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Introduction L’obesite est un facteur d’aggravation de l’asthme clairement demontre. L’objectif de notre etude etait d’evaluer la masse grasse (MG) au cours de l’asthme et d’etudier sa relation avec le controle et la qualite de vie (QDV). Methodes Il s’agissait d’une etude transversale qui etait realisee a notre service entre fevrier et juin 2019 et incluant 65 asthmatiques et a l’etat stable. La QDV etait evaluee par le questionnaire AQLQ (asthma quality of life). Une spirometrie et une mesure des parametres anthropometriques (poids, taille, indice de masse corporelle (IMC) et tour de taille (TT)) ont ete realisees. Les valeurs de l’IMC et du TT ont ete comparees aux normes etablies par l’OMS. Une impedencemetrie bioelectrique etait realisee permettant la mesure de la composition corporelle. Un taux de MG normal etait defini par une valeur entre 15 et 20 % chez l’homme et 25 et 30 % chez la femme. Resultats L’âge moyen de la population etait de 48,43 ± 15,78 ans. L’asthme etait modere a severe chez 70 % des patients et non controle dans 45,9 % des cas. Le taux de MG moyen etait de 28 %. Le score moyen du questionnaire AQLQ etait 121 ± 38. Selon l’IMC, une obesite a ete notee dans 46 % des cas, ce taux s’eleve a 60 % en se basant sur le taux de MG. Celle-ci etait significativement correlee aux parametres anthropometriques. Sur le plan fonctionnel, l’IMC et la MG etait significativement et inversement correles a la CVF (p Discussion L’obesite rend l’asthme plus difficile a controler et la reponse au traitement pharmacologique moins spectaculaire. L’alteration de la mecanique thoraco-pulmonaire y joue sans doute un role essentiel, meme si des anomalies biochimiques en relation avec l’inflammation semblent reduire la reponse cellulaire aux corticoides. Conclusion Notre etude a montre que l’IMC et la MG etait associes au controle et la QDV au cours de l’asthme. La perte de poids doit constituer un objectif therapeutique primordial chez les sujets obeses asthmatiques.

The Transnational Access facility ALTO (TNA07-ENSAR/FP7) has been commissioned and received from the French safety authorities, the operation license. It is allowed to run at nominal intensity to produce 1011 fissions/s in a thick uranium carbide target by photo-fission using a 10 μA, 50 MeV electron beam. In addition the recent success in operating the selective laser ion source broadens the physics program with neutron-rich nuclear beams possible at this facility installed at IPN Orsay. The facility also aims at being a test bench for the SPIRAL2 project. In that framework an ambitious R&D program on the target ion source system is being developed.

The Institute of Nuclear Physics at Orsay (IPN-Orsay) has always been a major player in building accelerators for nuclear physics. Already at the time when the first synchrocyclotron had been built at CERN, IPN-Orsay had been operating and exploiting its first accelerator (a synchrotron that had been built by Frederic Joliot and around which the institute was founded). During the 1990s the phasing out of two of the IPN accelerators, the heavy-ion Linac + cyclotron system ALICE and the proton synchrocyclotron, was done timely with GANIL reaching its full performances. IPN Orsay was and still is a key player both during the construction and the exploitation of GANIL facilities. Later on and after building and delivering the superconducting cyclotron AGOR to KVI, the institute started a steady R&D program on ISOL production techniques, which is a long-standing tradition of the institute. It is for instance worth reminding that ISOL techniques were extensively developed at the synchrocyclotron of Orsay during...

International audience; The ALTO facility consists of two accelerators in the same area. A Tandem accelerator dedicated to stable (ions and cluster) beam physics and a linear electron accelerator dedicated to the production of radioactive beams. This gives a unique opportunity to have in the same place cluster beams for interdisciplinary physics and stable and radioactive beams for astrophysics and nuclear physics.

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.

International audience; In the framework of a R&D program aiming to develop uranium carbide (UCx) targets for radioactive nuclear beams, the Institut de Physique Nucléaire d’Orsay (IPNO) has developed an experimental setup to characterize the release of various fission fragments from UCx samples at high temperature. The results obtained in a previous study have demonstrated the feasibility of the method and started to correlate the structural properties of the samples and their behavior in terms of nuclear reaction product release. In the present study, seven UCx samples have been systematically characterized in order to better understand the correlation between their physicochemical characteristics and release properties. Two very different samples, the first one composed of dense UC and the second one of highly porous UCx made of multi-wall carbon nanotubes, were provided by the ActILab (ENSAR) collaboration. The others were synthesized at IPNO. The systems for irradiation and heating necessary for the release studies have been improved with respect to those used in previous studies. The results show that the open porosity is hardly the limiting factor for the fission product release. The homogeneity of the microstructure and the pore size distribution contributes significantly to the increase of the release. The use of carbon nanotubes in place of traditional micrometric graphite particles appears to be promising, even if the homogeneity of the microstructure can still be enhanced

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

Laser spectroscopy based on resonant ionization of laser-desorbed atoms has been used to study the neutron-rich tellurium isotopes with the COMPLIS facility at ISOLDE-CERN. Isotope shifts and hyperfine structures of several neutron-rich Te isotopes: $^{120−136}$Te and $^{123 m−133 m}$Te have been measured. From the hyperfine structure we have extracted magnetic and quadrupole moments. Changes in the mean square charge radii have been deduced and their comparison with the known data for the other elements near Z = 50 is presented. The experimental $\delta$ values are compared with those obtained from relativistic mean field calculations.

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 ALTO project (Accélérateur Linéaire auprès du Tandem d'Orsay) will provide an electron beam available at IPN Orsay at the end of 2005. The maximum energy will be 50 MeV with a maximum average intensity of 10 $\mu$A. It will be used for photofission in U$C_x$ targets. With the same target as that already used on the PARRNE set up it will be possible using ALTO to induce up to $10^11$ fissions/s instead of $10^9$ previously obtained with the 26 MeV/1 $\mu$A deuteron beam. Several ion sources will be adapted on the set up: ISOLDE FEBIAD type, surface ionization, laser,.... Moreover the electron beam could be used for other applications. Calculation about fission, energy deposition and dose rate will be presented, as well as the target-ion source adaptation on the PARRNE facility. For the SPIRAL 2 project planned at GANIL for 2008, the fission of $^{238}$U in uranium carbide target will be induced by a neutron flow created by bombarding a carbon converter with a 40 MeV high intensity deuteron beam. The target has been designed to reach more than $10^13$ fissions/s with a good release time. Calculation and technical considerations used to optimize the target design are detailed. One of main difficulties for this target is to maintain it at high temperature (more than 2000 °C) during 3 months. A tantalum oven has been studied and a prototype is under test at IPN Orsay. Some R&D studies on a high density target are in progress in collaboration with PNPI Gatchina and INFN Legnaro.

In the framework of the EURISOL project, the production of neutron-rich isotopes of rubidium and cesium has been studied. The intensities of mass-separated beams of rubidium and cesium isotopes generated from a thick 238 UC x target connected to a surface ionizer have been measured. The release properties of 140 Cs and 91 Rb have been investigated. The obtained results allowed us to determine the relative fission yields of rubidium and cesium isotopes with high accuracy.

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.

In order to probe neutron rich radioactive noble gases produced by photo-fission, a PARRNe-1 experiment (Production d’Atomes Radioactifs Riches en Neutrons) has been carried out at CERN. The incident electron beam of 50 MeV was delivered by the LIL machine: LEP Injector Linac. The experiment allowed us to compare under the same conditions two production methods of radioactive noble gases: fission induced by fast neutrons and photo-fission. The obtained results show that the use of the electrons is a promising mode to get intense neutron rich ion beams. After the success of this photo-fission experiment, a conceptual design for the installation at IPN Orsay of a 50 MeV electron accelerator close to the PARRNe-2 device has been worked out: ALTO Project. This work has started within a collaboration between IPNO, LAL (Laboratoire de l’Accelerateur Lineaire) and CERN groups.

The release properties of UCx and molten U thick targets associated with a Nier–Bernas ion source have been studied. Two experimental methods are used to extract the release time. Results are presented and discussed for Kr, Cd, I and Xe.

The decay of ${}^{84}$Ga has been reinvestigated at the PARRNe online mass separator of the electron-driven installation ALTO at IPN Orsay. The nominal primary electron beam of 10 $\ensuremath{\mu}$A (50 MeV) on a ${}^{238}$UC${}_{x}$ target in combination with resonant laser ionization were used for the first time at ALTO. Improved level schemes of the neutron-rich ${}^{83,84}$Ge ($Z=32$) isotopes were obtained. The experimental results are compared with the state-of-the-art shell model calculations and discussed in terms of collectivity development in the natural valence space outside the ${}^{78}$Ni core.

$\ensuremath{\gamma}$-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.

A diode-pumped Nd:Lanthanum Magnesium Hexaluminate laser was constructed which provides up to 15 mW of single-mode, tunable CW emission at 1083 nm. By appropriately polarizing the narrow-band laser emission (< 10 MHz), the laser can be used to determine the populations of the magnetic substates of the He ( 23S1) atoms. The laser is tuned to one of the absorption peaks of the helium metastable atom by tilting a thin (1 mm) solid, coated etalon placed inside the laser cavity and the absorption is measured. The relative absorption is used to determine the ensemble polarization ; the absolute absorption yields the metastable density.

This report describes arc-lamp pumped, tunable, continuous-wave LNA laser with improved output efficiency, suitable for optical pumping of helium. Using thermal tuning of intracavity etalons instead of angle tuning reduces losses caused by walk-off effects and provides continuous frequency scanning without a significant decrease in laser power. We obtain an output power of 4 W in a linewidth of 2.5 GHz with the laser wavelength tuned to the 1.083 μm absorption line of metastable helium. This result represents a fourfold gain in efficiency compared with conventional tuning by tilting. The laser provides efficient polarization of helium by optical pumping in various applications, such as nuclear spin polarization of 3He and spin-polarized electron sources.

International audience; Production of Rb, Cs and Fr isotopes from uranium carbide targets of a high density has been investigated. The UC target material with a density of 12 g/cm3 was prepared in a form of pellets of 2 mm thickness, 11 mm in diameter and grain dimensions of about 20 microns. Two targets were tested on-line at the same temperature conditions: a) a reference small target with a thickness of 4.5 g/cm2; b) a big massive target with a thickness of 91 g/cm2. The yields and release efficiencies of the nuclides with the half-lives from some minutes to some milliseconds produced from the investigated targets have been presented. A preliminary analysis of the obtained results has shown an increase of the produced nuclide yields proportionally to the target thickness even for very short-lived isotopes 214Fr (T1/2=5 ms) and 219Fr (T1/2=20 ms). One month off-line heating test of a big target at a temperature of 2000 °C has been conducted. The yields and release of Rb, Cs and Fr measured on-line before and after the heating test coincided in the limits of measurement errors that demonstrated the conservation of the developed target unit parameters. The construction of a big target with the mass about 0.7 kg prepared presently at IRIS has been discussed.

The ALTO facility (Accelerateur Lineaire aupres du Tandem d’Orsay) has been built and is now under commissioning. The facility is intended for the production of low energy neutron-rich ion-beams by ISOL technique. This will open new perspectives in the study of nuclei very far from the valley of stability. Neutron-rich nuclei are produced by photofission in a thick uranium carbide target (UC x ) using a 10 μA, 50 MeV electron beam. The target is the same as that already had been used on the previous deuteron based fission ISOL setup (PARRNE [ F. Clapier et al., Phys. Rev. ST-AB (1998) 013501. ]). The intended nominal fission rate is about 10 11 fissions/s. We have studied the adequacy of a thick carbide uranium target to produce neutron-rich nuclei by photofission by means of Monte-Carlo simulations. We present the production rates in the target and after extraction and mass separation steps. The results from Monte-Carlo simulations are compared to experimental data either with the ALTO facility (in the first step of commissioning, i.e. 100 nA of the electron beam current intensity), or with fast-neutron-induced fission generated from a 26 MeV deuteron beam. The results obtained support the suitability of FLUKA simulation code used to describe all the photofission process with an electron beam energy of 50 MeV.

The capture of many electrons by ${\mathrm{Ar}}^{17+}$ ions, at low velocity, near a metallic surface, has been studied. Multiexcited bound states with many electrons in the outermost shells (hollow atoms) have been observed. The surrounding of an ionic excited core by many outermost electrons greatly decreases the lifetimes of the states. This characteristic decrease explains the main striking features of the relaxation of the ions.

The \ensuremath{\beta} decay of the neutron-rich ${}_{30}^{81}{\mathrm{Zn}}_{51}$ has been investigated at the PARRNe mass separator at the IPN Orsay. The sources of $^{81}\mathrm{Zn}$ were produced using the ISOL (Isotopic Separation On Line) technique by the fission of ${}^{\mathrm{nat}}$U exposed to the neutron flux produced by the 26-MeV deuteron beam delivered by the MP-Tandem. With \ensuremath{\gamma} and $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ coincidence measurements, excited levels were attributed to ${}_{31}^{81}{\mathrm{Ga}}_{50}$ for the first time. A partial decay scheme for $^{81}\mathrm{Zn}$ is proposed. The proposed level scheme is well reproduced by shell model calculations using the most recent effective empirical interaction. We show that the structure of this nucleus is consistent with that of the heavier odd-proton $N=50$ isotones within the assumption of strong proton $Z=28$ and neutron $N=50$ effective shell effects. The observed states can be associated to rather simple and clean configurations of three protons placed in the $1{f}_{5/2}$ and $2{p}_{3/2}$ orbits.

International audience; The SPIRAL2 project, currently under construction at GANIL, will include an isotope separator on line based facility for the production and acceleration of radioactive ion beams. A superconducting linear accelerator will accelerate 5 mA deuterons up to 40 MeV and 1 mA heavy ions up to 14.5 MeV/u. These primary beams will be used to bombard both thick and thin targets. We are investigating three different techniques to produce the radioactive ion beams: (1) the neutron induced fission of uranium carbide, (2) the direct interaction of deuterons in a uranium carbide target, and (3) the interaction of a heavy ion beam with a target. All these production systems will be coupled to an ion source. Four kinds of ion sources are foreseen for the ionization of the radioactive atoms: an electron cyclotron resonance ion source, a surface ionization ion source, a forced electron beam induced arc discharge ion source, and a laser ion source depending on the characteristics of the desired radioactive ion beam in terms of intensity, efficiency, purity, etc. A presentation of the SPIRAL2 project and of the different production systems is given.

The production of neutron-rich Ag, In and Sn isotopes from a uranium carbide target of a high density has been investigated at the IRIS facility in the PLOG (PNPI-Legnaro-GANIL-Orsay) collaboration. The UC target material with a density of 12 g/cm3 was prepared by the method of powder metallurgy in a form of pellets of 2 mm thickness, 11 mm in diameter and grain dimensions of about 20 μm. The uranium target mass of 31 g was exposed at a 1 GeV proton beam of intensity 0.05–0.07 μA. For the ionization of the produced species the electron beam–plasma ionization inside the target container (ionizing target) has been used. It was the first experiment when the new high density UC target material was exploited with the electron–plasma ionization. Yields of Sn isotopes have been measured in the target temperature range of (1900–2100) °C. The yields of some Pd, In and Cd isotopes were measured as well to compare to previously measured ones from a high density uranium carbide target having a ceramic-like structure. For the first time a nickel isotope was obtained from a high density UC target.

International audience; Production of on-line mass separated neutron-rich isotopes using fission induced by 1 GeV protons on high-density uranium targets (typically 11 g/cm3) has been investigated for several years at the IRIS facility. Here we review some of the achievements during the years up to 2006 and the perspectives. In particular, we present a comparison of yields in p and n-induced fission, enhancements by secondary neutrons, a comparison with lower-density targets used at PARRNe and ISOLDE for Rb and Cs isotopes and preliminary results obtained with a new UC target material.

The installation of electron Linac at Orsay in the framework of ALTO project is dedicated to fundamental research on exotic nuclei and to other interdisciplinary research subjects, particularly in industrial applications. In fundamental research, the main goal of ALTO is to supply interesting neutron‐rich nuclear beams produced from the photo‐fission process.

International audience; The capacity of uranium carbide target materials of different structure and density for production of neutron-rich and heavy neutron-deficient nuclides have been investigated. The yields of Cs and Fr produced by a 1 GeV proton beam of the PNPI synchrocyclotron and release properties of different targets have been measured. Yields and release efficiencies of Cs and Fr produced from a high density UC target material and from low density UCx prepared by the ISOLDE method at IRIS in the collaboration with PARRNe group from Orsay are compared. The yields from ISOLDE original target are presented for comparison as well.

International audience; The ALTO facility at IPN Orsay is based on a linear electron accelerator (50 MeV, 10μA) dedicated to the production of neutron rich radiactive beams by photofission of a thick uranium carbide target paced on an ISOL line. The construction of the facility has ended in december 2005 and the first on-line tests have been carried out in mid-2006. The production of fission fragments after separation have been measured and are similar to the calculated predictions. Previously, using the same ISOL line, neutron rich nuclei in the vincinity of 78Ni have been produced and studied using the deuteron beam available at the Tandem accelerator in Orsay. First results on excited states in $^{83}_{32}Ge_{51}$ and $^{81}_{31}Ge_{50}$ have been obtained and discussed in the frame of the shell model.

The branching of the ${2}^{+}\ensuremath{\rightarrow}{0}^{+}$ transition in $^{92}\mathrm{Sr}$ has been measured to 0.032(4) per $^{92}\mathrm{Rb}$ decay. It confirms an earlier measurement which was discarded in nuclear data evaluations because of a contradiction with accepted lower log $\mathit{ft}$ limits. The conflict could be solved assuming that close to half of the decay intensity, mostly as high-energy ground-state transitions, is missing in the decay scheme.

International audience; Yields of neutron-rich isotopes produced by the photofission were measured at the ISOL ALTO facility. The identification was achieved by a combined measurement of beta and gamma-rays. Production rates for Xe, Kr, Sn, In and I isotopes are presented here. In parallel, empirical estimations for the yields based on the PARRNe experimental data and the results provided by a very recent FLUKA simulation are presented.

New levels were attributed to $^{81}\_{31}$Ga$\_{50}$ and $^{83}\_{32}$Ge$\_{51}$ which were fed by the $\beta$-decay of their respective mother nuclei $^{81}\_{30}$Zn$\_{51}$ and $^{83}\_{31}$Ga$\_{52}$ produced by fission at the "PARRNe" ISOL set-up installed at the Tandem accelerator of the Institut de Physique Nucl\'eaire, Orsay. We show that the low energy structure of $^{81}\_{31}$Ga$\_{50}$ and $^{83}\_{32}$Ge$\_{51}$ can easily be explained within the natural hypothesis of a strong energy gap at N=50 and a doubly-magic character for $^{78}$Ni., Comment: 2 pages, pdf file, To be published in the Proceedings of "International Symposium on Structure of Exotic Nuclei and Nuclear Forces (SENUF 06)", March 2006, Tokyo, Japan

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 based on resonant ionization of laser-desorbed atoms has been used to study the neutron-rich tellurium isotopes with the COMPLIS facility at ISOLDE-CERN. The isotope shift and the hyperfine structure of several neutron-rich Te isotopes: $^{120–136}$Te and $^{123m–133m}$Te have been measured. From the hyperfine structure and the isotope shift we can extract the magnetic and quadrupole moments and the change in the mean square charge radius respectively. The mean square charge radii of the even-even isotopes have been deduced and their comparison with the known data for the other elements near Z=50 is presented. The experimental $\delta$ is compared with that obtained from the relativistic mean field calculations.

A number of on-line and off-line tests have been performed at the IRIS (investigation of radioactive isotopes at synchrocyclotron) facility in order to develop uranium carbide targets with a high density (11 g/cm3) for the on-line production of neutron-rich isotopes by fission of 238U. A 1 GeV proton beam was used to bombard two kinds of targets held at temperatures in the range of 1900–2100 °C. The first one was a target-ion source assembly slightly modified to withstand 3 months of continuous heating at a temperature of about 2050 °C. The second unit was of a new kind, where ionisation takes place in the target volume itself. A comparison of the on-line isotopic yields before and after heating for 3 months is here reported. The yields and release times of Rb, Cs and In are compared with the ones obtained from a standard reference target, as measured in previous experiments.

A series of on-line mass separation experiments have been performed at the IRIS facility to measure the yield and release of Rb and Cs neutron-rich isotopes produced by fission reaction of 238U. A 1 GeV proton beam was used to bombard uranium carbide targets with the densities of 11 g/cm3 and 1.5 g/cm3 held at temperatures in the range (2000-2230) °C. The release curves of Rb and Cs long-lived isotopes were measured from both kinds of targets. The overall production efficiency was determined making use of experimentally measured cross-sections of that isotope production. Comparison of the experimental yields of Rb and Cs isotopes with the calculated ones after corrections for losses due to finite release times suggests that the diffusion is the dominating process reducing the efficiency for short-lived isotopes. When normalized to the same thickness, an enhancement for the high-density rod target of the measured isotope yields is observed when going far from stability. This is possibly explained by the reactions induced by secondary neutrons. A significant odd-even effect with higher yields of Cs even neutron isotopes has been observed, confirming a similar effect obtained in earlier experiments.

Production of radioactive ions has started at GANIL on the SPIRAL facility since 2001 and numerous multicharged radioactive ion beams have been delivered for high energy nuclear experiments. This article makes an overview of the different beams that have been produced. In the mean time, an important R and D research program is continued in oder to produce new species of radioactive elements. A new concept of multicharged radioactive production that couples a monocharged ion source, based on the monolithe concept, to an ecr ion source like nanogan3 is under developments and is described The development of monocharged ion sources with high efficiencies is also motivated by a new big project that is under studies at GANIL : the SPIRAL 2 Project. The goal of this project consists in extending the disponible radioactive ion beams to very heavy elements created with a new method of production : while the spiral 1 facility uses the projectile fragmentation for radioactive nuclei production, the spiral 2 project is based on the fission of a Uranium carbide target induced by a neutron flow created by a high intensity deuton beam. The principle and an overview of the project is presented.Production of radioactive ions has started at GANIL on the SPIRAL facility since 2001 and numerous multicharged radioactive ion beams have been delivered for high energy nuclear experiments. This article makes an overview of the different beams that have been produced. In the mean time, an important R and D research program is continued in oder to produce new species of radioactive elements. A new concept of multicharged radioactive production that couples a monocharged ion source, based on the monolithe concept, to an ecr ion source like nanogan3 is under developments and is described The development of monocharged ion sources with high efficiencies is also motivated by a new big project that is under studies at GANIL : the SPIRAL 2 Project. The goal of this project consists in extending the disponible radioactive ion beams to very heavy elements created with a new method of production : while the spiral 1 facility uses the projectile fragmentation for radioactive nuclei production, the spiral 2 project ...

The conventional methods for measuring the polarization of electron beams are either time consuming, invasive or accurate only to a few percent. We developped a method to measure electron beam polarization by observing the light emitted by argon atoms following their excitation by the impact of polarized electrons. The degree of circular polarization of the emitted fluorescence is directly related to the electron polarization. We tested the polarimeter on a test GaAs source available at the MAMI electron accelerator in Mainz, Germany. The polarimeter determines the polarization of a 50 keV electron beam decelerated to a few eV and interacting with an effusive argon gas jet. The resulting decay of the excited states produces the emission of a circularly polarized radiation line at 811.5 nm which is observed and analyzed.

High-spin states of $^{84}$Se, produced as a fission fragment in the fusion-fission reaction $^{18}$O+$^{208}$Pb and studied with the EUROBALL IV array, have been identified for the first time. Their interpretation gives new insights about the evolution of the N=50 shell gap at the vicinity of $^{78}$Ni. To characterize this evolution, it would be worth using a new device devoted to the high-spin studies of neutron-rich nuclei produced by asymetric fission modes. Such dedicated studies are reported in a second part.

Radioactive ion beam intensities have been measured at ISOL (isotope separation on-line) facilities from many different targets, but only rarely these intensities are converted into production cross-sections. Here we discuss the method and possible problems in this conversion at the examples of Kr and Xe produced by 1.4 GeV-proton-induced fission of 238U at ISOLDE and Rb and Cs produced by approx. 10 MeV-neutron-induced fission of 238U at PARRNe.

A source of neutron rich ions can be conceived through the photo-fission process. An exploratory study of such a source is realized. A survey of the radiative electron energy loss theory is reported in order to estimate numerically the bremsstrahlung production of thick targets. The resulted bremsstrahlung angular and energy theoretical distributions delivered from W and UCx thick converters are presented and compared with previous results. Some quantities as the number of fission events produced in the fissionable source and the energy loss in the converters are also reported as function of the geometry of the combination and the incident electron energy. An attempt of comparison with experimental data shows a quantitative agreement. This study is focussed on initial kinetic energies of the electron beam included in the range 30–60 MeV, suitable for the production of large radiative γ-ray yields able to induce the 238 U fission through the giant dipole resonance. A confrontation with the number of fission events produced in the frame of the fast neutron induced fission method indicates that the photo-fission can be a competitive concept.

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.

Yields of neutron-rich isotopes produced by fast neutron induced fission of 238 U were measured at the ISOL set-up Production dAtomes Radioactifs Riches en Neutrons. A surface ion source was used to ionize selectively elements with low ionization potentials. In order to observe also the most n-rich isotopes, the identification was achieved by a combined measurement of b- and c-rays and b-delayed neutrons. The flux of fast neutrons inducing fission was generated by a 1 lA beam of 26 MeV deuterons stopped in a graphite converter. The target was a standard ISOLDE type 238 UC