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Background: Neutron-rich nuclei in the $\mathrm{A}\ensuremath{\approx}140--160$ mass region provide valuable information on nuclear structure such as quadrupole- and octupole-shape coexistence and the evolution of the collectivity. These nuclei have also a nuclear engineering interest because they contribute to the total decay heat after a fission burst. The information concerning $^{145}\mathrm{La}$ is very limited.Purpose: The study of low-spin states in $^{145}\mathrm{La}$ will provide a more detailed level scheme and enable the determination of the half-lives of the excited states.Methods: Low-spin excited states in $^{145}\mathrm{La}$ have been investigated from the $^{145}\mathrm{Ba}\phantom{\rule{4pt}{0ex}}{\ensuremath{\beta}}^{\ensuremath{-}}$ decay. The $^{145}\mathrm{Ba}$ nuclei were directly produced by photofission in the ALTO facility or obtained from the ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of $^{145}\mathrm{Cs}$ also produced by photofission. Gamma spectroscopy and fast-timing techniques were used.Results: A new level scheme was proposed including 67 excited levels up to about 3 MeV and 164 transitions. Half-lives in the few-nanosecond range were measured for the first excited states. Configurations for levels up to $\ensuremath{\approx}600$ keV were discussed.Conclusions: The available information on the low-spin states of $^{145}\mathrm{La}$ has been modified and considerably extended. The analysis of the properties of the first excited states, such as excitation energies, decay modes, log $\mathit{\text{ft}}$ values, reduced transition probabilities, and Weisskopf hindrance factors, has enabled the identification of the first members of the bands corresponding to the ${g}_{7/2},$ ${d}_{5/2},$ and ${h}_{11/2}$ proton configurations.

International audience; In the context of radioactive ion beams, fission targets, often based on uranium compounds, have been used for more than 50 years at isotope separator on line facilities. The development of several projects of second generation facilities aiming at intensities two or three orders of magnitude higher than today puts an emphasis on the properties of the uranium fission targets. A study, driven by Institut de Physique Nucléaire d'Orsay (IPNO), has been started within the SPIRAL2 project to try and fully understand the behavior of these targets. In this paper, we have focused on five uranium carbide based targets. We present an off-line method to characterize their fission product release and the results are examined in conjunction with physical characteristics of each material such as the microstructure, the porosity and the chemical composition.

The national project for the measurement of radiocarbon includes different scientific partners for the accelerator named ARTEMIS (French acronym for Accélérateur pour la Recherche en sciences de la Terre, Environnement, Muséologie Installé à Saclay), available to the scientific community since 2004 (Cottereau et al. 2007). The French Ministry of Culture uses this accelerator mass spectrometry (AMS) facility at the request of archaeologists or curators of museums or of historical monuments. For the preparation of some samples, a laboratory has been installed at the Centre of Research and Restoration of the Museums of France, located in the Louvre Palace. In this report, the first data carried out on vegetal samples from museum objects or archaeological remains, dates are presented in terms of yr BP (before AD 1950).

The new facility Artemis was installed in 2003 in Saclay, France. This 3MV NEC Pelletron is dedicated to high-precision radiocarbon measurements for French 14C laboratories. We will present information on Artemis along with our sample preparation methods. Results from measurements on some intercalibration samples will be given along with the values of measured blanks. Finally, we report on some problems we have encountered when measuring sputter cathodes with high CH− outputs.

Systematic off-line fluorination studies on all the stable lanthanide isotopes have been performed. The results are presented as a function of various parameters such as the target temperature, the type of ion source used (hot plasma or surface ionization) and the quantity of CF4 introduced. The first on-line measurements allowed us to determine the optimal experimental conditions for producing radioactive lanthanide isotopes. Fil: Roussière, B.. Université Paris Sud; Francia Fil: Deloncle, I.. Université Paris Sud; Francia Fil: Barrè Boscher, N.. Université Paris Sud; Francia Fil: Cardona, Maria Angelica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; Argentina Fil: Mhamed, M. Cheikh. Université Paris Sud; Francia Fil: Corbin, T.. Université Paris Sud; Francia Fil: Cottereau, E.. Université Paris Sud; Francia Fil: Croizet, H.. Université Paris Sud; Francia Fil: Dimitrov, B.. Institute For Nuclear Research And Nuclear Energy Bulgarian Academy Of Sciences; Bulgaria Fil: Essabaa, S.. Université Paris Sud; Francia Fil: Gavrilov, G.. Institute For Nuclear Research And Nuclear Energy Bulgarian Academy Of Sciences; Bulgaria Fil: Gottardo, A.. Université Paris Sud; Francia Fil: Goutev, N.. Institute For Nuclear Research And Nuclear Energy Bulgarian Academy Of Sciences; Bulgaria Fil: Guillot, J.. Université Paris Sud; Francia Fil: Hojman, Daniel Leonardo. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lau, C.. Université Paris Sud; Francia Fil: Roccia, S.. Université Paris Sud; Francia. Centre de Sciences Nucleaires Et de Sciences de la Matiere; Francia Fil: Tusseau-Nenez, S.. Université Paris Sud; Francia Fil: Verney, D.. Université Paris Sud; Francia Fil: Yavahchova, M.. Institute For Nuclear Research And Nuclear Energy Bulgarian Academy Of Sciences; Bulgaria

The γ-ray de-excitations following the β-decay of 83Ga and the β-n decay of 84Ga have been studied. The radioactive species were produced using the PARRNe on-line mass-separator installed at the IPN Orsay Tandem accelerator. Two γ-lines were attributed to 83Ge with the aid of β-γ and γ-γ coincidences. The Z identification of the γ-lines was provided by time analysis of a buid-up/decay cycle. The excited levels of 83Ge can be explained by the coupling of the single neutron state ν2d 5/2 to the first 2+ excitation of the 82Ge core.

The PARRNe (Production d'Atomes Radioactifs Riches en Neutrons) experimental program has been part of the recent R&D efforts for the design of the SPIRAL2 project at GANIL. The PARRNe2 set-up installed at IPNOrsay allows the use of the Tandem as a deuteron driver in order to produce mass separated fission fragment beams. The measured fission fragment yields proved to be high enough to undertake a series of beta-decay experiments dedicated at studying the structure of proton-deficient nuclei close to N=50. We report here on two such experiments, the first being dedicated at the observation of the decay of 83Ga->83Ge (Z=32, N=51), 84Ga->84Ge (Z=32, N=52) and the second of the decay of 81Zn->81Ga (Z=31, N=50) allowing for the fist time the identification of a few gamma lines with transitions in the daughter nuclei thus providing the material for a preliminary glimpse of their structure.

In the framework of the PARRNe program (Production d’Atomes Radioactifs Riches en Neutrons) of IPN Orsay, various techniques are currently used to characterize the release properties of elements of interest from a UCX target. On-line studies have been carried out with two plasma ion sources: a Nier–Bernas and a hot plasma ISOLDE-type (the ISOLDE collaboration kindly supplied us a MK5 ion source for these studies). In parallel, the analysis of the chemical and structure properties of some UCX samples as function of heating conditions has been carried out. Such data are essential to determine optimal conditions for the production of isotopes by the isotope separator on-line (ISOL) technique. First results are presented here for Kr and Ag. Investigations for other kinds of fission targets are planned.

International audience; The Andromede project is the center of a multi-disciplinary team which will build a new instrument for surface modification and analysis using the impact of probes from hydrogen to nano-particles (Au400+4) in the MeV range. For this new instrument a series of atomic, polyatomic, molecular and nano-particle ion beams will be delivered using two ion sources in tandem, a liquid metal ion source and an electron cyclotron resonance source. The delivered ion beams will be accelerated to high energy with a 4 MeV van de Graaff type accelerator. By using a suite of probes in the MeV energy range, ion beam analysis techniques, MeV atomic and cluster secondary ion mass spectrometry can all be performed in one location. A key feature of the instrument is its ability to produce an intense beam for injection into the accelerator. The commissioning of the two sources shows that intense beams from atomic ions to nano-particles can be delivered for subsequent acceleration. The calculations and measurements for the two sources are presented.

The latest results of the research and development program Production d'Atomes Radioactifs Riches en Neutrons (PARRNe) at Institut de Physique Nucleaire (IPN) Orsay are presented. The production of neutron rich isotopes by fast neutron induced fission in a liquid depleted uranium target was measured. A comparison of the production rates with a uranium carbide (UCx) target is given.

Single crystals of LiNbO 3 (Y-cut orientation) were irradiated at room temperature with 3 MeV C 6 + and 2.4 MeV C 8 + clusters provided by CSNSM “ARAMIS” accelerator. The electronic stopping power was about 6.5 keV nm −1 in both cases. The fluences extended from 10 10 to 4 × 10 12 C 6 + or C 8 + cm −2 . Rutherford Backscattering Spectrometry in Channeling geometry (RBS/C) revealed the presence of extended defects, which cannot be due solely to nuclear stopping and which we ascribe to the high density of electronic energy associated with the correlated electronic stopping of the cluster components. The RBS/C analysis, providing a lattice disorder profile, confirms this interpretation: the damaged thickness closely corresponds to the cluster components correlation length (between 50 and 100 nm). The fluence evolutions of the disorder ratio, measured at the sample surface for C 6 and C 8 projectiles, correspond to damage cross sections close to 1.8 × 10 −13 cm 2 in the two cases.

Aramis is a home built multipurpose 2 MV electrostatic tandem accelerator. A large variety of ions are available for high energy implantation. Characterization possibilities are also quite large in the Van de Graaff mode owing to the Penning positive ion source in the terminal. A second beam line is now available that sends the beam into the target chamber of the 200 kV medium current implanter. We will provide a progress report on the machine and present some results regarding in situ studies of multilayer mixing and implanted silicide layers

$\ensuremath{\gamma}$-rays following the $\ensuremath{\beta}$ and $\ensuremath{\beta}\text{\ensuremath{-}}n$ decays of the very neutron rich ${}_{31}^{84}{\mathrm{Ga}}_{53}$ produced by the photofission of $^{238}\mathrm{U}$ have been studied at the newly built ISOL facility of IPN Orsay: ALTO. Two activities were observed and assigned to two $\ensuremath{\beta}$-decaying states: $^{84}\mathrm{Ga}$${}^{g}$, ${I}^{\ensuremath{\pi}}=({0}^{\ensuremath{-}})$ and $^{84}\mathrm{Ga}$${}^{m}$, ${I}^{\ensuremath{\pi}}=({3}^{\ensuremath{-}},{4}^{\ensuremath{-}})$. Excitation energies of the ${2}_{1}^{+}$ and ${4}_{1}^{+}$ states of ${}_{32}^{84}{\mathrm{Ge}}_{52}$ were measured at $E({2}_{1}^{+})=624.3$ keV and $E({4}_{1}^{+})=1670.1$ keV. Comparison with HFB $+$ GCM calculations allows to establish the collective character of this nucleus. The excitation energy of the $1/{2}_{1}^{+}$ state in ${}_{32}^{83}{\mathrm{Ga}}_{51}$ known to carry a large part of the neutron $3{s}_{1/2}$ strength was measured at $247.8$ keV. Altogether these data allow to confirm the new single particle state ordering which appears immediately after the double $Z=28$ and $N=50$ shell closure and to designate $^{78}\mathrm{Ni}$ as a fragile and easily polarized doubly-magic core.

NESTER ACC; The release properties of a UCx thick target associated with a hot plasma ion source have been studied. Measurements have been performed for various elements: Kr, Ag, Sn, I and Xe. The analysis is made assuming pure diffusion or pure effusion as the release processes. The results obtained are compared to the data available in the literature.

Laser spectroscopy measurements have been carried out on the neutron-rich tin isotopes with the COMPLIS experimental setup. Using the $5{s}^{2}5{p}^{2\phantom{\rule{0.3em}{0ex}}3}{P}_{0}\ensuremath{\rightarrow}5{s}^{2}5p6s\phantom{\rule{0.3em}{0ex}}{}^{3}{P}_{1}$ optical transition, hyperfine spectra of $^{126\ensuremath{-}132}\mathrm{Sn}$ and $^{125,127,129\ensuremath{-}131}\mathrm{Sn}{}^{m}$ were recorded for the first time. The nuclear moments and the mean square charge radius variation ($\ensuremath{\delta}\ensuremath{\langle}{r}_{c}^{2}\ensuremath{\rangle}$) were extracted. From the quadrupole moment values, these nuclei appear to be spherical. The magnetic moments measured are thus compared with those predicted by spherical basis approaches. From the measured $\ensuremath{\delta}\ensuremath{\langle}{r}_{c}^{2}\ensuremath{\rangle}$, the absolute charge radii of these isotopes were deduced in particular that of the doubly magic $^{132}\mathrm{Sn}$ nucleus. The comparison of the results with several mean-field-type calculations have shown that dynamical effects play an important role in the tin isotopes.

Laser spectroscopy measurements have been carried out on the very neutron-rich tin isotopes with the COMPLIS experimental setup. Using the 5s 2 5p 2 3 P 0 → 5s 2 5p6s 3 P 1 optical transition, hyperfine spectra of 126–132 Sn and 125 m ,127 m ,129 m –131 m Sn where recorded for the first time. The variation of the mean square charge radius ( δ 〈 r 2 〉 ) between these nuclei and the nuclear moments of the isomers and the odd isotopes were thus measured. From the quadrupole moments values, all these nuclei appear to be spherical. The experimental magnetic moments are thus compared with the Schmidt values calculations. Moreover, the measured δ 〈 r 2 〉 are compared with several mean field calculations.

In this paper, we present a description of ARAMIS, the 2 MV high current implanter that we are building in our laboratory. The different parts of the machine are described with an emphasis on the original aspects of the machine. The present status of the construction is given.

Recent isotope separations at the electromagnetic separator PARIS [1] for the preparation of thin targets of highly enriched isotopes with thicknesses up to the region of mg/cm2 are examined. Problems related to chemical purity, deposition rate, sputtering of the target and internal stress in the target are described along with the techniques used to overcome them. These techniques involve the choice of the charge material, the deposition in the separator of a protective film on the target, atomic mixing in the target and the use of a liquid nitrogen trap in the collector box.

During test runs dedicated to the commissioning of ALTO (Accélérateur Linéaire et Tandem à Orsay), β and β- n decay of the very neutron rich [Formula: see text] could be observed at the tape station installed on-line with the PARRNe mass-separator. γ-lines observed in the resulting spectra and a careful analysis of the balance of their relative intensities point toward the existence of two β-decaying states in 84 Ga . The decay of these long-lived states appear to feed the [Formula: see text] and [Formula: see text] excited states of [Formula: see text] and the [Formula: see text] state in [Formula: see text] allowing a significant improvement of the knowledge on nuclear structure in the immediate vicinity of 78 Ni .