Status report on the GANIL facility

http://accelconf.web.cern.ch/AccelConf/c84/papers/a02.pdfInternational audienc

Influence of Neutron Enrichment on Disintegration Modes of Compound Nuclei

Cross sections, kinetic energy and angular distributions of fragments with charge 6$\le$Z$\le$28 emitted in 78,82Kr+40C at 5.5 MeV/A reactions were measured at the GANIL facility using the INDRA apparatus. This experiment aims to investigate the influence of the neutron enrichment on the decay mechanism of excited nuclei. Data are discussed in comparison with predictions of transition state and Hauser-Feshbach models.Comment: 8 pages, 1 figure, paper presented at the First Workshop on "State of the Art in Nuclear Cluster Physics" 13-16 May, 2008, at Strasbourg, France (SOTANCP2008) and accepted for publication at International Journal of Modern Physics E (Special Issue), Proceedings of SOTANCP2008 (to be published

GANIL Status report

The GANIL-Spiral facility (Caen, France) is dedicated to the acceleration of heavy ion beams for nuclear physics, atomic physics, radiobiology and material irradiation. The production of radioactive ion beams for nuclear physics studies represents the main part of the activity. The facility possesses a versatile combination of equipments, which permits to produce accelerated radioactive ion beams with two complementary methods: Isotope Separation In Line (ISOL) and In-Flight Separation techniques (IFS). Considering the future of GANIL, SPIRAL II projects aims to produce high intensity secondary beams, by fission induced with a 5 mA deuteron beam on an uranium target.Comment: 5 pages, 5 figures, to be appear in the proceedings of the 17th International Conference on Cyclotrons and their Application

Magnetic Moment of the Fragmentation Aligned 61Fe(9/2)+ Isomer

We report on the g factor measurement of the isomer in $^{61}Fe$ ($E^{*}=861 keV$). The isomer was produced and spin-aligned via a projectile-fragmentation reaction at intermediate energy, the Time Dependent Perturbed Angular Distribution (TDPAD) method being used for the measurement of the g factor. For the first time, due to significant improvements of the experimental technique, an appreciable residual alignment of the isomer has been observed, allowing a precise determination of its g factor: $g=-0.229(2)$. Comparison of the experimental g factor with shell-model and mean field calculations confirms the $9/2^+$ spin and parity assignments and suggests the onset of deformation due to the intrusion of Nilsson orbitals emerging from the $\nu g_{9/2}$.Comment: 4 figures. Submitted to Phys. Rev. Let

Nuclear break-up of 11Be

The break-up of 11Be was studied at 41AMeV using a secondary beam of 11Be from the GANIL facility on a 48Ti target by measuring correlations between the 10Be core, the emitted neutrons and gamma rays. The nuclear break-up leading to the emission of a neutron at large angle in the laboratory frame is identified with the towing mode through its characteristic n-fragment correlation. The experimental spectra are compared with a model where the time dependent Schrodinger equation (TDSE) is solved for the neutron initially in the 11 Be. A good agreement is found between experiment and theory for the shapes of neutron experimental energies and angular distributions. The spectroscopic factor of the 2s orbital is tentatively extracted to be 0.46+-0.15. The neutron emission from the 1p and 1d orbitals is also studied

Transport and cooling of singly-charged noble gas ion beams

The transport and cooling of noble gas singly-charged ion beams by means of a Radio Frequency Quadrupole Cooler Buncher (RFQCB) have been studied at the LIMBE low energy beam line of the GANIL facility. Ions as light as $^{4}He^+$ have been cooled and stored before their extraction in bunches using $H_2$ as buffer gas. Bunches characteristics have been studied as a function of the parameters of the device. Sizeable transmissions of up to 10 $$ have been obtained. A detailed study of the lifetime of ions inside the buncher has been performed giving an estimate of the charge exchange cross-section. Results of a microscopic Monte-Carlo transport code show reasonable agreement with experimental data.Comment: 13 figure

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International audienceThe GANIL facility consists of three successive cyclotrons. The tuning of these cyclotrons and of the transfer beam lines isachieved in about 24 hours. Reducing this setting time would enable to increase the time allocated to physics experiments.New tools are realized for automatic beam tuning. These tools are expected to make the tuning easier, shorter and morereproducible

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International audienceThe GANIL facility consists of three successive cyclotrons. The tuning of these cyclotrons and of the transfer beam lines isachieved in about 24 hours. Reducing this setting time would enable to increase the time allocated to physics experiments.New tools are realized for automatic beam tuning. These tools are expected to make the tuning easier, shorter and morereproducible

Study of intermediate velocity products in the Ar+Ni collisions between 52 and 95 A.MeV

Intermediate velocity products in Ar+Ni collisions from 52 to 95 A.MeV are studied in an experiment performed at the GANIL facility with the 4$\pi$ multidetector INDRA. It is shown that these emissions cannot be explained by statistical decays of the quasi-projectile and the quasi-target in complete equilibrium. Three methods are used to isolate and characterize intermediate velocity products. The total mass of these products increases with the violence of the collision and reaches a large fraction of the system mass in mid-central collisions. This mass is found independent of the incident energy, but strongly dependent on the geometry of the collision. Finally it is shown that the kinematical characteristics of intermediate velocity products are weakly dependent on the experimental impact parameter, but strongly dependent on the incident energy. The observed trends are consistent with a participant-spectator like scenario or with neck emissions and/or break-up.Comment: 37 pages, 13 figure

Survey and alignment concept for the SPIRAL2 accelerator (status report)

International audienceThe SPIRAL2 project located at the GANIL facility (Caen, France) has been studied since the beginning of 2003, and is now under construction. This project aims at delivering rare (radioactive) isotope beams with intensities not yet available with presently running machines. An important aspect of this project is that it is foreseen to deliver up to five different beams in parallel to the users. This paper is a status report on the survey and alignment techniques selected for installation of the SPIRAL2 accelerator device