Ion source developments for stable and radioactive ion beams at GANIL

Since now many years, the Ganil ion source team has in charge to develop ion sources with three main purposes. The first one concerns the radioactive ion production that implies high efficiency ion sources as the amount of created exotic atoms is very low (between 10 to 108 particle per second). The second one deals with high intensities of stable metallic ion beams for the injectors of the accelerator while the last one tries to increase the intensities of very high charge state ion beams for atomic physic. Concerning radioactive ion production, the recent results obtained, in collaboration with the ISN Grenoble group, with the 1+/n+ method drove us to develop a new concept of ecr ion source for monocharged ion production. The results of the first tests of this source will be given. This new idea for the construction of ecr ion source can be applied to multicharged ion production. Concerning the high charge state ion beam production, a new source called SUPERSHYPIE has been built that allow to increase by a factor 2 the length of the plasma of an ECR4M source. This new concept has just been started and has produced arround 50 nAe of Ar17+ . The first results of this new source will be presented. Concerning the developments of metallic ion beams, a separated poster will be presented at this workshop

Permanent magnets under irradiation and radiocative alkali ion beam development for SPIRAL1

International audienceUp to now, eighteen Target Ion Source Systems (TISSs) have been built and used for the production of radioactive ion beams on SPIRAL 1 facility, based on the Isotope- Separator-On-Line (ISOL) method. The TISSs are composed of thick carbon targets and of fully permanentmagnet Electron Cyclotron Resonance Ion Sources (ECRISs) of the Nanogan III type. After irradiation and a decay period of two years, the irradiated TISSs are dismounted and if their magnetic fields are still suitable, the ECRIS are used with a new target. Thereby thirty-two runs have been performed using new or renewed TISSs. , After irradiation, the measured magnetic field sometimes reveals magnet damage. Our experience is reported here. In the second section, we present the progress on the NanoNaKE setup, which aims to extend the radioactive ion beams in SPIRAL 1 to the alkali elements, by connecting a surface-ionization source to the Nanogan III ECRIS via a compact 1+ ion beam line. The main issues and difficulties are discussed and the preliminary solutions are described

Nuclear charge radius of 8^8He

The root-mean-square (rms) nuclear charge radius of ^8He, the most neutron-rich of all particle-stable nuclei, has been determined for the first time to be 1.93(3) fm. In addition, the rms charge radius of ^6He was measured to be 2.068(11) fm, in excellent agreement with a previous result. The significant reduction in charge radius from ^6He to ^8He is an indication of the change in the correlations of the excess neutrons and is consistent with the ^8He neutron halo structure. The experiment was based on laser spectroscopy of individual helium atoms cooled and confined in a magneto-optical trap. Charge radii were extracted from the measured isotope shifts with the help of precision atomic theory calculations

SPIRAL II Project (electron option) - Preliminary Design Study

This document presents a Preliminary Design Study (PDS) of the electron option of the SPIRAL II project

Is there a dark decay of neutrons in 6^6He ?

Motivated by the four standard deviations discrepancy between the mean values for the neutron lifetime obtained from beam and bottle experiments, we have searched for a hypothetical neutron dark decay in $^6$He nuclei through the channel $^6{\rm He} \rightarrow ^4{\rm He}+n+\chi$. The experiment used a 25~keV high intensity $^6$He$^+$ beam with a high efficiency neutron detector. The search for a signal correlated with the $^6$He activity in the neutron detection rate resulted in a branching ratio ${\rm Br}_\chi \leq 4.0\times10^{-10}$ with a 95\% C.L. over the mass window $937.993 < m_\chi < m_n-0.975$ MeV. This result is five orders of magnitude smaller than required to solve the neutron lifetime discrepancy

Systematic comparison of ISOLDE-SC yields with calculated in-target production rates

Recently, a series of dedicated inverse-kinematics experiments performed at GSI, Darmstadt, has brought an important progress in our understanding of proton and heavy-ion induced reactions at relativistic energies. The nuclear reaction code ABRABLA that has been developed and benchmarked against the results of these experiments has been used to calculate nuclide production cross sections at different energies and with different targets and beams. These calculations are used to estimate nuclide production rates by protons in thick targets, taking into account the energy loss and the attenuation of the proton beam in the target, as well as the low-energy fission induced by the secondary neutrons. The results are compared to the yields of isotopes of various elements obtained from different targets at CERN-ISOLDE with 600 MeV protons, and the overall extraction efficiencies are deduced. The dependence of these extraction efficiencies on the nuclide half-life is found to follow a simple pattern in many different cases. A simple function is proposed to parameterize this behavior in a way that quantifies the essential properties of the extraction efficiency for the element and the target - ion-source system in question.Comment: 46 pages, 49 figures, background information on http://www-w2k.gsi.de/charms

Precision Measurement of the First Ionization Potential of Nobelium

One of the most important atomic properties governing an element’s chemical behavior is the energy required to remove its least-bound electron, referred to as the first ionization potential. For the heaviest elements, this fundamental quantity is strongly influenced by relativistic effects which lead to unique chemical properties. Laser spectroscopy on an atom-at-a-time scale was developed and applied to probe the optical spectrum of neutral nobelium near the ionization threshold. The first ionization potential of nobelium is determined here with a very high precision from the convergence of measured Rydberg series to be 6.626   21 ± 0.000   05     eV . This work provides a stringent benchmark for state-of-the-art many-body atomic modeling that considers relativistic and quantum electrodynamic effects and paves the way for high-precision measurements of atomic properties of elements only available from heavy-ion accelerator facilities

Identification of patients at risk for early death after conventional chemotherapy in solid tumours and lymphomas

1–5% of cancer patients treated with cytotoxic chemotherapy die within a month after the administration of chemotherapy. Risk factors for these early deaths (ED) are not well known. The purpose of this study was to establish a risk model for ED after chemotherapy applicable to all tumour types. The model was delineated in a series of 1051 cancer patients receiving a first course of chemotherapy in the Department of Medicine of the Centre Léon Bérard (CLB) in 1996 (CLB-1996 cohort), and then validated in a series of patients treated in the same department in 1997 (CLB-1997), in a prospective cohort of patients with aggressive non-Hodgkin's lymphoma (NHL) (CLB-NHL), and in a prospective cohort of patients with metastatic breast cancer (MBC series) receiving first-line chemotherapy. In the CLB-1996 series, 43 patients (4.1%) experienced early. In univariate analysis, age > 60, PS > 1, lymphocyte (ly) count ≤ 700 μl−1 immediately prior to chemotherapy (d1), d1-platelet count ≤ 150 Gl−1, and the type of chemotherapy were significantly correlated to the risk of early death (P ≤ 0.01). Using logistic regression, PS > 1 (hazard ratio 3.9 (95% Cl 2.0–7.5)) and d1-ly count ≤ 700 μl−1 (3.1 (95% Cl 1.6–5.8)) were identified as independent risk factors for ED. The calculated probability of ED was 20% (95% Cl 10–31) in patients with both risk factors, 6% (95% Cl 4–9) for patients with only 1 risk factor, and 1.7% (95% Cl 0.9–3) for patients with none of these 2 risk factors. In the CLB-97, CLB-NHL and MBC validation series, the observed incidences of early death in patients with both risk factors were 19%, 25% and 40% respectively and did not differ significantly from those calculated in the model. In conclusion, poor performance status and lymphopenia identify a subgroup of patients at high risk for early death after chemotherapy. © 2001 Cancer Research Campaignhttp://www.bjcancer.co

METALLIC ION DEVELOPMENTS AT GANIL

Radioactive ion beams (RIB) are routinely produced at GANIL by fragmentation of the projectile. A possible way to improve the RIB intensity is to increase the primary beam intensity impinging the target. Although high intensities can be obtained with an ECR ion source for gaseous elements, it is more difficult for metallic elements due to the poor ionization efficiency of the source. This report deals with metallic ion beam production at high intensity. Experimental results for Ca, Ni and Fe are presented. The oven and the MIVOC methods are compared

JPN Guidelines for the management of acute pancreatitis: severity assessment of acute pancreatitis

This article addresses the criteria for severity assessment and the severity scoring system of the Ministry of Health and Welfare of Japan; now the Japanese Ministry of Health, Labour, and Welfare (the JPN score). It also presents data comparing the JPN score with the Acute Physiology and Chronic Health Evaluation (APACHE) II score and the Ranson score, which are the major measuring scales used in the United States and Europe. The goal of investigating these scoring systems is the achievement of earlier diagnosis and more appropriate and successful treatment of severe or moderate acute pancreatitis, which has a high mortality rate. This article makes the following recommendations in terms of assessing the severity of acute pancreatitis