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Journal of Physics Conference Series

Effect of Projectile Coherence on Atomic Fragmentation Processes

Michael Schulz, Kisra Egodapitiya, Sachin Sharma, Aaron C. LaForge, R. Moshammer, Abdulqader Ali Hasan, D. H. Madison

Published Nov 5, 2012• 0 citations
Publisher

Abstract

We demonstrate that the projectile coherence can have a major impact on atomic fragmentation processes. This has been overlooked for decades in formal scattering theory and may explain puzzling discrepancies between theoretical and experimental fully differential cross sections for single ionization.
DOI
10.1088/1742-6596/388/10/102027

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An atom trapping technique for determining absolute, total ionization cross sections (TICS) out of an excited atom is presented. The unique feature of our method is in utilizing Doppler cooling of neutral atoms to determine ionization cross sections. This fluorescence-monitoring experiment, which is a variant of the “trap loss” technique, has enabled us to obtain the experimental electron impact ionization cross sections out of the Cs 6 2P3∕2 state between 7 eV and 400 eV. CCC, RMPS, and Born theoretical results are also presented for both the ground and excited states of cesium and rubidium. In the low energy region (<11 eV) where best agreement between these excited state measurements and theory might be expected, a discrepancy of approximately a factor of five is observed. Above this energy there are significant contributions to the TICS from both autoionization and multiple ionization.