The survival rate of anions inside Penning-Malmberg traps

The behaviour of anions inside Penning-Malmberg traps was investigated for application in forming antiprotonic atoms in the AEgIS experiment. It was found that field detachment due to the trapping potential is unlikely to occur. Cooling interactions with electrons will occur below the energy threshold for detachment, however, interactions with cold antiprotons could promote detachment, although analysis is limited by the available data. The Coulombic cooling between species can be modelled using a stopping-power formulation that has been developed. This is extended to consider detachment interactions, as well as a heavy particle as the cooling species.