Discovery of Multiple, Ionization-Created Anions in Gas Mixtures Containing CS2 and O2

Understand

The use of negative ions in TPCs has several advantages for high-resolution rare- event detection experiments.

• The DRIFT experiment, for example, has taken full advantage of this technique over the past decade in a directional search for dark matter.
• This paper focuses on the surprising discovery of multiple species of ionization-created CS2 anions, called minority carriers, in gas mixtures containing electronegative CS2 and O2, identified by their slightly different drift velocities.
• Measurements of minority carriers in gas mixtures of CS2, CF4 and O2 are reported in an effort to understand the nature of these charge carriers.