VERY SLOW SPONTANEOUS DISSOCIATION OF CO2-ION STORAGE-RING( OBSERVED BY MEANS OF A HEAVY)

Long lived (0.8 ms, 6 ms, and > 3.8 s) states in CO2+ have been observ ed for the first time by monitoring beams of 75-300 keV ions in the io n storage ring ASTRID. It is the first experimental evidence that a do ubly charged molecule can be stable on a time scale of seconds. The re sults are theoretically interpreted by means of a multichannel Schrodi nger analysis based on ab initio computations of potential energy curv es and off-diagonal spin-orbit couplings. This analysis indicates that 3PI(nu=0) accounts for the long lived component. The two decay compon ents in the ms range probably derive from higher excited states in CO2 +.