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International audience; M4 resonances in light nuclei result from the p3/2 → d5/2 stretched excitations. Their configurations should be relatively simple, which makes them good benchmarks for the theoretical calculations taking into account the role of continuum couplings. The first experimental studies aiming at tracing the decay of the M4 stretched resonance in 13C, located at 21.47 MeV, were undertaken at the Cyclotron Centre Bronowice at the Institute of Nuclear Physics Polish Academy of Sciences in Kraków, Poland (IFJ PAN). They provided information on the proton and neutron decay channels of this resonance to 12B and 12C daughter nuclei, respectively. These experimental results were then compared with the theoretical calculations based on the Gamow Shell Model approach, in terms of energy, width, and in particular, the decay pattern. Furthermore, the studies of the next cases, namely, 14N and 16O, where several M4 resonances appear at around 20 MeV, have been recently performed at CCB. The new experimental findings will serve as a testing ground for future calculations describing the heavier nuclei in this important region of the nuclear chart.

The reduced transition probabilities B ( E 2 ; 0 g.s. + → 2 1 + , 2 2 + ) in Zn 70 and the full B ( E 2 ; 0 g.s. + → 2 + ) strength up to S n = 7.79 MeV in Ni 68 have been determined at the LISE/GANIL facility using the Coulomb-excitation technique at intermediate beam energy on a Pb 208 target. The γ rays emitted in-flight were detected with an array of 46 BaF 2 crystals. The angles of the deflected nuclei were determined in order to disentangle and extract the Coulomb and nuclear contributions to the excitation of the 2 + states. The measured B ( E 2 ; 0 g.s. + → 2 1 + ) of 1432(124) e 2 fm 4 for Zn 70 falls in the lower part of the published values which clustered either around 1600 or above 2000 e 2 fm 4 , while the B ( E 2 ; 0 g.s. + → 2 2 + ) of 53(7) e 2 fm 4 agrees very well with the two published values. The relatively low B ( E 2 ; 0 g.s. + → 2 1 + ) of 301(38) e 2 fm 4 for Ni 68 agrees with previous studies and confirms a local magicity at Z = 28 , N = 40 . Combining the results of the low-energy spectra of Ni 68 and Zn 70 and their shell-model interpretations, it is interesting to notice that four different shapes (spherical, oblate, prolate, and triaxial) are present. Finally, a summed E 2 strength of only about 150 e 2 fm 4 has been found experimentally at high excitation energy, likely due to proton excitations across the Z = 28 gap. The experimental distribution of this high-energy E 2 excitation agrees with shell-model calculations, but its strength is about two times weaker.

International audience; “Stretched” states are examples of the simplest nuclear excitations in the continuum, thus offering an excellent testing ground for various theoretical approaches. The decay of the stretched single-particle state in 13C, located at 21.47 MeV, was investigated in an experiment performed recently at the Cyclotron Centre Bronowice (CCB) at IFJ PAN in Kraków. First experimental information on the proton and neutron decay channels of this resonance was obtained by employing coincidence measurement of protons inelastically scattered on the 13C target and γ rays from daughter nuclei. The new experimental findings will be used for testing predictions obtained by the Gamow Shell Model calculations.

The low-lying dipole strength in the 90,94Zr nuclei was investigated via (p,p′γ) at 80 MeV and (α,α′γ) at 130 MeV. The experiments, made at RCNP, used the magnetic spectrometer Grand Raiden for the scattered particles and the array CAGRA with HPGe detectors for the γ-decay. For 94Zr these are the first data for both reactions and for 90Zr these are the first data with (p,p′γ) and the first ones at high resolution for (α,α′γ). The comparison of the present results for the two nuclei with existing (γ,γ′) data shows that both nuclear probes produce an excitation pattern different than that of the electromagnetic probes. DWBA calculations were made using form factors deduced from transition densities, based on RPA calculations, characterized by a strong neutron component at the nuclear surface. A combined analysis of the two reactions was performed for the first time to investigate the isoscalar character of the 1− states in 90,94Zr. The (p,p′γ) cross section was calculated using values for the isoscalar electric dipole energy-weighted sum rule (E1 ISEWSR) obtained from the (α,α′γ) data. The isoscalar strength for 90Zr was found to exhaust 20 ± 2.5% of the EWSR in the energy range up to 12 MeV. In case of 94Zr, a strength of 9 ± 1.1% of the EWSR was found in the range up to 8.5 MeV. Although an overall general description was obtained in the studied energy intervals, not all proton cross sections were well reproduced using the isoscalar strength from (α,α′γ). This might suggest mixing of isoscalar and isovector components and that this mixing and the degree of collectivity are not the same for all the 1− states below the particle binding energy.

The low-spin structure of the semimagic ^{64}Ni nucleus has been considerably expanded: combining four experiments, several 0^{+} and 2^{+} excited states were identified below 4.5 MeV, and their properties established. The Monte Carlo shell model accounts for the results and unveils an unexpectedly complex landscape of coexisting shapes: a prolate 0^{+} excitation is located at a surprisingly high energy (3463 keV), with a collective 2^{+} state 286 keV above it, the first such observation in Ni isotopes. The evolution in excitation energy of the prolate minimum across the neutron N=40 subshell gap highlights the impact of the monopole interaction and its variation in strength with N.

Performance of the ELIGANT-GN array being developed at ELI-NP was evaluated using dedicated GEANT4 simulation code. The array is designed to consist of 17 LaBr3:Ce and 17 CeBr3 detectors as well as 33 BC501A and 29 6Li-glass detectors. The energy and time responses of the detectors were studied giving information on gamma and neutron absolute detection efficiencies of the array. A planned day-one experiment regarding the gamma and neutron decay from GDR in 208Pb is discussed and, based on simulations, the data analysis procedure is proposed. The detection efficiencies as well as the count rates estimations are presented.

Photoneutron measurements in the Giant Dipole Resonance region have been recently performed using quasimonochromatic Laser Compton Scattering γ -ray beams at NewSUBARU (Japan) for 59Co, 89Y, 103Rh, 139La, 159Tb, 165Ho, 169Tm, 181Ta, 197Au and 209Bi. Experimental ( γ , x n ) with x = 1 – 4 photoneutron cross sections have been obtained with a direct neutron-multiplicity sorting method associated to a flat-efficiency neutron detector , which operates under single firing conditions obtained by low reaction rates. In this paper, we discuss recent developments to the neutron-multiplicity sorting procedure dedicated to (i) resolving multiple firing events and to (ii) extracting the average energies of ( γ , x n ) photoneutrons. The method is tested on 159Tb experimental data.

The Coordinated Research Project (CRP) with the code F41032 has been launched by the International Atomic Energy Agency (IAEA) in 2016 as a 5-year project with the scientific goal being two-fold: 1) updating the 2000 photonuclear data library and 2) constructing a reference database of photon strength functions. We report the experimental technique and methodology used for the former goal and selected giant-dipole resonance (GDR) data updated in the IAEA-CRP.

International audience; For a few years, the medical cyclotron Proteus C-235 at the Cyclotron Centre Bronowice in Kraków, Poland has been regularly used for nuclear structure experiments. One of the ongoing studies is focused on the γ decay of collective states populated in (p, p0γ) reactions. In a recent experiment, γ decays of excited states in the energy region of the Pygmy Dipole States in 208Pb have been observed. Good efficiency and energy resolution provided by the PARIS clusters and LaBr3:Ce scintillators facilitate a comparison of the obtained energy spectra with previous measurements of pygmy states in this nucleus.

International audience; 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 γ rays 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 γ decays of excited states to selected low-lying levels in 208Pb were obtained, allowing a look into the Brink–Axel hypothesis.

A Coulomb-excitation experiment to study electromagnetic properties of Ca42 was performed using a 170-MeV calcium beam from the TANDEM XPU facility at INFN Laboratori Nazionali di Legnaro. γ rays from excited states in Ca42 were measured with the AGATA spectrometer. The magnitudes and relative signs of ten E2 matrix elements coupling six low-lying states in Ca42, including the diagonal E2 matrix elements of 21+ and 22+ states, were determined using the least-squares code gosia. The obtained set of reduced E2 matrix elements was analyzed using the quadrupole sum rule method and yielded overall quadrupole deformation for 01,2+ and 21,2+ states, as well as triaxiality for 01,2+ states, establishing the coexistence of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in Ca42. The experimental results were compared with the state-of-the-art large-scale shell-model and beyond-mean-field calculations, which reproduce well the general picture of shape coexistence in Ca42.

International audience; We performed experiments to study the low-energy part of the E1 response (Pygmy Dipole Resonance) in $^{90,94}$Zr nuclei, by measuring the (p,p’γ) and (α,α’γ) inelastic scattering reactions at energies Ebeam,p = 80 MeV and Ebeam,α = 130 MeV respectively. The inelastically scattered particles were measured by employing the high-resolution spectrometer Grand Raiden. The gamma-rays emitted following the de-excitation of the Zr target nuclei were detected using both the clover type HPGe detectors of the CAGRA array and the large volume LaBr3:Ce scintillation detectors from the HECTOR+ array. Some preliminary results are presented here.

A search for shape isomers in the ^{66}Ni nucleus was performed, following old suggestions of various mean-field models and recent ones, based on state-of-the-art Monte Carlo shell model (MCSM), all considering ^{66}Ni as the lightest nuclear system with shape isomerism. By employing the two-neutron transfer reaction induced by an ^{18}O beam on a ^{64}Ni target, at the sub-Coulomb barrier energy of 39 MeV, all three lowest-excited 0^{+} states in ^{66}Ni were populated and their γ decay was observed by γ-coincidence technique. The 0^{+} states lifetimes were assessed with the plunger method, yielding for the 0_{2}^{+}, 0_{3}^{+}, and 0_{4}^{+} decay to the 2_{1}^{+} state the B(E2) values of 4.3, 0.1, and 0.2 Weisskopf units (W.u.), respectively. MCSM calculations correctly predict the existence of all three excited 0^{+} states, pointing to the oblate, spherical, and prolate nature of the consecutive excitations. In addition, they account for the hindrance of the E2 decay from the prolate 0_{4}^{+} to the spherical 2_{1}^{+} state, although overestimating its value. This result makes ^{66}Ni a unique nuclear system, apart from ^{236,238}U, in which a retarded γ transition from a 0^{+} deformed state to a spherical configuration is observed, resembling a shape-isomerlike behavior.

Iodine-131 (I-131) is often used in thyroid diagnostics and therapy. External and internal exposure to radioiodine can lead to molecular and cellular damage in peripheral blood lymphocytes. The aim of this study was to explore the influence of low and high doses of I-131 on susceptibility to ionizing radiation. Study groups consisted of 30 individuals free of thyroid diseases, 41 patients exposed diagnostically to low doses of I-131, and 37 hyperthyroidism patients exposed therapeutically to high doses. The standardized DNA repair competence assay was used to test the efficacy of the fast DNA repair process in G0 cells. Cytogenetic preparations were made in fresh blood samples before and after challenging cells in vitro with X-ray dose. The frequency of sister chromatid exchanges (SCE) and percentage of cells with significantly elevated numbers of SCE were used as cytogenetic biomarkers associated to homologous recombination and compared to reported earlier cytogenetic biomarkers of cancer risk. Strong individual variation in the biomarkers is observed in all investigated groups before and after challenging. Nevertheless, the efficiency of post challenging fast repair is significantly high in the patients exposed to diagnostic I-131 doses than in unexposed control group and linked to decreased cytogenetic damage. However, 5 weeks after administration of therapeutic doses, significant increases of unrepaired post challenging DNA and cytogenetic damages were observed indicating a health risk. Results also suggest that the appearance of cancers in immediate families might influence DNA repair differently in patients exposed to low than to high doses.

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. ispartof: Acta Physica Polonica B vol:48 issue:3 pages:635-639 ispartof: location:Zakopane: POLAND status: published

K. Hadyńska-Kl¸ek et al. ; 7 pags., 3 figs., 2 tabs., Shape parameters of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in Ca42 were determined from E2 matrix elements measured in the first low-energy Coulomb excitation experiment performed with AGATA. The picture of two coexisting structures is well reproduced by new state-of-the-art large-scale shell model and beyond-mean-field calculations. Experimental evidence for superdeformation of the band built on 02+ has been obtained and the role of triaxiality in the A∼40 mass region is discussed. Furthermore, the potential of Coulomb excitation as a tool to study superdeformation has been demonstrated for the first time. © 2016 American Physical Society, Special gratitude goes to the INFN LNL and HIL Warsaw technical staff for their support and help, in particular, the accelerator crews for providing intense and good-quality 42Ca and 32S beams. K. H.-K. acknowledges support from the Research Council of Norway under the project Grant No. 213442. T. R. R. acknowledges computing time at GSI-Darmstadt and support from Spanish MINECO under Programa Ramon y Cajal 11420 and FIS-2014-53434-P, H. N. acknowledges support from Helmholtz Association through the Nuclear Astrophysics Virtual Institute NAVI (No. VH-VI-417). We also acknowledge the support by Generalitat Valenciana, Spain, under the grant PROMETEOII/2014/019 and by the FEDER funds of the European Commission (A. Gadea), Spanish Ministerio de Economía y Competitividad under Contract No. FPA2014-57196-C5 (A. J., A. Gadea), German Bundesministerium für Bildung und Forschung (BMBF) under Contract No. 05P12PKFNE TP4 (B. Birkenbach), the Polish National Science Centre under Projects No. DEC-2013/10/M/ST2/00427, No. DPN/N190/ AGATA/2009, No. 2011/03/B/ST2/01894, No. UMO- 2014/14/M/ST2/00738 (COPIN-INFN Collaboration), and No. 2015/17/B/ST2/01534.

The γ decay from the high-lying states of ^140Ce excited via inelastic scattering of ^17O at a bombarding energy of 340 MeV was measured using the high-resolution AGATA-demonstrator array in coincidence with scattered ions detected in two segmented Δ E-E silicon detectors. Angular distributions of scattered ions and emitted γ rays were measured, as well as their differential cross sections. The excitation of 1^− states below the neutron separation energy is similar to the one obtained in reactions with the α isoscalar probe. The comparison between the experimental differential cross sections and the corresponding predictions using the distorted-wave Born approximation allowed us to extract the isoscalar component of identified 1^− pygmy states. For this analysis the form factor obtained by folding microscopically calculated transition densities and optical potentials was used.

A study of fusion-evaporation and (partly) fusion-fission channels for the $^{88}$Mo compound nucleus, produced at different excitation energies in the reaction $^{48}$Ti + $^{40}$Ca at 300, 450 and 600 MeV beam energies, is presented. Fusion-evaporation and fusion-fission cross sections have been extracted and compared with the existing systematics. Experimental data concerning light charged particles have been compared with the prediction of the statistical model in its implementation in the Gemini++ code, well suited even for high spin systems, in order to tune the main model parameters in a mass region not abundantly covered by exclusive experimental data. Multiplicities for light charged particles emitted in fusion evaporation events are also presented. Some discrepancies with respect to the prediction of the statistical model have been found for forward emitted $\alpha$-particles; they may be due both to pre-equilibrium emission and to reaction channels (such as Deep Inelastic Collisions, QuasiFission/QuasiFusion) different from the compound nucleus formation.

A multitude of discrete ${2}^{+}$ states in $^{124}\text{Sn}$ with energy up to 5 MeV were populated and identified with the $(^{17}\text{O}$, $^{17}\mathrm{O}^{\ensuremath{'}}\ensuremath{\gamma})$ reaction at 340 MeV. Cross sections were compared with distorted wave Born approximation predictions and in general a good agreement was found. The measured energy and intensity distributions of the ${2}^{+}$ states are very similar to the predictions based on self-consistent density functional theory and extended QRPA approach accounting for multiphonon degrees of freedom. This provides evidence of the excitation of the pygmy quadrupole resonance in skin nuclei.

High-energy giant dipole resonance (GDR) γ rays were measured following the decay of the hot, rotating compound nucleus of 88Mo, produced at excitation energies of 124 and 261 MeV. The reaction 48Ti+ 40Ca at 300 and 600 MeV bombarding energies has been used. The data were analyzed using the statistical modelMonte Carlo code GEMINI++. It allowed extracting the giant dipole resonance parameters by fitting the high-energy γ -ray spectra. The extracted GDR widths were compared with the available data at lower excitation energy and with theoretical predictions based on (i) The Lublin-Strasbourg drop macroscopic model, supplemented with thermal shape fluctuations analysis, and (ii) The phonon damping model. The theoretical predictions were convolutedwith the population matrices of evaporated nuclei from the statistical model GEMINI++. Also a comparison with the results of a phenomenological expression based on the existing systematics, mainly for lower temperature data, is presented and discussed. A possible onset of a saturation of the GDR width was observed around T = 3 MeV.

We discuss the role of photoneutron reaction data in nuclear physics and astrophysics in conjunction with the Coordinated Research Project of the International Atomic Energy Agency with the code F41032 (IAEA-CRP F41032)., SCOPUS: cp.p, info:eu-repo/semantics/published

2(+) and 1(-) states in Zr-90 were populated via the (O-17, O-17 'gamma) reaction at 340 MeV. The gamma decay was measured with high resolution using the AGATA (advanced gamma tracking array demonstrator array). Differential cross sections were obtained at few different angles for the scattered particle. The results of the elastic scattering and inelastic excitation of 2(+), 3(,)(-) and 1(-) states are compared with distorted-wave Born approximation (DWBA) calculations, using both the standard collective form factor and a form factor obtained by folding microscopically calculated transition densities. This allowed to extract the isoscalar component of the 1(-) state at 6.424 MeV. The comparison of the present (17O, 17O 'gamma) data with existing (gamma,gamma') and (p, p') data in the corresponding region of the gamma continuum (6-11 MeV), characterized by a large E1 component, shows completely different behaviors of the cross section as a function of the nuclear excitation energy. The comparison of the data with DWBA calculations suggests a decrease of the isoscalar strength in the cross section with increasing excitation energy.

The properties of pygmy dipole states in Pb-208 were investigated using the Pb-208(O-17, O-17'gamma) reaction at 340 MeV and measuring the gamma decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted gamma rays and of the scattered particles were measured. The results are compared with (gamma, gamma') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2(+) and 3(-) states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first time. This has allowed us to extract the isoscalar component of the 1(-) excited states from 4 to 8 MeV.

The properties of pygmy dipole states in 208Pb were investigated using the 208Pb(17O, 17O'γ) reaction at 340 MeV and measuring the γ decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted γ rays and of the scattered particles were measured. The results are compared with (γ, γ') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2+ and 3- states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first time. This has allowed us to extract the isoscalar component of the 1- excited states from 4 to 8 MeV.

A measurement of the high-lying states in 208Pb has been made using 17O beams at 20 MeV/u. The gamma decay following inelastic excitation was measured with the detector system AGATA Demonstrator based on segmented HPGe detectors, coupled to an array of large volume LaBr3:Ce scintillators and to an array of Si detectors. Preliminary results in comparison with (γ,γ’) data, for states in the 5-8 MeV energy interval, are presented.

We investigated the response of a 3″ × 3″ (7.62 cm × 7.62 cm) LaBr 3 :Ce detector to monochromatic protons within an energy range of 70–230 MeV. The experiment was performed at the new cyclotron at the Cyclotron Centre Bronowice (CCB) of the Henryk Niewodniczanski Institute of Nuclear Physics, Krakow, Poland. Protons with energies between 70 and 185 MeV were stopped inside the crystal. Three different values of PMT high voltage were used, in each case, the energy resolution, the quenching factor with respect to the gamma rays were measured. In addition, the anode pulses were acquired for both gamma rays (from a CmC source) and protons and the comparison between them will be shown.

Lifetimes of high-spin states in 69As have been measured using Doppler shift attenuation technique with the GASP and RFD setup. The determined transition probabilities indicate large deformation associated with some rotational bands in this nucleus.

An individual’s genetic constitution and lifestyle, e.g., diet and levels of physical activity, can affect the body’s response to various exogenous agents including therapeutic treatment. There is a strong need to combine studies on variability in a cellular response to genotoxic exposure with predisposition of the patient to diseases development and healing. In this study a variation in responses to challenging dose of X rays in lymphocytes from healthy donors and prostate cancer patients were compared on the molecular and mitotic levels. Blood was collected from healthy donors BPH (Benign Prostate Hyperplasia), and prostate cancer patients. Among cancer patients 33% never smoke 46.7% were former smokers. Immediately after collecting the blood a challenging irradiation was performed followed by culturing procedures for classic cytogenetics and FISH techniques with a probe for the whole chromosome 1. In DNA damage investigations, isolated and cryopreserved lymphocytes were thawed and their viability examined before molecular studies. To evaluate individual susceptibility, defrosted lymphocytes were exposed to 4 Gy dose of X-rays and the extent of DNA damage was studied right after irradiation with the alkaline version of the single cell gel electrophoresis (SCGE) assay. To asses variability in the DNA repair competency the residual (unrepaired) DNA damage was detected again after one hour of incubation, during which irradiated cells had the condition allowing to complete the fast DNA repair process. Visible difference between DNA susceptibilities to the challenging dose was observed between investigated groups. However, variation between individuals in repair efficiency of the DNA damage induced by the challenging treatment was significantly higher in lymphocytes of prostate cancer patients than that of BPH and healthy donors (p

The main aim of this study was a deeper understanding of the nuclear structure properties of the soft dipole modes in 140 Ce, excited via inelastic scattering of weakly bound 17 O projectiles. An important aim was to investigate the ‘splitting’ of the PDR into two parts: a low-energy isoscalar component dominated by neutron-skin oscillations and a higher-energy component lying on the tail of the giant dipole resonance of a rather isovector character. This was already observed for this nucleus, investigated in (α, α′) and (γ, γ′) experiments. The experiment was performed at Laboratori Nazionali di Legnaro, Italy. Inelastic scattering of 17 O ion beam at − 2 0M eV A 1 was

Sr isotopes. The coexistence of the prolateandoblateshapesisatypicalphenomenoninthenucleiwithmassAˇ70.Here, the number of active nucleons is large enough to create a coherentmotion but, on the other hand, this collectivity can still be tracked to thesingleparticledegreesoffreedom. Excitedstateslifetimemeasurementspro-videinformationonthenucleardeformationandthepropertiesofcollectivestructures,varietyofwhichoccursinthisregionofthenuclearchart. Themeasurements,however,arequitedifficulttoperformandrelevantdataonelectromagneticpropertiesofsuchbandsathighspinarestillunavailable.2. Experimental setupIn the present experiment

We report on tests of LaBr3:Ce-NaI:Tl phoswich detectors with-rays at various γ-ray energies, up to 22.56 MeV, using radioactive sources and nuclear reactions induced by proton beams delivered by accelerators at IFJ PAN Krakow and PLF Mumbai. Two-dimensional analysis of complex waveforms recorded with digital electronics is compared to analog discrimination methods. Both approaches allow to resolve the LaBr3:Ce and NaI:Tl signal components, and to construct clean associated γ-ray spectra. A digital algorithm to be implemented for the PARIS scintillator array is investigated.

The Coulomb excitation experiment to study electromagnetic structure of low-lying states in Ca-42 with a focus on a possible superdeformation in this nucleus was performed at the Laboratori Naziona ...