Study of Astrophysically Relevant Hydrogen Chemistry: Combining an RF Ion Trap with a Cold Effusive Beam
Abstrakt
This contribution presents recent progress made with an ion trapping instrument which is operated in the Department of Surface and Plasma Physics of Charles University. A special feature of the experimental setup is the combination of a low temperature 22-pole trap (22PT) with a cold effusive source for neutrals.
This allows us to study the interaction of trapped ions with slow and cold neutrals. Using a discharge tube also radicals can be produced, especially H- or D-atoms.
Recent experimental progress includes the extension of the temperature of the neutrals, TACC, down to 4 K and various improvements on the accommodator for getting stable dissociation degrees. Using an MCP detector, the chemistry of both cations and anions can be studied.
The instrument is presently used to explore a variety of pure hydrogen reactions at low temperatures. As a typical result, the formation of H3 + via radiative and ternary association of H+ an H2 at 10 K will be discussed as well as the following formation of small hydrogen clusters.
The conclusion and outlook give some hints to planned activities such as determination of state specific rate coefficients, the role of nuclear spin, and deuteration.