Abstract
Internal conversion of the 14.4-keV transition in the outer shells of following the decay of has been examined at 0.05% momentum resolution. The intensity of the conversion in the outermost shell, in the free atom, relative to that of the shell shows a dependence on the chemical environment of the decaying atom. ions from an electromagnetic isotope separator were deposited at <25 eV on the surface ("oxide state") or were allowed at 500 eV to penetrate a natural graphite crystal lattice ("metallic state") where oxidation could not occur. The intensity ratio ("oxide") is 0.024±0.002 and ("metal") is 0.034 ±0.003. The -shell line shapes show less low-energy tail than the lines (which are only ∼0.7% lower in energy), an effect probably due to less outer-shell electron shakeoff in the case of the lines. This result throws doubt on the accuracy of the analyses of previous experiments in which the outermost-shell conversion lines were not well enough resolved to observe this effect and in which the assumption of similar line shapes were used.
- Received 25 January 1971
DOI:https://doi.org/10.1103/PhysRevC.3.2285
©1971 American Physical Society