3D Imaging

by T. Einfeld, A. Chichinin, O. Ott, N. Gödecke, C. Maul, and K.-H. Gericke

** Why are photodissociations
so exciting?***Simply because without them there is no life
on earth and on a more fundamental ground of understanding: they are half
of a bimolecular reaction and they can be studied in detail.**

** These are the questions which can be answered:*

- Which electronic states are involved in the
absorption process?

- Which electronic states are involved in the
dissociation process?

- What are the products?

- What is the branching ratio?

- What are the quantum states produced in the
dissociation (J, v, E, m_{J})?

- What are the correlated quantum states?

- What is the angular distribution of the fragments?

- What is the velocity distribution, i.e. the
recoil in all three dimensions of space?

- What about the mechanism of the decay?

...

** Which Apparatus is used / useful?*

The recently developed 3D Imaging apparatus is designed to determine the three-dimensional (3D) momentum vector of a single reaction product by a combination of two well-known principles. The first principle is the resonance enhanced multi-photon ionisation / time-of-flight technique (REMPI-TOF) to obtain the momentum distribution of one reaction product in one dimension. The second principle is the detection by a position sensitive detector to obtain the exact position of the same arriving particle and therefore the momentum distribution in the remaining two dimensions.

Details:

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