We describe a versatile experimental apparatus designed for investigating ion-molecule reaction dynamics at low temperatures under ultra-high vacuum conditions (<8 × 10-11 Torr). The system integrates laser-cooled atomic ions confined in a linear Paul trap with a pulsed molecular beam featuring simultaneous quantum-state and velocity selection. Reaction products are identified using fluorescence imaging and a time-of-flight mass spectrometer. The setup accommodates a broad range of ionic and neutral species-including Be+, C+, H2, N2, O2, H2O, and others-enabling high-sensitivity studies of reaction dynamics. As a benchmark, we present measurements of the Be+ + H2 reaction across a range of collision energies, including reactions with H2 vibrationally excited to the v = 1 level. The apparatus offers fine control over both internal and external degrees of freedom, providing a general platform for cold ion-molecule reaction studies.
We propose a method for controlling a class of low temperature chemical reactions. Specifically, we show the hydrogen abstraction channel in the reaction of formaldehyde
(H2CO) and the hydroxyl radical
(OH) can be controlled through either the molecular state or an external electric field. We also outline experiments for investigating and demonstrating control over this important reaction. To this end, we report the first Stark deceleration of
H2CO. We have decelerated a molecular beam of
H2CO essentially to rest, producing molecules at
100mK with a density of $\ensuremath{\sim}{10}^{6}\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}3}$.
A new experiment is being built at the Max-Planck-Institut für Kernphysik (MPIK) within the PRIOC project (Precision studies on Ion Collisions) where a reaction microscope (Remi) and a magneto-optical trap (MOT) as target are combined to a so called MOTRemi. This setup will be implemented into the ion storage ring 'Testspeicherring' (TSR) of the MPIK. The world-wide unique combination of these three state-of-the-art technologies shall enable to perform kinematically complete studies of ion-atom collision with unprecedented detail and resolution. In this thesis, a two-dimensional magneto-optical trap (2D-MOT) was developed and tested as a source of slow lithium atoms for the loading of the target MOT. This method allows a very compact setup and oers a collimated beam and a ux of cold atoms comparable to the highest uxes achieved by using laser cooling. The temperature of the atomic beam was determined to be at the scale of a few Kelvin and, thus, it is already an adequate stand-alone target for momentum resolved experiments.