Laser ablation inductively coupled plasma mass spectrometry was used for spatially resolved trace element analysis of archaeological samples. An autofocus system was built in order to achieve reproducible ablation conditions. This system allows focusing of any sample automatically, with an accuracy of 10–50 μm, in the focal plane of the laser, or any height specified by the user, and can correct for surface roughness point per point. The applicability of the autofocus system is demonstrated. Trace element determination of archaeological samples with a lateral resolution of 50 μm is shown as an example. Absolute detection limits of 01–1.4 pg are achieved.

We present a simple and efficient method for the broadband laser excitation of ions in a fast beam by optical rapid adiabatic passage. The method relies on the frequency chirp affecting the ions in continuous-wave fixed-frequency laser light as a result of the Doppler effect when they are accelerated in local electrostatic fields. We have studied this excitation scheme at the Heidelberg Test Storage Ring and demonstrated its particular application to overcome collisional losses in laser cooling of fast stored ion beams.

Three-dimensional laser cooling of a fast stored ion beam has been demonstrated at the Heidelberg Test Storage Ring. With a purely longitudinal cooling force-applied to a 7.3 MeV Be-3(+) beam, we have observed an efficient transverse cooling effect. We interpret this observation as being due to a thermal intrabeam relaxation between the different degrees of freedom that is caused by Coulomb collisions of the stored particles.

The role of modifiers in electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) for the determination of refractory elements such as La or U and carbide forming elements such as B has been studied. Solutions of NH4F, NH4Cl, NH4Br, NaCl, NaF, NH4HSO4, (NH4)(2)HPO4, the gaseous halogenated hydrocarbons CHF3 and CCl2F2 and HCl have been used as modifiers.The mechanism of the modifier effect and the influence of modifiers on sensitivity enhancement have been investigated. The sensitivity enhancements are great enough to achieve absolute detection limits of 2-6 pg for boron and 10 fg for La and U. The signal reproducibility is 0.5-3.0% for a concentration of 1 mu g 1(-1) La and U, and 20 mu g 1(-1) boron. Therefore, by adding modifiers, the use of ETV-ICP-MS can be extended to trace element determination of refractory and carbide forming elements in mu l amounts of sample.

Laser cooling of {sup 24}Mg{sup +} has now begun at the ASTRID storage ring. In contrast to {sup 7}Li{sup +}, which has been used up to now, it is now possible for the laser to interact with all of the beam. In this paper some of the results from the first beam time with {sup 24}Mg{sup +} are described. By frequency chirping a single laser, laser cooling has been performed on a coasting beam, and first evidence of sympathetic transverse cooling has been observed.

Since the first observation of laser cooling of fast, stored ions,1 quantitative investigations of the cooling process and its limits have been undertaken. To overcome the limited interaction time when cooling ions at velocities of approximately 5% of the velocity of light, the ions are trapped in the Heidelberg test storage ring (TSR). There, they can interact repeatedly with a copropagating laser beam in one of the four straight sections of the TSR.

At the TSR cooler ring at Heidelberg, laser studies were carried out using singly charged lithium and beryllium ions. Laser spectroscopy of relativistic lithium ions (v=0.04c) yielded signals with a narrow linewidth, suitable for an experimental test of special relativity. A dramatic reduction of the beam temperature, as defined by the longitudinal velocity spread, was achieved via laser cooling in both cases. At the ion energies available at ESR it will become possible to prepare and store bare ions up to U92+. Electron cooling was succesfully demonstrated for hydrogen-like Bi82+ ions, where a laser experiment is scheduled to study the ground-state hyperfine splitting.

Laser cooling of ions at relativistic energies was first observed at the TSR storage ring in Heidelberg. A 7Li+ ion beam moving at 6.4% the speed of light was overlapped with resonant co‐ and counter‐propagating laser beams. The longitudinal temperatures were found to pass below 190 mK. Limits and applications of laser cooled relativistic ion beams are discussed. Laser cooling and electron cooling of the ion beam were combined.

Experiments with relativistic ions at the test storage ring TSR [P. Baumann et al., Nucl. Instr. and Meth. A268 (1988) 531] demonstrate the potential of the interaction of laser light with energetic stored ions for spectroscopic purposes as well as for manipulation of the ion velocity. Latest results for Li+ ions are reported. At the ion energies available at ESR [B. Franzke, Nucl. Instr. and Meth. B24B25 (1987) 19] it will become possible to prepare and store bare ions up to U92+. Experiments using these exotic beams are discussed and an outlook to the situation at even higher energies is given.

The first successful laser cooling of ions at relativistic energies was observed at the Heidelberg TSR storage ring. A $^{7}\mathrm{Li}^{+}$-ion beam of 13.3 MeV was oberlapped with resonant copropagating and counterpropagating laser beams. The metastable ions were cooled from 260 K to a longitudinal temperature of below 3 K and decelerated by several keV. The longitudinal velocity distribution was determined by a fluorescence method. After laser cooling a strongly enhanced narrow peak appeared in the Schottky noise spectrum in addition to the uncooled ion distribution.