by
Henrik Cederqvist(Fysikum, Stockholms Universitet)
→
Europe/Stockholm
FA31
FA31
Description
DESIREE (Double ElectroStatic Ion Ring ExpEriment) is a new research
facility at Stockholm University and AlbaNova. Its main instrument consists
of two electrostatic ion storage rings with 8,6 meters circumferences and
with a common section for merged ion beams experiments. The two rings and
their vacuum chamber are cooled to 10 Kelvin by which most ions relax to
their lowest electronic and vibrational ground states during long time
storage. By this, it is possible to study collisions between internally cold
positive and negative ions at kinetic energies ranging down to the meV
range. DESIREE is the first instrument at which this is possible. The
commissioning work is well under way and 10 keV atomic and molecular ion
beams have been trapped and 1/e ion storage times of several minutes have
been measured. The physical pressure is in the 10^-14 mbar range at 13
Kelvin. The DESIREE rings are also well suited for studies of stabilities
and photo-absorption features of internally cold molecules. Experiments with
ion beams of atoms, molecules, clusters, and bio-molecules are possible.
First results using an Electro Spray Ion Source and ion beams of Polycyclic
Aromatic Hydrocarbons will be discussed briefly.