Charge-changing reactions and their influence on the ion motion in a Penning trap

摘要

Charge-changing reactions can lead to a significant change of the ion motion which may result in the loss of the ions from the trap. For the present experiments singly charged gold clusters from an external laser vaporization source have been transferred into a Penning trap and transformed into dianions by use of an electron bath of simultaneously stored electrons. The dianions have been investigated by collisional activation and laser excitation where electron emission has been observed as a cooling mechanism. Electron emission doubles the value of the cyclotron radius and in addition, the ions acquire a finite magnetron radius. This leads to an extension of the radial distance of the ion motion from the trap's axis by a factor of about three.