Forming a pulsed beam of anions via electron dissociative attachment to diatomic molecules

Negative ions (anions) are of great importance in various research fields, including studies of matter-antimatter interactions. Forming such ions is a much more difficult task than creating positive ions, as the additional electron must be attached to an atom or molecule, losing most of its kinetic energy. Such an attachment is possible in a well-known phenomenon of electron dissociative attachment to a molecule.

To provide a pure set of anions, diatomic molecules should be used in such experiments.

In the case, when an intense, pulsed beam of anions is required, the anions may be produced continuously inside an ion trap and stored for minutes and subsequently released in a controlled way in a single pulse.

We are designing an apparatus allowing the production of such negative ion beams. Details of the design will be discussed. Numerical analysis of the expected efficiency and purity of the anion sets will be presented and discussed.