%0 Generic
%A Grussie, Florian
%C Heidelberg
%D 2016
%F heidok:21435
%R 10.11588/heidok.00021435
%T Experimental sudies of ion-neutral reactions under astrophysical conditions
%U https://archiv.ub.uni-heidelberg.de/volltextserver/21435/
%X Ion-neutral collisions are pivotal for the gas-phase synthesis of complex molecules in the  interstellar medium. Accurate modeling of the astrochemical network relies on precise  laboratory data of reaction rate coefficients and their branching ratios. For the majority  of ion-neutral reactions, rate coefficients at astrophysical conditions are completely  unknown. To gain an experimental insight of ion-neutral, gas-phase chemistry under  interstellar conditions, two different experimental approaches are presented. One of  the most fundamental ions for interstellar chemistry is H3+. This ion is assumed to  be thermalized in collisions with H2. However, recent astronomical observations of H2  and H3+ in diffuse interstellar clouds revealed a significant difference in their excitation  temperatures. In this work, 22 pole trap measurements, performed at the Max  Planck Institute for Nuclear Physics (MPIK) in Heidelberg, of the H3+ + H2 reaction at  thermal equilibrium are presented and discussed. For future experiments on ion-atom  reactions, an injection beamline for the Cyrogenic Storage Ring (CSR) was developed  to perform merged-beams experiments on neutral ground-state atoms superimposed  with the cooled, stored ions in the CSR.