TY  - GEN
TI  - Study of the unimolecular decay of highly-excited anionic carbon dimers
CY  - Heidelberg
A1  - Schmidt, Viviane Charlotte
N2  - The research focus of this thesis is two-fold. First, the newly implemented isochronous operation of the Cryogenic Storage Ring (CSR) in Heidelberg is presented. It enables the identification of the stored ion species, including molecular isobars. Here, the masses of the different beam components are measured through their flight time. The method is sufficient to resolve species with relative mass
differences of ? 10^?5 and relative beam fractions ? 10^?3. Furthermore, first attempts to remove unwanted beam-contaminants are presented.
The second research focus of this thesis is on the decay of highly-excited C_2^? dimers. In the underlying measurements, the anions were produced in a sputter source. Consequentially, a small fraction of the dimers had sufficiently high internal excitation to undergo spontaneous auto-detachment (AD) or auto-fragmentation (AF). Signals stemming from both of these processes were recorded at the CSR. Detailed rate calculations for the destructive decay channels, AD and AF, as well as radiative relaxation were carried out for a wide range of ro-vibronic states. The measured signals could be reproduced employing a decay
model. Furthermore, the millisecond AD signal of C_2^? already observed at multiple other facilities could be explained for the first time by a new mechanism of rotationally assisted auto-detachment.
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/35189/
Y1  - 2024///
ID  - heidok35189
AV  - public
ER  -