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The aim of this investigation is to reveal the structure of 150Sm by measuring for the first time a rather complete set of energy levels of this nucleus up to 4 MeV and determine the total angular momentum of the states. The study was carried out at the 14 MV Tandem Accelerator of the Munich universities by measuring complete angular distributions for states up to 4 MeV excited in the direct two-neutron transfer reaction 152Sm(p,t)150Sm at an incident energy of 22 MeV. Emphasis was put on determining the 0+ excited states, which are some of the most important excitations in the rare-earth region. Up to now only three 0+ levels are known in 150Sm, and investigating the distribution of energy and intensity of these excited states also at higher excitation energy might reveal the main contributions in the wave functions of this nucleus.

We developed the isotope-specific Computed Tomography imaging technique based on the Nuclear Resonance Fluorescence absorption method at BL1U of UVSOR-III by using high flux and quasi-monochromatic gamma-ray beam for a sample target containing two enriched lead isotope rods (206Pb and 208Pb). The maximum Laser Compton Scattering gamma-ray beam energy was 5528 keV and the gamma-rays flux was greater than 107 photons/s after collimation. A two-dimensional image of 208Pb isotope distribution was selectively obtained using an exited state in 208Pb at 5512 keV.

Excited states in the deformed nucleus $^{158}$Gd have been studied in the (p,t) reaction by using the Munich Tandem and Q3D spectrograph. 30 new excited 0$^+$ states (three tentative) have been assigned up to the 4.3 MeV excitation energy. The total number of 34 excited 0$^+$ states (four tentatively assigned) in a deformed nucleus, close to a complete level scheme, offers a new opportunity to test nuclear models and obtain more information on the structure of these special states.

The structure of $^{34}$Si was studied through $\gamma$ spectroscopy separately in the $\beta^-$ decays of $^{34}$Mg and $^{34}$Al at the ISOLDE facility of CERN. Different configurations in $^{34}$Si were populated independently from the two recently identified $\beta$-decaying states in $^{34}$Al having spin-parity assignments $J^\pi = 4^-$ dominated by the normal configuration $\pi (d_{5/2})^{-1} \otimes \nu (f_{7/2})$ and $J^\pi = 1^+$ by the intruder configuration $\pi (d_{5/2})^{-1} \otimes \nu (d_{3/2})^{-1}(f_{7/2})^{2}$. The paper reports on spectroscopic properties of $^{34}$Si such as an extended level scheme, spin and parity assignments based on log($ft$) values and $\gamma$-ray branching ratios, absolute $\beta$ feeding intensities and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of $^{34}$Si. Large scale shell-model calculations using the {\sc sdpf-u-mix} interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of {\sc sdpf-u-mix}, the $N=20$ shell gap, the level of mixing between normal and intruder configurations for the 0$_1^+$, 0$_2^+$ and 2$_1^+$ states and the absence of triaxial deformation in $^{34}$Si.

The structure of $^{34}$Si was studied through $\gamma$ spectroscopy separately in the $\beta^-$ decays of $^{34}$Mg and $^{34}$Al at the ISOLDE facility of CERN. Different configurations in $^{34}$Si were populated independently from the two recently identified $\beta$-decaying states in $^{34}$Al having spin-parity assignments $J^\pi = 4^-$ dominated by the normal configuration $\pi (d_{5/2})^{-1} \otimes \nu (f_{7/2})$ and $J^\pi = 1^+$ by the intruder configuration $\pi (d_{5/2})^{-1} \otimes \nu (d_{3/2})^{-1}(f_{7/2})^{2}$. The paper reports on spectroscopic properties of $^{34}$Si such as an extended level scheme, spin and parity assignments based on log($ft$) values and $\gamma$-ray branching ratios, absolute $\beta$ feeding intensities and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of $^{34}$Si. Large scale shell-model calculations using the {\sc sdpf-u-mix} interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of {\sc sdpf-u-mix}, the $N=20$ shell gap, the level of mixing between normal and intruder configurations for the 0$_1^+$, 0$_2^+$ and 2$_1^+$ states and the absence of triaxial deformation in $^{34}$Si.

Excited states in the $^{158}\mathrm{Eu}$ nucleus have been determined with the $^{160}\mathrm{Gd}(d,\ensuremath{\alpha})^{158}\mathrm{Eu}$ reaction, studied at an incident energy of 18.0 MeV with the Munich tandem and Q3D spectrograph. More than 50 excited states have been determined up to 1.6 MeV excitation, some of them corresponding to states previously observed in the ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of $^{158}\mathrm{Sm}$. The number of levels found in this nucleus at low excitation energies follows the systematic trend of the level densities in the other isotopes with mass 152--156.

Compton γ -ray sources have been in operation for over 30 years with new facilities being under construction or proposed. The gamma beam system under implementation at the Extreme Light Infrastructure - Nuclear Physics facility in Romania will deliver brilliant γ -ray beams with energies up to 19.5 MeV. Several instruments for measuring the parameters of the γ -ray beam are under development at ELI-NP. One of these instruments based on a High Purity Germanium detector is routinely used for beam energy measurements at other facilities. Here we investigate the use of a High Purity Germanium detector to continuously monitor the intensity of the ELI-NP gamma beam by measuring the inelastic scattering of photons. This method relies on both experimental and simulated data and it has been successfully tested during a recent experiment at the High Intensity γ -ray Source facility.

Excited states in Sn-133 were investigated through the beta decay of In-133 at the ISOLDE facility. The ISOLDE Resonance Ionization Laser Ion Source (RILIS) provided isomer-selective ionization for In-133, allowing us to study separately, and in detail, the beta-decay branch of In-133 J(pi)= (9/2(+)) ground state and its J(pi) = (1/2(-)) isomer.Thanks to the large spin difference of the two beta-decaying states of In-133, it is possible to investigate separately the lower and higher spin states in the daughter, Sn-133, and thus to probe independently different single-particle and single-hole levels. We report here new gamma transitions observed in the decay of In-133, including those assigned to the deexcitation of the neutron-unbound states.

© 2019 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Excited states in Sn133 were investigated through the β decay of In133 at the ISOLDE facility. The ISOLDE Resonance Ionization Laser Ion Source (RILIS) provided isomer-selective ionization for In133, allowing us to study separately, and in detail, the β-decay branch of In133Jπ=(9/2+) ground state and its Jπ=(1/2-) isomer. Thanks to the large spin difference of the two β-decaying states of In133, it is possible to investigate separately the lower and higher spin states in the daughter, Sn133, and thus to probe independently different single-particle and single-hole levels. We report here new γ transitions observed in the decay of In133, including those assigned to the deexcitation of the neutron-unbound states. ispartof: Physical Review C vol:99 issue:2 status: published

International audience; Excited states in $^{133}Sn$ were investigated through the $\beta$ decay of $^{133}In$ at the ISOLDE facility. The ISOLDE Resonance Ionization Laser Ion Source (RILIS) provided isomer-selective ionization for $^{133}In$, allowing us to study separately, and in detail, the β-decay branch of $^{133}In$ J$^{\pi}$=(9/2$^+$) ground state and its J$^{\pi}$=(1/2$^−$) isomer. Thanks to the large spin difference of the two β-decaying states of $^{133}In$, it is possible to investigate separately the lower and higher spin states in the daughter, $^{133}Sn$, and thus to probe independently different single-particle and single-hole levels. We report here new $\gamma$ transitions observed in the decay of $^{133}In$, including those assigned to the deexcitation of the neutron-unbound states.

Two-neutron transfer reactions serve as an important tool for nuclear-structure studies in the neutron-rich part of the nuclear chart. In this paper, we report on the first experimental attempt to populate the excited states of140Ba employing the 2n-transfer reaction138Ba(18O,16O)140Ba. 140Ba is highly important, as it is placed on the onset of octupole correlations and the lifetimes of its excited states are completely unknown, with the sole exception of the first 2+ state. The experiment was carried out at the Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH) in Magurele, Romania. Lower limits on the lifetimes of the ground state band up to the 8+ state are reported. Furthermore, relative cross-sections regarding the 2n-transfer reaction with respect to the fusion and the total inelastic reaction channels have been deduced. Further investigation directions of the nuclear structure of 140Ba are also discussed. © CopyrightEPLA, 2020.

10 pags., 8 figs., 1 tab.-- Open Access funded by Creative Commons Atribution Licence 4.0, Excited states in Sn133 were investigated through the ß decay of In133 at the ISOLDE facility. The ISOLDE Resonance Ionization Laser Ion Source (RILIS) provided isomer-selective ionization for In133, allowing us to study separately, and in detail, the ß-decay branch of In133J¿=(9/2+) ground state and its J¿=(1/2-) isomer. Thanks to the large spin difference of the two ß-decaying states of In133, it is possible to investigate separately the lower and higher spin states in the daughter, Sn133, and thus to probe independently different single-particle and single-hole levels. We report here new ¿ transitions observed in the decay of In133, including those assigned to the deexcitation of the neutron-unbound states., We acknowledge the support of the ISOLDE Collaboration and technical teams. This work was supported in part by the Polish National Science Center under Contract No. UMO-2015/18/E/ST2/00217 and under Contract No. UMO-2015/18/M/ST2/00523, by the Spanish MINECO via FPA2015-65035-P project, by the Portuguese FCT via CERN/FIS-NUC/0004/2015 and CERN-FIS-PAR-0005-2017 projects. The research leading to these results has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 654002.

Gamow-Teller β decay is forbidden if the number of nodes in the radial wave functions of the initial and final states is different. This Δn = 0 requirement plays a major role in the β decay of heavy neutron-rich nuclei, affecting the nucleosynthesis through the increased half-lives of nuclei on the astrophysical r-process pathway below both Z = 50 (for N > 82) and Z = 82 (for N >126). The level of forbiddenness of the Δn = 1ν1g9/2 → π0g7/2 transition has been investigated from the β− decay of the ground state of 207Hg into the single-proton-hole nucleus 207Tl in an experiment at the ISOLDE Decay Station. From statistical observational limits on possible γ-ray transitions depopulating the π0g7/2−1 state in 207Tl, an upper limit of 3.9 × 10−3% was obtained for the probability of this decay, corresponding to log ft > 8.8 within a 95% confidence limit. This is the most stringent test of the Δn = 0 selection rule to date. peerReviewed

Novel injectable thermosensitive hydrogel formulations with improved both water retention (WR) and drug release profile were prepared by adding dextran (DXT) to poly(N-isopropylacrylamide) (PNIPAM) aqueous solutions as a remedy against the demixing/syneresis phenomenon. The addition of the hydrophilic polysaccharide improved the WR of the hydrogel at 37°C from about 12% in the absence of DXT to about 40–55% out of the initial amount introduced, depending on both PNIPAM and DXT concentrations. Also, the 5-fluorouracil release experiments showed an appreciably reduced “burst effect” for the DXT-containing hydrogels. The shape of the release profiles revealed the presence of two stages, differing each other from the point of view of the drug release rate.

The neutron-rich 144,146 Ba isotopes have been studied recently in terms of their experimental B(E3) values [1,2]. Although featuring large uncertainties, the results were found to be significantly larger than any theoretical calculation. Similar questions exist for the slightly lighter isotope 140 Ba, which is particularly interesting since it is located at the onset of octupole correlations. The lifetimes of the lower-lying states are completely unknown, with the sole exception of the first 2 + state [3]. In this work, we report on the outcome of a short test run, attempting to populate the states of interest using the 138 Ba( 18 O, 16 O) 140 Ba reaction. The experiment was carried out at IFIN-HH using a specially manufactured nat Ba target sandwiched between two Au layers. This was considered imperative due to Barium's quick oxidation in air. Four beam energies (61,63,65,67 MeV) below the Coulomb barrier have been tested. The subsequent decay was measured using the Bucharest ROSPHERE array, consisting of 15 Ge detectors and 10 LaBr­ 3 (Ce) scintillators. The preliminary results from the test run report on the level population strengths and the limits in lifetime measurements, which are expected to provide new information on the structural effects in neutron-rich barium isotopes, especially regarding quadrupole and octupole degrees of freedom. The _ndings are also expected to act as stringent tests to theoretical modeling in this mass regime.

A customizable and cost-efficient particle-detection system for transfer experiments at ROSPHERE has been designed and tested. Results from the commissioning experiment employing the 2 n -transfer reaction 94Zr(18O, 16O)96Zr are presented and discussed. The device allows for an efficient suppression of contributions from fusion-evaporation reactions and an improvement of the peak-to-background ratio by about one order of magnitude. The construction, characteristics, and performance are presented and further developments are outlined.

International audience; A proton inelastic scattering experiment on a 57Fe target was performed at the 9 MV TANDEM facility of Horia Hulubei-National Institute of Physics and Nuclear Engineering, Bucharest-Măgurele, Romania. The purpose was to determine the γ-production cross sections of the transitions observed in the 57Fe(p, p’γ)57Fe reaction. The detection system consisted of 4 HPGe detectors for detection and a Faraday cup for beam integration. The proton energy was varied from 5 to 16 MeV, in 1-MeV steps. In the current analysis, experimental cross sections were determined only for the high-volume detectors, placed at 110◦ and 150◦ with respect to the beam axis. This work presents the data analysis procedure and the preliminary experimental cross sections for the most intense transitions decaying from the first seven excited states in 57Fe. The results are compared with TALYS 1.9 theoretical calculations performed using default input parameters.

12 pags., 11 figs., 3 tabs. -- Open Access funded by Creative Commons Atribution Licence 4.0, The occurrence of octupolar shapes in the Ba isotopic chain was recently established experimentally up to N = 90. To further extend the systematics, the evolution of shapes in the most neutron-rich members of the Z = 56 isotopic chain accessible at present, Ba-148,Ba-150, has been studied via beta decay at the ISOLDE Decay Station. This paper reports on the first measurement of the positive-and negative-parity low-spin excited states of 150Ba and presents an extension of the beta-decay scheme of Cs-148. Employing the fast timing technique, half-lives for the 2(1)(+) level in both nuclei have been determined, resulting in T-1/2 = 1.51(1) ns for Ba-148 and T-1/2 = 3.4(2) ns for Ba-150. The systematics of low-spin states, together with the experimental determination of the B(E2 : 2(+) -> 0(+)) transition probabilities, indicate an increasing collectivity in Ba148-150, towards prolate deformed shapes. The experimental data are compared to symmetry conserving configuration mixing (SCCM) calculations, confirming an evolution of increasingly quadrupole deformed shapes with a definite octupolar character., The IDS Collaboration acknowledges financial support from Istituto Nazionale di Fisica Nucleare, the Italian “Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale” (PRIN), contract 2001024324 01302; the European Union seventh framework through ENSAR, contract 262010; the European Unions Horizon 2020 Framework research and innovation program under grant agreement 654002 (ENSAR2); the FATIMA-NuPNET network via the PRI-PIMNUP-2011-1338 project; the Romanian IFA grant CERN/ISOLDE and Romanian PN-II-RU-TE-2014-4-2003; the Spanish MINECO projects, reference numbers FPA2013- 41467-P, FPA2015-64969-P, FPA2015-65929, and FIS2015- 63770; Spanish grants FIS-2014-53434-P MINECO and Programa Ramon y Cajal 2012 No. 11420, MINECO grant IJCI-2014-19172, and the MINECO project FPA2014-52823- C2-1-P; the German BMBF under contract 05P15PKCIA, contract 05P15PKFNA, and “Verbundprojekt 05P2015,” the FWO-Vlaanderen (Belgium); and the IAP Belgian Science Policy (BriX network P7/12). V.Ch. and Z.P. acknowledge support by the Polish grant of Narodowe Centrum Nauki, no. 2015/18/M/ST2/00523.

6 pags., 3 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0. -- Presented at the XXXV Mazurian Lakes Conference on Physics, Piaski, Poland, September 3–9, 2017., Excited states in the neutron-rich isotope 133Sn were studied via the ß decay of 133In. Isomer selective ionization using the ISOLDE RILIS enabled the ß decays of 133Ings (I¿ = 9=2+) and 133mIn (II¿ = 1=2-) to be studied independently for the first time. A description of the experimental setup at the ISOLDE Decay Station is presented together with preliminary results from the experiment., This work was supported in part by the National Science Centre, Poland (NCN) under contracts No. UMO-2015/18/E/ST2/00217 and No. UMO- 2015/18/M/ST2/00523, by the Spanish MINECO via FPA2015-65035-P project and by the Portuguese FCT via CERN/FIS-NUC/0004/2015 project.

The properties of excited states in the neutron-rich nucleus 194Os have been investigated using the 192Os(18O,16O)194Os reaction with an 80 MeV beam provided by the IFIN-HH Laboratory, Bucharest. Discrete γ -ray decays from excited states have been measured using the hybrid HPGe-LaBr3(Ce) array RoSPHERE. The current work identifies a number of previously unreported low-lying nonyrast states in 194Os as well as the first measurement of the half-life of the yrast 2+ state of 302(50) ps. This is equivalent to a B(E2 : 2+ → 0+) = 45(16) W.u. and intrinsic quadrupole deformation of βeff = 0.14(1). The experimental results are compared with Hartree-Fock-Bogoliubov–interacting-boson-model calculations and are consistent with a reduction in a quadrupole collectivity in Os isotopes with increasing neutron number.

The properties of excited states in the neutron-rich nucleus 194Os have been investigated using the 192Os(18O,16O)194Os reaction with an 80 MeV beam provided by the IFIN-HH Laboratory, Bucharest. Discrete γ -ray decays from excited states have been measured using the hybrid HPGe-LaBr3(Ce) array RoSPHERE. The current work identifies a number of previously unreported low-lying nonyrast states in 194Os as well as the first measurement of the half-life of the yrast 2+ state of 302(50) ps. This is equivalent to a B(E2 : 2+ → 0+) = 45(16) W.u. and intrinsic quadrupole deformation of βeff = 0.14(1). The experimental results are compared with Hartree-Fock-Bogoliubov–interacting-boson-model calculations and are consistent with a reduction in a quadrupole collectivity in Os isotopes with increasing neutron number.

The properties of excited states in the neutron-rich nucleus 194Os have been investigated using the 192Os(18O , 16O) 194Os reaction with an 80 MeV beam provided by the IFIN-HH Laboratory, Bucharest. Discrete γ -ray decays from excited states have been measured using the hybrid HPGe-LaBr3(Ce) array RoSPHERE. The current work identifies a number of previously unreported low-lying nonyrast states in 194Os as well as the first measurement of the half-life of the yrast 2+ state of 302(50) ps. This is equivalent to a B(E2:2+ → 0+) = 45(16) W.u. and intrinsic quadrupole deformation of βeff = 0.14(1). The experimental results are compared with Hartree-Fock- Bogoliubov–interacting-boson-model calculations and are consistent with a reduction in a quadrupole collectivity in Os isotopes with increasing neutron number

R. Lica et al. -- 6 pags., 3 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0, The β- decay of Mg34 was used to study the Al34 nucleus through γ spectroscopy at the Isotope Separator On-Line facility of CERN. Previous studies identified two β-decaying states in Al34 having spin-parity assignments Jπ=4- dominated by the normal configuration π(d5/2)-1 - ν(f7/2) and Jπ=1+ by the intruder configuration π(d5/2)-1 - ν(d3/2)-1(f7/2)2. Their unknown ordering and relative energy have been the subject of debate for the placement of Al34 inside or outside the N=20 >island of inversion.> We report here that the 1+ intruder lies only 46.6 keV above the 4- ground state. In addition, a new half-life of T1/2=44.9(4)ms, that is twice as long as the previously measured 20(10) ms, has been determined for Mg34. Large-scale shell-model calculations with the recently developed sdpf-u-mix interaction are compared with the new data and used to interpret the mechanisms at play at the very border of the N=20 island of inversion., This Rapid Communication was partially supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS-UEFISCDI Project No. PN-II-RU-TE-2014-4-1455, the Romanian IFA Grant CERN/ISOLDE, by FWO-Vlaanderen (Belgium), by GOA/2010/010 (BOF KU Leuven), and by the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12). Support from the U.K. Science and Technology Facilities Council, the European Union Seventh Framework through ENSAR (Contract No. 262010), the MINECO (Spain) Grants No. FPA2015-64969- P, No. FPA2014-57196, and No. FPA2015-65035-P, Programme “Centros de Excelencia Severo Ochoa” Program No. SEV-2012-0249, the German BMBF under Contract No. 05P15PKCIA (ISOLDE), and “Verbundprojekt 05P2015” also is acknowledged.

The Zirconium isotopes across the N=56,58 neutron sub­shell closures have been of special interest since years, sparked by the near doubly-magic features of 96Zr and the subsequent rapid onset of collectivity with a deformed ground-state structure already in 100Zr. Recent state-of-the-art shell model approaches did not only correctly describe this shape-phase transition in the Zr isotopic chain, but alsothe coexistence of non-collective structures and pronounced collectivity especially in 96,98Zr. Theisotope 98Zr is located on the transition from spherical to deformed ground state structures. We summarize recent experimental work to obtain the B(E2) excitation strengths of the first 2+ state of98Zr, including a new experiment employing the recoil-distance Doppler-shift method following a two-neutron transfer reaction.