EGAS41 - Swansea University

41 st EGAS CP 54 Gdańsk 2009
Coincidence investigations of zinc 4 1 P 1 excitation by electron
impact – feasibility study
M. Piwiński ∗ , ̷L. K̷losowski, D. Dziczek, S.Chwirot
Institute of Physics, Nicholas Copernicus University
ul. Grudziadzka 5 - 7, PL 87-100 Toruń, Poland
∗ Corresponding author: Mariusz.Piwinski@fizyka.umk.pl
The atoms with two valence electrons outside a relatively inert core i.e. alkaline earths elements
and associated group of atoms like Zn, Ca, Cd and Hg are still a challenge for both
theoretical and experimental investigations of electronic collisions [1]. Electron – photon
coincidence experiments are well known for providing more detailed information about
atomic scattering than any earlier technique and have stimulated studies of increasingly
complex collision systems.
The photon polarization analysis version of the method has been applied to study
electron impact excitation of zinc atoms. The geometry of the experiment is typical for
a coherence analysis technique with electron beam cross-fired with a beam of Zn atoms
propagating inside a vacuum chamber. 213.8 nm photons resulting from the a radiative
decay of the 4 1 P 1 state excited by electron impact are detected in a direction perpendicular
to the scattering plane and analysed (in coincidence with scattered electrons) for either
linear or circular polarisation.
The present work is a continuation of our previous coincidence studies of electron
scattering on Ca, Cd and He atoms [2,3,4]. We present first complete experimental results
for the electron impact excitation of the 4 1 P 1 state of Zn obtained for the incident electron
energy of 100 eV.
References
[1] S.A. Napier et al., Phys. Rev. A 79, 042702-1-11 (2009)
[2] D. Dyl et al., J. Phys. B: At. Mol. Opt. Phys. 32, 837-844 (1999)
[3] M. Piwiński et al., J. Phys. B: At. Mol. Opt. Phys. 39, 1945-1953 (2006)
[4] ̷L. K̷losowski et al., Meas. Sci. Technol. 18, 3801-3810 (2007)
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