Search results for "Dye"
showing 10 items of 577 documents
Performance of a high repetition pulse rate laser system for in-gas-jet laser ionization studies with the Leuven laser ion source @ LISOL
2012
The Leuven Isotope Separator On-Line (LISOL) facility at the Cyclotron Research Center (CRC) Louvain-la-Neuve; The laser ionization efficiency of the Leuven gas cell-based laser ion source was investigated under on- and off-line conditions using two distinctly different laser setups: a low-repetition rate dye laser system and a high-repetition rate Ti:sapphire laser system. A systematic study of the ion signal dependence on repetition rate and laser pulse energy was performed in off-line tests using stable cobalt and copper isotopes. These studies also included in-gas-jet laser spectroscopy measurements on the hyperfine structure of 63Cu. A final run under on-line conditions in which the ra…
First observation of a resonance ionization signal on242mAm fission isomers
1992
The feasibility of a hyperfine spectroscopy on242mAm fission isomers has been demonstrated at the low target production rate of 10/s. The experimental method employed is based on resonance ionization spectroscopy in a buffer gas cell with detection of the ionization process by means of the fission decay of the isomers. The resonance ionization has been performed in two steps, utilizing an excimer dye laser combination with a repetition rate of 300 Hz. The first resonant step proceeds through theJ=7/2 term at 21440.35 cm−1, which has been excited with the tuncable dye laser beam of a wavelength of 466.28 nm, the second non-resonant step is achieved with the 351 nm radiation of the excimer la…
Radiation detected resonance ionization spectroscopy on208Tl and242fAm
1993
An ultra-sensitive laser spectroscopic method has been developed for the hyperfine spectroscopy of short-lived isotopes far off stability produced by heavy ion induced nuclear reactions at very weak intensity (> 1/s). It is based on resonance ionization spectroscopy in a buffer gas cell with radiation detection of the ionization process (RADRIS). As a first on-line application of RADRIS optical spectroscopy at242fAm fission isomers is in progress at the low target production rate of 10/s. The resonance ionization has been performed in two steps utilizing an excimer dye laser combination with a repetition rate of 300 Hz. The first resonant step proceeds through terms which correspond to wave…
Production of radioactive Ag ion beams with a chemically selective laser ion source
1997
Abstract We have developed a chemically selective laser ion source at the CERN-ISOLDE facility in order to study neutron-rich Ag nuclides. A pulsed laser system with high repetition rate has been used based on high-power coppe-vapour pump lasers and dye lasers. With this source significant reductions of the isobaric background has been achieved.
Laser systems for on-line laser ion sources
2008
Since its initiation in the middle of the 1980s, the resonant ionization laser ion source has been established as a reliable and efficient on-line ion source for radioactive ion beams. In comparison to other on-line ion sources it comprises the advantages of high versatility for the elements to be ionized and of high selectivity and purity for the ion beam generated by resonant laser radiation. Dye laser systems have been the predominant and pioneering working horses for laser ion source applications up to recently, but the development of all-solid-state titanium:sapphire laser systems has nowadays initiated a significant evolution within this field. In this paper an overview of the ongoing…
Isomer separation of Cu and Cu with a resonance ionization laser ion source
2000
Abstract Radioactive copper isotopes were ionized with the resonance ionization laser ion source (RILIS) at the on-line isotope separator ISOLDE (CERN). Using the different hyperfine structure in the 3d10 4s 2 S1/2 – 3d10 4p 2 P01/2 transition the low- and high-spin isomers of 70 Cu were selectively enhanced by tuning the laser wavelength. The light was provided by a narrow-bandwidth dye laser pumped by copper vapor lasers (CVL) and frequency doubled in a BBO crystal. The ground state to isomeric state intensity ratio could be varied by a factor of 30, allowing to assign gamma transitions unambiguously to the decay of the individual isomers. It is shown that the method can also be used to…
Laser preparation of bunched ion beams
1997
Abstract Laser ionization at ISOLDE is performed with high repetition laser beams in the ion source unit and for daughter elements with low repetition lasers synchronized with laser desorption from a secondary target. We are preparing an implementation of thermal adsorption followed by laser desorption and laser ionization in the target ion source unit of ISOLDE. The combination of resonance ionization with thermal bunching allows the preparation of bunched and chemically pure ion beams. Bunched ion beams of Mg or Ca are prepared for post-acceleration at REX-ISOLDE. In order to investigate the process of adsorption and pulsed laser desorption, experiments are performed with Ba vapour. In a …
Site-selective luminescence study of defects. in gamma-irradiated glassy germanium dioxide
1996
Abstract Luminescence of γ-irradiated samples of GeO2 glass was studied using dye laser excitation in the wavelength region between 590 and 656 nm. An inhomogeneously broadened luminescence band with a peak around 1.86 eV, halfwidth of 0.16 eV and decay constant τ ≈ 5.1 μs was found. At temperatures below 20 K a resonance ZPL and a vibronic peak 710 cm−1 below the laser photon energy emerge when laser is tuned to energies between 1.95–1.89 eV. The site-selective luminescence spectra are qualitatively similar to those of the non-bridging oxygen hole center (NBOHC) in SiO2 glass and are attributed to NBOHC in glassy GeO2. The measured ratio between the energies of the observed local vibration…
Data acquisition, remote control and equipment monitoring for ISOLDE RILIS
2013
Abstract With a steadily increasing on-line operation time up to a record 3000 h in the year 2012, the Resonance Ionization Laser Ion Source (RILIS) is one of the key components of the ISOLDE on-line isotope user facility at CERN. Ion beam production using the RILIS is essential for many experiments due to the unmatched combination of ionization efficiency and selectivity. To meet the reliability requirements the RILIS is currently operated in shift duty for continuous maintenance of crucial laser parameters such as wavelength, power, beam position and timing, as well as ensuring swift intervention in case of an equipment malfunction. A recent overhaul of the RILIS included the installation…
Performance of Dye and Ti:sapphire laser systems for laser ionization and spectroscopy studies at S3
2020
The novel and sensitive In-Gas Laser Ionization Spectroscopy (IGLIS) technique enables high-precision laser spectroscopy of the heaviest elements and isotopes very far from stability that are produced in fusion-evaporation reactions at in-flight separators. Powerful and dedicated laser systems are required in these facilities to realize in-gas jet laser spectroscopy with optimal spectral resolution and efficiency. The performance with respect to the requirements for IGLIS studies at the low energy front-end of the Super Separator Spectrometer (S3) at GANIL, France, of Dye and Ti:sapphire laser systems is investigated. In addition, a number of specific experimental cases on key isotopes of t…