Extended areas of application of DESIREE by new instrumentation

The DESIREE double electrostatic ion-storage ring facility is world-unique in combining cryogenic operation with a double-ring structure allowing to pursue the scientific goal to study the properties of and reactions between positive and negative ions of atoms, molecules and clusters in well-defined quantum states.DESIREE is a Swedish National Infrastructure since January 2018.

In the current grant (2018-2024), a module for developments of DESIREE was excluded from funding, but we were encouraged to submit a separate research-infrastructure application for that purpose after demonstrating DESIREE´s capabilities.

A number of milestones for DESIREE have since been achieved, in particular the first results of mutual neutralization between ions stored in the two rings were published in 2020.The here sought expansion of the DESIREE research area through new instrumentation will widen the scope of experiments by introducing novel methods for ion-production, -cooling and -selection.

This includes improved ion-production methods such as formation of cold cluster ions inside helium nanodroplets, an additional electrospray ionization system, and an effective source for metal cluster cations.

A laser system is included for precision spectroscopy and manipulation of the quantum-state distribution of the stored ions for state-selective experiments.

For studies of complex ions, detection of charged fragments with a wide range of energy-to-charge ratios is essential and we propose such improvements by introducing new detectors and DESIREE operation schemes. Finally, we ask for funding to further improve the already excellent vacuum in DESIREE.

Further vacuum improvements are essential for the next generation of experiments.The national added value is to offer new experimental opportunities to Swedish researchers.

This will enable a broadening of the user base towards applications in e.g. atmospheric sciences, chemistry, biology and astrophysics.