Research with CRYRING@ESR

In order to enable laser spectroscopy experiments at CRYRING, a new general purpose fluorescence detector is being developed at the University of Münster. The design allows detection from ultraviolet wavelengths to the near infrared regime. Thus, the detector can be used to observe a large variety of atomic transitions. Among others Mg- (at 280 nm) and Ca+ (at 854 nm/866 nm) ions have...

In an electron-ion crossed-beams experiment, the experimental sensitivity is mainly determined by the densities of both beams in the interaction region. Aiming at the extension of the available range of accessible electron energies and densities, a new high-power electron gun has been developed and built. It delivers a ribbon-shaped beam with high currents at all energies variable between 10...

Dielectronic-recombination (DR) spectra of highly-charged W${}^{𝑞+}$ and Ir${}^{𝑞+}$ ions have been measured by employing the Electron-Beam Ion Trap (EBIT) at National Institute of standards and Technology [1] and the Main Magnetic Focus Ion Trap (MaMFIT) [2] at Justus-Liebig Universität Gießen, respectively, over wide ranges of electron-beam energies. A series of DR resonances involving...

The heavy-ion storage ring CRYRING at GSI/FAIR is particularly suited to investigate the collision dynamics for very highly charged ions in the highly adiabatic and non-perturbative regime where the ratio of projectile charge state to projectile velocity qproj/vproj>>1. We will discuss electron/lepton spectroscopy for studying leptons as authentic and precise messengers from extreme fields in...

The radiative recombination (RR) is a one of the most important processes occurring in the interaction of highly charged ions with electrons. During the last decades the RR was actively studied in various aspects related to atomic and plasma physics, astrophysics, and accelerator physics. Recently, the RR of U92+ ions with electrons was studied in a subshell-selective manner by observing the...

The structure of the few electrons heavy ions and the dynamics of the collisions of the ion with atoms can be precisely investigated by measurement of the radiation spectrum emitted in the electron-ion interaction. Detection of the radiation spectrum can be performed using conventional semiconductor detectors or high-resolution crystal spectrometers. However, as shown by the latest...

We present PEGASUS, a versatile and mobile spin-polarized electron target designed, constructed and build at GSI. It consists of a laser diode driven bulk GaAs photocathode, extraction energies up to 10 keV and an electrostatical cylindrical bender turning the polarization angle. First results characterizing the beam parameters will be shown, as well as proposed experiments, focussing on the...

High-precision X-ray spectroscopy of highly-charged heavy ions is one of the established subjects within the program of SPARC. At CRYRING, such experiments profit from the low ion velocity, which minimizes systematic errors from correction of the Doppler shift. One prominent example is the investigation of the 1s Lamb Shift of hydrogen-like heavy ions. As a benchmark for a detector with...

The low energy storage ring CRYRING is currently being comissioned as the first storage ring for FAIR phase 0 at GSI. CRYRING features an electron cooler to cool stored ions and thus achieve a low momentum spread of the beam. To determine the velocity of the ions a precise knowledge of the electron cooler voltage is essential. In earlier measurements of hyperfine transitions in hydrogen- and...

With the FISIC project, we propose an experimental crossed-beam arrangement at SPIRAL2 facility to measure absolute cross-sections for fundamental atomic processes in the intermediate collision regime. In future, it is also planned to move the low-energy branch of the FISIC setup to CRYRING to perform experiments with heaviest ions. For the realization of such a challenging experimental...

The radionuclide Ti44 is one of the few cosmogenic nuclei that were directly observed by satellite based gamma-ray observatories. It is produced in core collapse supernovae by the reaction Ca40(a,g)Ti44. The main reaction consuming Ti44 is Ti44(a,p)V47. The precise knowledge of both reaction rates is therefore crucial for the determination of the final amount of Ti44 produced in the supernova....

The collision of highly charged, heavy ions with atomic or molecular gas targets or free electrons causes a variety of reactions such as electronic excitation, ionization, radiative electron capture and, in the case of molecules, dissociation. These processes have an important role in Astrophysics, with solar wind as a source for highly charged ions that interact with cometary or atmospheric...