Present status of the ALTO project

Submitted to AIP Conf. Proc., contribution to the Proceedings of the International Symposium on Exotic Nuclei EXON 2006 (Khanty-Mansiysk, Russia, 2006 July 17th-22nd) - Soumis à AIP conf. Proc.The Institute of Nuclear Physics of Orsay has built in the Tandem building an ISOL device based on photofission induced by a 50-MeV electron-beam~: ALTO (\textbf{A}ccélérateur \textbf{L}inéaire auprès du \textbf{T}andem d'\textbf{O}rsay). The project has been dimensioned to obtain $10^{11}$ fissions/s inside an UC$_x$ target. The objective of this facility is twofold~: ensure the development of the physics with beams at extraction-energy of fission products and to serve as a test bench for certain aspects of the R\&D for the SPIRAL2 project. The first electron beam has been extracted from the LINAC in december 2005 and a UC$_x$-target/ion-source ensemble has been irradiated for the first time in june 2006. The effective yields of the non-refractory fission fragments after extraction and mass separation have been measured during this experiment and are similar to the calculated predictions

Etude de l’effet de couche N=50 en direction de78Ni :contribution des études de radioactivité auprèsdu séparateur en ligne PARRNe

Pour aborder cette «autre chose», j’ai choisi de consacrer ce manuscrit aux recherchesqui m’ont le plus accaparé depuis l’obtention de ma («nouvelle») thèse en Décembre.2000 : la structure nucléaire des noyaux exotiques, parmi ceux-ci la région de la fermeturede couche N=50 non loin de 78Ni, et plus précisément par la technique de laséparation isotopique en ligne (ISOL) et les études de spectroscopie γ lors de la décroissanceradioactive des faisceaux arrêtés. C’est par cet exemple précis que j’ai tentéd’atteindre les critères définis par l’arrêté sus-cité. Ce mémoire est articulé autour despublications principales qui ont jalonné ces travaux, accompagnées de chapeaux destinésà les mettre au mieux en perspective en replaçant ces recherches dans un contexte plusgénéral (l’évolution des nombres magiques loin de la stabilité) et dans le paysage desautres travaux effectués soit auparavant soit simultanément sur d’autres installations depar le monde, avec d’autres techniques et pour accéder à d’autres observables

Raman spectroscopy, a non-destructive solution to the study of glass and its alteration

This paper presents the potential of Raman spectroscopy, a non-destructive technique which can be applied in-situ, for the analyses of glass and their alteration. Recent analytical developments are summarised for different glass composition and practical examples are given. The paper describes how to extract compositional information from the glass, first based on the spectra profile to distinguish rapidly alkali silicate from alkaline-earth alkali silicate and lead alkali silicate glass, then using the spectral decomposition and correlations to extract quantitative data. For alkali silicate glasses, that are most prone to alteration, the spectral characteristics are described to interpret the alteration process (selective leaching or dissolution of the glass) from the Raman spectra of the altered glass. These developments have greatly widened the potential of the technique and supplement well its ability to measure the thickness of the altered layer and identify the crystalline deposits

Low Energy States of 3181Ga50^{81}_{31} Ga_{50} : Elements on the Doubly-Magic Nature of 78^{78}Ni

Excited levels were attributed to $^{81}_{31}$Ga$_{50}$ for the first time which were fed in the $\beta$-decay of its mother nucleus $^{81}$Zn produced in the fission of $^{nat}$U using the ISOL technique. We show that the structure of this nucleus is consistent with that of the less exotic proton-deficient N=50 isotones within the assumption of strong proton Z=28 and neutron N=50 effective shell effects.Comment: 4 pages, REVTeX 4, 5 figures (eps format

Olive Mill Wastewater Valorization in Multifunctional Biopolymer Composites for Antibacterial Packaging Application

Olive mill wastewater (OMW) is the aqueous waste derived from the production of virgin olive oil. OMW typically contains a wide range of phenol-type molecules, which are natural antioxidants and/or antibacterials. In order to exploit the bioactive molecules and simultaneously decrease the environmental impact of such a food waste stream, OMW has been intercalated into the host structure of ZnAl layered double hydroxide (LDH) and employed as an integrative filler for the preparation of poly(butylene succinate) (PBS) composites by in situ polymerization. From the view point of the polymer continuous phase as well as from the side of the hybrid filler, an investigation was performed in terms of molecular and morphological characteristics by gel permeation chromatography (GPC) and X-ray diffraction (XRD); also, the thermal and mechanical properties were evaluated by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic thermomechanical analysis (DMTA). Antibacterial properties have been assessed against a Gram-positive and a Gram-negative bacterium, Staphylococcus aureus and Escherichia coli, respectively, as representatives of potential agents of foodborne illnesses

High-spin states with seniority v=4,4,6 in 119-126Sn

The 119-126Sn nuclei have been produced as fission fragments in two reactions induced by heavy ions: 12C+238U at 90 MeV bombarding energy, 18O+208Pb at 85 MeV. Their level schemes have been built from gamma rays detected using the Euroball array. High-spin states located above the long-lived isomeric states of the even- and odd-A 120-126Sn nuclei have been identified. Moreover isomeric states lying around 4.5 MeV have been established in 120,122,124,126Sn from the delayed coincidences between the fission fragment detector SAPhIR and the Euroball array. The states located above 3-MeV excitation energy are ascribed to several broken pairs of neutrons occupying the nu h11/2 orbit. The maximum value of angular momentum available in such a high-j shell, i.e. for mid-occupation and the breaking of the three neutron pairs, has been identified. This process is observed for the first time in spherical nuclei.Comment: 20 pages, 22 figures, 12 tables, accepted for publication in Physical Review

Study of the N=50 major shell effect close to 78^{78}Ni : First evidence of a weak coupling structure in 83_32^{83}\_{32}Ge_51\_{51} and three-proton configuration states in 81_31^{81}\_{31}Ga_50\_{50}

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, Japa

Particle-core coupling in S 37

R. Chapman et al. ; 8 págs.; 6 figs.; 2 tabs.Excited states of the neutron-rich N=21 S37 nucleus have been studied using binary grazing reactions produced by the interaction of a 215-MeV beam of S36 ions with a thin Pb208 target. The magnetic spectrometer, PRISMA, and the γ-ray array, CLARA, were used in the measurements. The level scheme of S37 was established to an excitation energy of 4196 keV and a number of new transitions were observed, in particular that corresponding to the decay of the proposed Jπ=(11/2-) level at an excitation energy of 2776 keV. The structure of the state is discussed within the context of state-of-the-art shell-model calculations using the SDPF-U effective interaction; the main component of the wave function corresponds to the coupling of the odd 1f7/2 neutron to the first 2+ state of the S36 core. The electromagnetic decay properties of the state are discussed within the context of a particle-core coupling model and the shell model. The other members of the multiplet of states are also discussed. ©2016 American Physical SocietyWe would like to thank the technical staff of the INFN Legnaro National Laboratory for their support during this experiment. This work was supported by the EPSRC (U.K). Four of us (A.H,M.B, K.L.K., and A.P.) would like to acknowledge the receipt of financial support from EPSRC during the course of this work. A.J. would like to acknowledge support from the Spanish Ministerio de Economía y Competitividad under Contract No. FPA2014-57196-C5-4-P. Z.D. acknowledges financial support from OTKA Grant No. K100835.Peer Reviewe

Search for Fingerprints of Tetrahedral Symmetry in 156Gd^{156}Gd

Theoretical predictions suggest the presence of tetrahedral symmetry as an explanation for the vanishing intra-band E2-transitions at the bottom of the odd-spin negative parity band in $^{156}Gd$. The present study reports on experiment performed to address this phenomenon. It allowed to determine the intra-band E2 transitions and branching ratios B(E2)/B(E1) of two of the negative-parity bands in $^{156}Gd$.Comment: presented by Q.T. Doan at XLII Zakopane School of Physics: Breaking Frontiers: Submicron Structures in Physics and Biology, May 2008. 5 pages, minor corrections. To be published in the proceeding