions. In a recent experiment, γ decays of excited states in the energy region of the Pygmy Dipole Statesin 208Pb have been observed. Good efficiency and energy resolution provided by the PARIS clusters and LaBr3Ce scintillators facilitate a comparison of the obtained energy spectra with previous measurements of pygmy states in this nucleus. [ABSTRACT FROM AUTHOR]

A first performance test of the Coulomb excitation multipolarimetry (Coulex-multipolarimetry) method is presented. It is based on a 85 Br π p 3 / 2 → π p 1 / 2 spin-flip experiment performed as part of the PreSPEC-AGATA campaign at the GSI Helmholtzzentrum für Schwerionenforschung (GSI). Via determination of background levels around the expected 85 Br excitations as well as measured 197 Au excitations, an upper limit for the M1 transition strength of the 1 / 2 1 - → 3 / 2 g.s. - transition in 85 Br and a lower beam time limit for upcoming experimental campaigns utilizing Coulex-multipolarimetry have been inferred. The impact of the use of AGATA in its anticipated 1 π configuration on these estimates is deduced via Geant4 simulations. [ABSTRACT FROM AUTHOR]

New physics opportunities are opening up by the Advanced Gamma Tracking Array, AGATA, as it evolves to the full 4 π instrument. AGATA is a high-resolution γ -ray spectrometer, solely built from highly segmented high-purity Ge detectors, capable of measuring γ rays from a few tens of keV to beyond 10 MeV, with unprecedented efficiency, excellent position resolution for individual γ -ray interactions, and very high count-rate capability. As a travelling detector AGATA will be employed at all major current and near-future European research facilities delivering stable and radioactive ion beams. [ABSTRACT FROM AUTHOR]

Recent ab initio calculations pointed out the importance of the threebody terms of the nuclear interaction, in the description of the structure of n-rich systems. The state lifetimes in light n-rich carbon and oxygen nuclei have been predicted to be sensitive to the three-body terms and, in this context, an experiment, aiming at the measurement of these lifetimes, was performed in GANIL in July 2017 with the AGATA and PARIS arrays coupled to the VAMOS++ magnetic spectrometer. Details on the AGATA preliminary data analysis are presented. [ABSTRACT FROM AUTHOR]

An experiment aiming at measuring lifetimes of the second 2+ excited states in neutron-rich C and O isotopes was recently performed at the GANIL laboratory, in France. In these nuclei, recent ab initio calculations provide a detailed description of the nuclear excited states, predicting a strong sensitivity of the electromagnetic transition probabilities to the details of the nucleon-nucleon interactions, especially in connection with the role played by the three-body (NNN) forces. Thus, the measurement of 2+ states lifetimes in this region will be a stringent test of the importance of including the NNN forces in describing the electromagnetic properties of selected nuclear states. This contribution reports on the status of the experimental analysis for the case of lifetimes in 20O. [ABSTRACT FROM AUTHOR]

A very first experiment in the field of nuclear structure at the Cyclotron Centre Bronowice (CCB) facility in Kraków, Poland has been performed recently. The medical cyclotron IBA Proteus C-235 located at CCB produces proton beams in the energy range of 70-230 MeV, that can be used for experimental purposes as well. In the reported measurement, the energy of scattered protons at the incident beam energy of 85 MeV and emitted γrays from the excited 208Pb target were measured in coincidence. During the experiment excitations in the energy region of the Giant Quadrupole and Dipole Resonances, as well as the Pygmy Dipole States were observed. By applying different conditions on the data, spectra corresponding to decays of excited states to selected low-lying levels in 208Pb were obtained, allowing a look into the Brink-Axel hypothesis. [ABSTRACT FROM AUTHOR]

We present experimental investigation of cross sections for processes crucial in view of prompt-gamma imaging. The prompt-gamma rays were produced from an interaction of a proton beam with different phantom materials composed of carbon, oxygen and hydrogen. The used target setup allowed precise selection of the investigated depth in the phantom. We studied details of the dependence of prompt-gamma yields on beam energy, detection angle and elemental composition of irradiated phantom. The analysis was focused on the discrete transitions with the largest cross sections: 4.44 MeV in 12C and 6.13 MeV in 16O. The results are presented in form of profiles of the prompt-gamma yield as a function of depth. They are compared to calculations including different cross-section models. Obtained results are in agreement with the model exploiting cross-section data collected from the literature, but the comparison with the TALYS model shows discrepancies. In the latest experiment, special attention was paid to the shape of the distal fall-off. The width of that fall-off is directly linked to the resolution of prompt-gamma based methods of range verification. Preliminary results on the beam-energy dependence of this quantity are presented. [ABSTRACT FROM AUTHOR]

A new experimental setup to measure prompt-delayed $\gamma$ -ray coincidences from isotopically identified fission fragments, over a wide time range of 100ns-200μ s, is presented. The fission fragments were isotopically identified, on an event-by-event basis, using the VAMOS++ large acceptance spectrometer. The prompt $\gamma$ rays emitted at the target position and corresponding delayed $ \gamma$ rays emitted at the focal plane of the spectrometer were detected using, respectively, thirty two crystals of the AGATA $\gamma$ -ray tracking array and seven EXOGAM HPGe Clover detectors. Fission fragments produced in fusion and transfer-induced fission reactions, using a U beam at an energy of 6.2 MeV/u impinging on a Be target, were used to characterize and qualify the performance of the detection system. [ABSTRACT FROM AUTHOR]

Pre-equilibrium emissions affect the production of excited systems in nuclear reactions, thus modifying their properties which enter as input parameters in the comparison with statistical models. In this contribution, we discuss this subject referring to recent results from experiments performed at Legnaro National Laboratories (Italy) with the GARFIELD apparatus complemented with other detectors. [ABSTRACT FROM AUTHOR]

The γ decay from the low-lying dipole states of 140Ce excited via inelastic scattering of 17O at bombarding energy of 340 MeV was measured using the high resolution AGATA-Demonstrator array in coincidence with scattered ions detected in two segmented ΔE-E silicon detectors of the TRACE array. Particular attention is here given to the decay of the first 1- state at 3643 keV which is considered to be of two-phonon character. The gamma-gamma coincidence method was applied to select desired decay branch. No direct decay from this state was observed to 2+ and 3- phonon states which would be the proof of the pure harmonic coupling. The comparison between experimentally obtained differential cross sections and analysis with distorted wave Born approximation (DWBA) allowed to conclude that the first 1- state has a different nature than higher-lying pygmy dipole states. This was possible using the form factor obtained by folding a microscopically calculated transition density. [ABSTRACT FROM AUTHOR]

Experiment Gamma-CCB at the Cyclotron Centre Bronowice focuses on investigation of gamma emission in experimental modelling of hadron therapy, searching for manifestation of the Bragg peak in gamma spectra. Experimental program comprises a series of measurements for different energies of the beam accelerated in the cyclotron Proteus C-235, as well as for several phantom materials. The paper reports on the results of the first measurements performed at 70 MeV proton beam energy and for two target materials: graphite and polymethyl methacrylate PMMA. Two different experimental techniques were tested, resulting in differential gamma spectra or spectra integrated over whole proton penetration path in a phantom. Strong correlation of the intensity of the carbon and oxygen excitation lines with the Bragg peak position has been observed in both types of measurements, confirming potential of the method in the future application in hadron therapy. [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 Coulomb excitation experiment to study electromagnetic structure of low-lying states in 42Ca with a focus on a possible superdeformation in this nucleus was performed at the Laboratori Nazionali di Legnaro in Italy. Preliminary values of the determined quadrupole deformation parameters for both the ground state band and the presumed superdeformed band are presented. [ABSTRACT FROM AUTHOR]

Odd-parity core excited states have been identified in two close neighbors of 100Sn: 96Pd and 97Ag. This was done in an fusion-evaporation experiment, using a 58Ni beam on a 45Sc target. Even-parity core excited states in these nuclei are very well reproduced in large scale (LSSM) calculations in which particle-hole excitations are allowed with up to five g9/2 protons and neutrons across the N = Z = 50 gap, to the g9/2, d5/2, d3/2, and s½ orbitals. The odd-parity states can only be qualitatively interpreted though, employing calculations in the full fpg shell model space, but with just one particle-hole core excitation allowed. A more complete model including odd-parity orbitals is need for the description of core excited states in the region of 100Sn. [ABSTRACT FROM AUTHOR]

We have investigated nuclear fragmentation reactions of a relativistic 208Pb beam.Ten isomeric states for nuclei with A = 142-152 and Z = 62-67 were observed. Measured isomeric ratios were compared, together with values from other experiments, with prediction of theoretical models. The discrepancies between the experimental and theoretical values were discussed in terms of transitions by-passing the isomer that are not included in the models. [ABSTRACT FROM AUTHOR]

The poorly known B(E2; 0+ → 2+) values of 112Sn and 114Sn have been measured to high precision. Two Coulomb excitation experiments were performed to determine the reduced transition probabilities relative to 116Sn in order to minimize the systematic errors. The obtained B(E2 ↑) values of 0:242(8) e²b² for 112Sn and 0:232(8) e²b² for 114Sn confirm the tendency of large B(E2 ↑) values for the lighter tin isotopes below the midshell 116Sn that has been observed recently in various radioactive ion beam experiments. [ABSTRACT FROM AUTHOR]

A great deal of research work has been undertaken in the α-clustering study since the pioneering discovery, half a century ago, of 12C+12C molecular resonances. Our knowledge in the physics of nuclear molecules has increased considerably and nuclear clustering remains one of the most fruitful domains of nuclear physics, facing some of the greatest challenges and opportunities in the years ahead. In this work, the occurrence of "exotic" shapes in light N = Z α-like nuclei is investigated. Various approaches of superdeformed and hyperdeformed bands associated with quasimolecular resonant structures are presented. Results on clustering aspects are also discussed for light neutron-rich oxygen isotopes. [ABSTRACT FROM AUTHOR]

We report on preliminary results from the experiment performed at Legnaro National Laboratories aiming at the investigation of the shape evolution of the 88Mo nucleus. The GDR spectra obtained for two data sets measured at 48Ti beam energy of 300 and 450 MeV corresponding to 3 and 3.8 MeV temperatures, respectively, are presented. The low energy component in GDR strength functions, similar to the theoretical predictions of LSD model, possibly indicates the presence of Jacobi shape transition. [ABSTRACT FROM AUTHOR]

We have measured the lifetime of the Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. state in 74Zn by the recoil distance Doppler-shift method at GANIL. It resulted to be of 27.6(43) ps and is consistent with previously measured values of transition rates from Coulomb excitation measurements. [ABSTRACT FROM AUTHOR]

The feasibility of measuring g -factors using the TDPAD method applied to high-energy, heavy fragmentation products is explored. The 2623keV $\ensuremath I^{\pi}=12^+$ isomer in 192Pb with $ \tau$ = 1.57 μs has been produced using the fragmentation of a 1 A GeV 238U beam. The results presented demonstrate for the first time that such heavy nuclei produced in a fragmentation reaction with a relativistic beam are sufficiently well spin-aligned. Moreover, the rather large value of the alignment, 28(10)% of the maximum possible, is preserved during the separation process allowing the determination of magnetic moments. The measured values of the lifetime, $ \tau$ = 1.54(9) μs, and the g -factor, g = - 0.175(20) , agree with the results of previous investigations using fusion-evaporation reactions. [ABSTRACT FROM AUTHOR]

RISING experiments delivered important knowledge on difficulties in performing prompt in-beam γ-ray spectroscopy measurements, caused by the use of very fast radioactive beams. The obtained results pointed out possible ways to suppress the overwhelming γ-ray background that should be considered in setting up new facilities planned at GSI and FAIR. In the course of the RISING campaign, the spectroscopy methods: γ-ray angular distribution and lifetime measurements useful in deducing B(E2) transition rates were developed. They can be effectively applied in experiments with the new generation γ-ray detector array AGATA. [ABSTRACT FROM AUTHOR]

Heavy neutron-rich nuclei have been populated through the relativistic fragmentation of a $\ensuremath ^{208}_{\ 82}{\rm Pb}$ beam at $\ensuremath E/A = 1$ GeV on a $\ensuremath 2.5 {\rm g/cm^2}$ thick Be target. The synthesised nuclei were selected and identified in-flight using the fragment separator at GSI. Approximately 300 ns after production, the selected nuclei were implanted in an $\ensuremath \sim 8$ mm thick perspex stopper, positioned at the centre of the RISING $\ensuremath \gamma$ -ray detector spectrometer array. A previously unreported isomer with a half-life $\ensuremath T_{1/2} = 163(5)$ ns has been observed in the N = 126 closed-shell nucleus $\ensuremath ^{205}_{\ 79}{\rm Au}$ . Through $ \gamma$ -ray singles and $ \gamma$ - $ \gamma$ coincidence analysis a level scheme was established. The comparison with a shell model calculation tentatively identifies the spin-parity of the excited states, including the isomer itself, which is found to be $\ensuremath I^{\pi} = (19/2^+)$ . [ABSTRACT FROM AUTHOR]

Heavy neutron-rich nuclei were populated via relativistic energy fragmentation of a E/A = 1 GeV208Pb beam. The nuclei of interest were selected and identified by a fragment separator and then implanted in a passive plastic stopper. Delayed γ rays following internal isomeric decays were detected by the RISING array. Experimental information was obtained on a number of nuclei with Z = 73-80 (Ta-Hg), providing new information both on the prolate-oblate transitional region as well as on the N = 126 closed shell nuclei. [ABSTRACT FROM AUTHOR]