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Multi-Nucleon Transfer (MNT) reactions have been used for decades as a reaction mechanism, in order to populate excited states in nuclei far from stability and to perform nuclear structure studies. Nevertheless, the development of set-ups involving high acceptance tracking magnetic spectrometers (mainly existing in Europe), coupled with the Advanced GAmma Tracking Array (AGATA) opens new possibilities, especially if they are used in conjunction with high-intensity stable beams or ISOL RIBs. In this article, we will discuss the capabilities of such set-ups aiming at different goals, including complete information in high-resolution spectroscopy as well as lifetime measurements.

9 pags., 8 figs., 4 tabs., Background: The Xe isotopic chain with four valence protons above the Z=50 shell closure is an ideal laboratory for the study of the evolution of nuclear deformation. At the N=82 shell closure, Xe136 presents all characteristics of a doubly closed shell nucleus with a spherical shape. In the very neutron-deficient isotopes close to N=50, the α-decay chain of Xe was investigated to probe the radioactive decay properties near the drip-line and the magicity of Sn100. Additionally, the Xe isotopes present higher order symmetries in the nuclear deformation such as the octupole degree of freedom near N=60 and N=90 or O(6) symmetry in stable isotopes. Purpose: The relevance of the O(6) symmetry has been investigated by measuring the spectroscopic quadrupole moment of the first excited states in Xe124. In the O(6) symmetry limit, the spectroscopic quadrupole moment of collective states is expected to be null. Method: A stable Xe124 beam with energies of 4.03A MeV and 4.11A MeV was used to bombard a natW target at the GANIL facility. Excited states were populated via the safe Coulomb excitation reaction. The collision of the heavy ions with a large Z at low energy make this reaction sensitive to the diagonal E2 matrix element of the excited states. The recoils were detected in the VAMOS++ magnetic spectrometer and the γ rays in the AGATA tracking array. The least squares fitting code gosia was used for the analysis to extract both E2 and M1 transitional and E2 diagonal matrix elements. Results: The rotational ground state band was populated up to the 81+ state as well as the 22+ and 42+ states. Using high precision spectroscopic data to constrain the gosia fit, the spectroscopic quadrupole moments of the 21+, 41+, and 61+ states were determined for the first time. Conclusions: The spectroscopic quadrupole moments were found to be negative, large, and constant in the ground state band underlining the prolate axially deformed ground state band of Xe124. The present experimental data confirm that the O(6) symmetry is substantially broken in Xe124., This work was supported by STFC(UK). This research was also supported by the OASIS Project No. ANR-17-CE31-0026, by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under contract number DE-AC02-06CH11357, by the European Regional Development Fund with Contract No. GINOP-2.3.3-15-2016-00034 and by the Spanish Ministerio de Ciencia e Innovacion under contract PID2020-118265GB-C41. Work partially supported by Grants FPA2017-84756-C4, PID2020- 118265GB-C4 by MCIN/ AEI /10.13039/501100011033, PROMETEO/2019/005 by Generalitat Valenciana and by the FEDER EU funds.

7 pags., 3 figs., 1 tab., The reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood. The conclusion is that seniority is largely conserved in the first πg_{9/2} orbital., This work was partially supported by MCIN/AEI/10.13039/501100011033 and Generalitat Valenciana, Spain, under Grants No. FPA2017-84756-C4, No. PID2020–118265GB-C4, and No. PROMETEO 2019/005, by the EU FEDER funds, by the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. n654002, by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357, by STFC(UK) and by the Croatian Science Foundation under Projects No. 7194 and No. IP-2018-01-1257.

International audience; A β-decay experiment aiming at investigation of the low-spin structure of 100Zr was performed using the GRIFFIN spectrometer at TRIUMFISAC. Based on the obtained data, a new 2 + state is postulated which is degenerate in energy with the established (5+) level at 2209 keV.

At the beginning of the 2020 pandemic, I grew concerned and also curious about how theatre educators would transition theatre and drama instruction to an online platform. I began a research study i...

International audience; Target properties such as thickness and composition are essential ingredients in nuclear physics experiments, therefore, dedicated analyses to evaluate them before and/or after the measurement are often performed. In some experimental techniques, the exploited detectors allow for the evaluation of these properties on-line, i.e. directly during the experiment. In this paper, we report on the use of analysis methods coming from the Rutherford backscattering spectroscopy technique to obtain on-line information on the target used in a nuclear physics experiment. This measurement was performed at INFN LNL by exploiting the low-energy Coulomb excitation technique. The results have been compared with an independent Rutherford backscattering spectroscopy analysis of the same target performed at INFN LABEC in Florence.

A elevação da comercialização e produção de alimentos é acompanhada pelo aumento de infecções, enfermidades e mortes relacionadas ao consumo de alimentos contaminados, fazendo com que os processos de produção sejam cada vez mais controlados, a fim de se assegurar a inocuidade. O objetivo principal desse trabalho é identificar e caracterizar as inovações tecnológicas que ajudam as indústrias alimentares no controle de segurança dos alimentos. Outro objetivo é apresentar os avanços e melhoramentos realizados na indústria de alimento. A metodologia utilizada na pesquisa foi a revisão bibliográfica na temática das tecnologias utilizadas pela indústria alimentar, culminando em um trabalho que tem, ao mesmo tempo, características qualitativas e explicativas. Uma tecnologia apresentada neste estudo é a imagem química, a qual permite identificar o mapa de composição química dos alimentos, níveis de agrotóxicos e até mesmo matérias estranhas, sendo mais efetiva do que as técnicas de inspeção comumente utilizadas. Além disso, a tecnologia de embalagens inteligentes é outro avanço estudado, a qual tem um papel importante na preservação de alimentos.

Background: The heaviest T-z = 0 doubly-magic nucleus, Sn-100, and the neighboring nuclei offer unique opportunities to investigate the properties of nuclear interaction. For instance, the structur ...

The GALILEO γ -ray spectrometer has been constructed at the Legnaro National Laboratory of INFN (LNL-INFN). It can be coupled to advanced ancillary devices which allows nuclear structure studies employing the variety of in-beam γ -ray spectroscopy methods. Such studies benefit from reactions induced by the intense stable beams delivered by the Tandem-ALPI-PIAVE accelerator complex and by the radioactive beams which will be provided by the SPES facility. In this paper we outline two experiments performed within the experimental campaign at GALILEO coupled to the EUCLIDES Si-ball and the Neutron Wall array. The first one was aimed at spectroscopic studies in A=31 mirror nuclei and the second one at measurements of lifetimes of excited states in nuclei in the vicinity of 100 Sn.

The GALILEO array is a high-efficiency γ -ray spectrometer, resident at the Legnaro National Laboratory (LNL)in Italy, and it is currently used in combination with the Si-ball EUCLIDES for the detection of charged-particles. The combined setup was used in the 6 Li+89Y experiment with incident energies of 22 MeV and 34 MeV to investigate the influence of breakup and transfer of weakly bound projectile on the fusion process. Using the coincidence by the charged particles and γ -rays, the different reaction channels can be clearly identified and the different reaction mechanisms can be clearly studied. It is shown that this facility can be used well to explore the fusion reaction mechanisms induced by weakly bound nuclei.

ispartof: PHYSICAL REVIEW C vol:103 issue:4 status: published

The electromagnetic structure of Zn66 at low excitation energy was investigated via low-energy Coulomb excitation at INFN Legnaro National Laboratories, using the Gamma Array of Legnaro Infn Laboratories for nuclEar spectrOscopy (GALILEO) γ-ray spectrometer coupled to the SPIDER (Silicon PIe DEtectoR). A set of reduced E2, E3, and M1 matrix elements was extracted from the collected data using the gosia code, yielding 12 reduced transition probabilities between the low-spin states and the spectroscopic quadrupole moment of the 21+ state. The B(E2) values for transitions depopulating the 02+ state have been determined for the first time, allowing for the lifetime of this state to be deduced and, consequently, the ρ2(E0;02+→01+) monopole transition strength to be extracted. In addition, the B(E3;31−→01+) value has been determined for the first time in a Coulomb excitation experiment. The obtained results resolve the existing discrepancies between literature lifetimes and demonstrate that Zn66 cannot be described by using simple collective models. Therefore, new state-of-the-art beyond-mean-field and large-scale shell-model calculations were performed in order to interpret the structure of this nucleus. Both the experimental and theoretical results suggest that the triaxial degree of freedom has an important impact on electromagnetic properties of Zn66, while the unique features of the 02+ state indicate its distinct and rather isolated structure.

GALILEO, a new 4 π high-resolution γ -detection array, based on HPGe detectors, has been developed and installed at the Legnaro National Laboratories. The GALILEO array greatly benefits from a fully-digital read-out chain, customized DAQ, and a variety of complementary detectors to improve the resolving power by the detection of particles, ions or high-energy γ -ray transitions. In this work, a full description of the array, including electronics and DAQ, is presented together with its complementary instrumentation.

Gamma-ray angular distributions in oriented $$^{92}$$ Mo produced via the $$^{6}$$ Li+ $$^{89}$$ Y reaction were studied in this work. The characteristic $$\gamma $$ rays in $$^{92}$$ Mo were measured by means of the GALILEO array, which is composed of 25 Compton-suppressed HPGe detectors arranged in a nearly 2 $$\pi $$ geometry. A detailed analysis of the spin-alignment attenuation factors ( $$\alpha _2$$ ) for different excited states in $$^{92}$$ Mo was performed, by analyzing the measured angular distribution coefficients of several pure-E2 transitions. The relationship between $$\alpha _2$$ and the spin was established in $$^{92}$$ Mo and the 244-keV transition between the 5 $$^-_1$$ and 4 $$^+_1$$ states resulted to have a E1 + M2 character with a mixing ratio ( $$\delta $$ ) of $$-0.05^{+0.05}_{-0.06}$$ , consistent with shell model calculations.

The unprecedented capabilities of state-of-the-art segmented germanium-detector arrays, such as AGATA and GRETA, derive from the possibility of performing pulse-shape analysis. The comparison of the net- and transient-charge signals with databases via grid-search methods allows the identification of the $\gamma$-ray interaction points within the segment volume. Their precise determination is crucial for the subsequent reconstruction of the $\gamma$-ray paths within the array via tracking algorithms, and hence the performance of the spectrometer. In this paper the position uncertainty of the deduced interaction point is investigated using the bootstrapping technique applied to $^{60}$Co radioactive-source data. General features of the extracted position uncertainty are discussed as well as its dependence on various quantities, e.g. the deposited energy, the number of firing segments and the segment geometry., Comment: 9 pages, 8 figures

PM10 samples were collected in a site of Apulia region (South-East Italy) near a steel plant when the winds were blowing from the NW and the SE to exclude and include, respectively, the contribution of the industrial source in order to study the aerosol particles in detail and attribute them to the most appropriate emission sources. Size, morphology and chemical composition of 6500 individual particles, with an equivalent spherical diameter (ESD) between 0.4 ˗ 1 μm, 1 ˗ 2.5 μm and 2.5 ˗ 10 μm, were analysed by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM - EDX). These particles were classified in the thirteen groups: aluminosilicates, silicates, iron oxides, metal oxides, iron mixtures, aluminosilicates with sulphur, calcium sulphates, silicate-sulphate mixed particles, carbonates, carbonates-silicates, soot, biological particles and carbon rich particles. Source apportionment analyses were carried out separately for the three dimensional ranges considered and for the two wind directions from North-West and South-East and nine main sources were distinguished. The soil and the soot components are higher when the wind blow from the NW than the SE, while the anthropogenic sources are evident with the wind from the SE due to the presence of iron and carbonaceous particles characterized by typical spherical shapes and chemical elements as Ca, Na and K which could to be indicative of industrial activity. The single particle analysis let better identify the emission sources that persist on the territory, attributing to them the particles characterized by peculiar morphology and chemical composition.

The aim of this study is to characterize the air quality in a Mediterranean port city. The impact of ship emissions on both gaseous and particulate pollutants has been investigated through an integrated methodology which includes atmospheric flow and dispersion numerical modelling as well as chemical composition and statistical analyses. Specifically, chemical compositional data (ionic fraction, carbonaceous compounds, and metals) of PM2.5 were acquired during an experimental field campaign carried out in the port city of Brindisi (Apulia Region, Southern Italy). The sampling site was located on the roof of a building (ASI) within the port area. Given the complexity of the site in which both domestic buildings and a large industrial area are present, analyses were done by selecting different wind sectors to test different techniques to discriminate between sources. Linear Discriminant Analysis (LDA) and Principal Component Analysis (PCA) were applied to evaluate statistical differences in the composition of PM2.5 sampled within the area when the sampling site was downwind to the port or to the urban-industrial area. Only LDA allowed to discriminate the separation between urban-industrial and port macroareas. Those results were further confirmed in terms of PM2.5 concentrations directly associated to ship emissions using a coupled modelling approach. The mesoscale model BOLCHEM was used to investigate the contribution of ship emissions both on primary and secondary PM2.5 concentration in the area surrounding the port, as well as on PM10, NOX and O3 concentrations. Then, the model was coupled offline with the local dispersion model ADMS-Urban. The adopted approach was crucial to evaluate the spatial distribution of the impact of ship emissions. BOLCHEM results showed that in the cell of the port the average impact of ship emissions on NOX was 37.6%, and −11.7% on O3. The average impact on PM2.5 was 6.1%, distributed between primary (2.7%) and secondary fraction (3.4%). At local scale, the analysis of high-resolution modelling results obtained from ADMS-Urban highlighted that, at ASI position, the impact of ship emissions on PM2.5 was 6.8% when the sampling site was positioned downwind to the port area and reduced to lower than 3.0% at about 2 km from the sources.

The lifetime of the 2(+) and 9(-), 11(-), 13(-), 15(-) states in the neutron-deficient Te-110 was measured for the first time using the recoil distance Doppler shift technique. The reported value of the reduced transition probability B(E2; 0(g.s)(+) -> 2(+)) = 4.3(8) x 10(3) e(2) f m(4) supports the systematic for even-mass Te isotopes and was interpreted g.s in the framework of the large-scale shell model and cranked shell model calculations. The measured reduced transition probabilities in the negative-parity yrast band revealed the upward trend towards the high spins. The enhanced collectivity is discussed in terms of the tilted axis cranking approach and the symmetry configuration mixing method with the Gogny D1S interaction., DoE [DE-FG02-95ER4093]; Spanish MICINN [PGC2018-094583-B-I00], The authors would like to thank the technical staff of the LNL Legnaro facility for their assistance in providing excellent operation of the XTU-tandem accelerator. The authors wish to acknowledge the support of local engineers P. Cocconi and R. Isocrate. The work was partially supported by the DoE Grant No. DE-FG02-95ER4093 and Spanish MICINN Grant No. PGC2018-094583-B-I00.

COVID-19, the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, showed higher severity and lethality in male older adults . There are currently no specific treatments. Studies are evaluating the efficacy of monoclonal antibodies against interleukin-6 receptor. Here we present the case of a 98-years old man admitted to our COVID-Hospital with acute respiratory failure. Comprehensive geriatric assessment showed no signs of frailty. First-line therapy with hydroxychloroquine and anticoagulants was not effective. Patient was administered intravenous monoclonal antibodies, and he showed remarkable clinical improvement. This case suggests that age alone should not preclude access to new therapeutic approaches. Comprehensive, multisciplinary, multidomain approaches are needed to develop patient-tailored treatments against COVID-19.

Fine structure in the α decay of Th90221, populating excited states in Ra88217, was studied using αγ-coincidence spectroscopy. Two α-decay branches from Th221 have been newly observed, with Eα(keV)[bα(%)]=7951(8)[0.14(3)] and 8247(3)[1.51(12)], together with three previously known branches. Also, two new states in Ra217 were identified at E = 177 and 227 keV. The ground-state configurations of the odd-A, N = 131 transitional isotones above Pb208 are interpreted from their α-decay fine structure systematics and considered in terms of predictions using spherical shell and reflection-asymmetric models.

Physical review / C 102(5), 054304 (2020). doi:10.1103/PhysRevC.102.054304, Published by Inst., Woodbury, NY

Lifetimes of negative-parity states have been determined in the neutron deficient semi-magic (N = 50) nucleus $$^{95}\mathrm {Rh}$$ 95 Rh . The fusion-evaporation reaction $$^{58}Ni(^{40}Ca, 3p)$$ 58 N i ( 40 C a , 3 p ) was used to populate high-spin states in $$^{95}\mathrm {Rh}$$ 95 Rh at the Grand Accélérateur National d’Ions Lourds (GANIL) accelerator facility. The results were obtained using the Doppler Shift Attenuation Method (DSAM) based on the Doppler broadened line shapes produced during the slowing down process of the residual nuclei in a thick $$6\;\mathrm {mg/cm}^2$$ 6 mg / cm 2 metallic target. B(M1) and B(E2) reduced transition strengths are compared with predictions from large-scale shell-model calculations.

Three nearly degenerate pairs of doublet bands are identified in $^{131}$Ba. Two of them, with positive-parity, are interpreted as pseudospin-chiral quartet bands. This is the first time that a complete set of chiral doublet bands built on the pseudospin partners π(d5/2,g7/2) is observed. The chiral bands with opposite parity built on 3-quasiparticle configurations are directly connected by many E1 transitions, without involving an intermediary non-chiral configuration. The observed band structures in $^{131}$Ba have been investigated by using the reflection-asymmetric particle rotor model. The energies and the electromagnetic transition ratios of the three pairs of doublet bands observed in $^{131}$Ba are reproduced and they are interpreted as chiral doublet bands with three-quasiparticle configurations. It is the first time that multiple chiral bands are observed in the presence of enhanced octupole correlations and pseudospin symmetry.

Background: The phenomenon of fusion hindrance may have important consequences on the nuclear processes occurring in astrophysical scenarios, if it is a general behavior of heavy-ion fusion at extreme subbarrier energies, including reactions involving lighter systems, e.g., reactions in the carbon and oxygen burning stages of heavy stars. The hindrance is generally identified by the observation of a maximum of the $S$ factor vs energy. Whether there is an $S$-factor maximum at very low energies for systems with a positive fusion $Q$ value is an experimentally challenging question.Purpose: Our aim has been to search for evidence of fusion hindrance in $^{12}\mathrm{C}+^{24}\mathrm{Mg}$ which is a medium-light system with positive $Q$ value for fusion, besides the heavier cases where hindrance is recognized to be a general phenomenon. $^{12}\mathrm{C}+^{24}\mathrm{Mg}$ is very close to the $^{16}\mathrm{O}+^{16}\mathrm{O}$ and $^{12}\mathrm{C}+^{12}\mathrm{C}$ systems that are important for the late evolution of heavy stars.Methods: The experiment has been performed in inverse kinematics using the $^{24}\mathrm{Mg}$ beam from the XTU Tandem accelerator of LNL in the energy range 26--52 MeV with an intensity of 4--8 pnA. The targets were $^{12}\mathrm{C}$ evaporations $50\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\mathrm{g}/{\mathrm{cm}}^{2}$ thick, isotopically enriched to $99.9%$. The fusion-evaporation residues were detected at small angles by a $E\ensuremath{-}\mathrm{\ensuremath{\Delta}}E$-ToF detector telescope following an electrostatic beam deflector.Results: Previous measurements of fusion cross section for $^{12}\mathrm{C}+^{24}\mathrm{Mg}$ were limited to above-barrier energies. In the present experiment the excitation function has been extended down to $\ensuremath{\simeq}15\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{b}$ and it appears that the $S$ factor develops a clear maximum vs energy, indicating the presence of hindrance. This is the first convincing evidence of an $S$ factor maximum in a medium-light system with a positive fusion $Q$ value. These results have been fitted following a recently suggested method and a detailed analysis within the coupled-channels model that has been performed using a Woods-Saxon potential and including the ground state rotational band of $^{24}\mathrm{Mg}$. The coupled-channels calculations give a good account of the data near and above the barrier but overpredict the cross sections at very low energies.Conclusions: The hindrance phenomenon is clearly observed in $^{12}\mathrm{C}+^{24}\mathrm{Mg}$, and its energy threshold is in reasonable agreement with the systematics observed for several medium-light systems. The fusion cross sections at the hindrance threshold show that the highest value (${\ensuremath{\sigma}}_{s}=1.6\phantom{\rule{0.28em}{0ex}}\mathrm{mb}$) is indeed found for this system. Therefore it may even be possible to extend the measurements further down in energy to better establish the position of the $S$-factor maximum.