ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Laser resonance transitions between normally metastable states of antiprotonic helium atoms were induced making use of state dependent quenching effects caused by trace admixtures of H2 to the target helium gas. With this method of "H2-assisted inverse resonances" the decay rates of the states (n,l)=(39,l),l=36,37,38, and (38,l),l=35,36,37 of p¯He+ were determined as a function of the H2 admixture. The quenching cross sections at 30 K deduced therefrom for the states with n=39 were found to be of the order of the geometrical cross section for p¯He+–H2 collisons (2⋅10−15 cm2), with a moderate decrease with increasing l. Within a given cascade with constant v=n−l−1, the quenching cross sections for states with n=38 are smaller by a factor of 4–6 than those for states with n=39. © 1998 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.476579
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