Search results for "Storage ring"
showing 10 items of 157 documents
Low-temperature X-ray detectors for precise Lamb shift measurements on hydrogen-like heavy ions
2000
The precise determination of the Lamb shift in heavy hydrogen-like ions provides a sensitive test of quantum electrodynamics in very strong Coulomb"elds, not accessible otherwise. For the investigation of the Lyman-a transitions in 208Pb81‘ or 238U91‘ with su$cient accuracy a high resolving calorimetric detector for hard X-rays (E)100 keV) is presently developed. The detector modules consist of arrays of silicon thermistors and of X-ray absorbers made of high Z material to optimize the absorption e$ciency. The detectors are housed in a specially designed 3He/4He dilution refrigerator with a side arm which "ts to the geometry of the internal target of the storage ring ESR at GSI Darmstadt. T…
Ion beam production and study of radioactive isotopes with the laser ion source at ISOLDE
2017
At ISOLDE the majority of radioactive ion beams are produced using the resonance ionization laser ion source (RILIS). This ion source is based on resonant excitation of atomic transitions by wavelength tunable laser radiation. Since its installation at the ISOLDE facility in 1994, the RILIS laser setup has been developed into a versatile remotely operated laser system comprising state-of–the-art solid state and dye lasers capable of generating multiple high quality laser beams at any wavelength in the range of 210–950 nm. A continuous programme of atomic ionization scheme development at CERN and at other laboratories has gradually increased the number of RILIS-ionized elements. At present, …
Schottky mass measurements of stored and cooled neutron-deficient projectile fragments in the element range of 57≤Z≤84
2000
Abstract A novel method for direct, high precision mass measurements of relativistic exotic nuclei has been successfully applied in the storage ring ESR at GSI. The nuclei of interest were produced by projectile fragmentation of 930 MeV / u bismuth ions, separated in-flight by the fragment separator FRS, stored and cooled in the ESR. The mass values have been deduced from the revolution frequencies of the coasting cooled ions. We have measured 104 new mass values with a precision of about 100 keV and a resolving power of 3.5×10 5 for the neutron-deficient isotopes of the elements 57≤Z≤84 . This paper presents the experimental method, the mass evaluation and a table of the experimental mass …
Direct Ionization Impact on Accelerator Mixed-Field Soft-Error Rate
2020
We investigate, through measurements and simulations, the possible direct ionization impact on the accelerator soft-error rate (SER), not considered in standard qualification approaches. Results show that, for a broad variety of state-of-the-art commercial components considered in the 65-16-nm technological range, indirect ionization is still expected to dominate the overall SER in the accelerator mixed-field. However, the derived critical charges of the most sensitive parts, corresponding to ~0.7 fC, are expected to be at the limit of rapid direct ionization dominance and soft-error increase.
Bunching and cooling of radioactive ions with REXTRAP
2002
The properties of radioactive ion beams produced by the present on-line target ion source technology are often not suitable for direct post acceleration. For that purpose pulsed and cooled beams of higher charged ions are required. In the case of REX-ISOLDE, the post accelerator at the CERN-ISOLDE radioactive beam facility, a unique system for beam preparation is used. It consists of a gas-filled cylindrical Penning trap (REXTRAP) for bunching and cooling followed by an electron beam ion source for charge state breeding. The Penning trap has been successfully operated with an efficiency of up to 40% and a total number of up to 107 ions stored. Buffer-gas sideband cooling at the ions’ cyclot…
First isochronous mass spectrometry at the experimental storage ring ESR
2000
Short-lived exotic nuclei can be produced and separated with the high-energy secondary nuclear beam facility FRS at GSI. These nuclides can be injected and stored in the storage ring ESR. The lower lifetime limit of the presently existing methods for mass measurements on these nuclides at the ESR is about a few seconds. We have developed and investigated an isochronous operational mode of the ESR, that makes mass measurements of nuclides with lifetimes down to a few ls feasible. It has been commissioned in experiments using long-lived nuclides with known masses. A mass resolving power of about 150 000 has been achieved in a "rst pilot experiment. A suitable detector system has been implemen…
Transverse laser cooling of a radio-frequency bunched ion beam in the storage ring TSR
1996
Abstract We report on the observation of the indirect transverse laser cooling effect in a radio-frequency bunched beam of 7.3 MeV 9 Be + ions, stored in the Heidelberg Test Storage Ring and subject to direct longitudinal laser cooling. This bunched scheme offers particular advantages for producing ultracold beams with unprecedented phase-space densities.
Observation of a dramatic hindrance of the nuclear decay of isomeric states for fully ionized atoms
2003
Abstract The half-lives of isomeric states of fully ionized 144Tb, 149Dy and 151Er have been measured. These nuclides were produced via fragmentation of about 900 MeV/u 209Bi projectiles, separated in flight with the fragment separator (FRS) and stored in the cooler ring (ESR). The decay times of the cooled fragments have been measured with time-resolved Schottky spectrometry. We observed for the first time drastic increases of the half-lives of bare isomers by factors of up to 30 compared to their neutral counterparts. This is due to the exclusion of the strong internal conversion and electron-capture channels in the radioactive decay of these bare nuclei. The experimental results are in g…
The Super-FRS Project at GSI
2002
The GSI projectile fragment separator FRS has demonstrated with many pioneering experiments the research potential of in-flight separators at relativistic energies. Although the present facility has contributed much to the progress in the field of nuclear structure physics, major improvements are desirable in the future. The characteristics of the proposed next-generation facility at GSI, the Super-FRS, will be presented and compared to other projects. The Super-FRS is a large-acceptance superconducting fragment separator followed by different experimental branches including a combination with a new storage-cooler ring system. This system consists of a collector ring (CR) and a new experime…
Neutrino oscillation physics with a higher-γ β-beam
2004
The precision measurement and discovery potential of a neutrino factory based on boosted radioactive ions in a storage ring (“β-beam”) is re-examined. In contrast with past designs, which assume ion γ factors of ∼100 and baselines of L=130 km, we emphasize the advantages of boosting the ions to higher γ and increasing the baseline proportionally. In particular, we consider a “medium-γ” scenario (γ∼500, L∼730 km) and a “high-γ” scenario (γ∼2000, L∼3000 km). The increase in statistics, which grow linearly with the average beam energy, the ability to exploit the energy dependence of the signal and the sizable matter effects at this longer baseline all increase the discovery potential of such a…