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Positron lifetimes in silicone fluids
Il Nuovo Cimento B Series 10, 1969Measurements have been made to determine the long-lived component,τ 2, and its intensity,I 2, of positrons decaying in normal and degassed silicone fluids of different viscosity grades. The results show that the lifetime,τ 2, of the triplet positronium decreases as the length of the chain of the silicone fluids increases, though the change is quite ...
P. Sen, A. P. Patro
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Lifetime of positrons in an electron gas
Physics Letters A, 1969Abstract The positron lifetimes in an electron gas are calculated using the bound state concept of Bergersen. In order to explain the results of two-γ angular distribution, a fast exchange between the electron in the bound state and the free electrons outside it, is assumed.
J.G. Garg, B.L. Saraf
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Positron lifetime measurement in NaNO2
Applied Physics, 1979Positron lifetimes in NaNO2 were measured as a function of temperature. The lifetime spectra consisted of one component, and could not be resolved into two component. The positron trapping model is not applicable in this case. Observed changes of lifetimes around the transition temperature could not be understood only by the volume dilatation, but they
H. Kumakura +3 more
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Positron lifetime in polycrystalline gadolinium
Physica Status Solidi (a), 1984A. M. Gömez, J. Serna
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A modern positron lifetime spectrometer
Nuclear Instruments and Methods, 1978The construction of a positron lifetime spectrometer is described and the test results presented. A constant fraction timing discriminator and a special construction for the time-to-amplitude converter form the advanced and vital parts of the system, which is assembled using ECL components (MECL-III).
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Probing the Free Volume in Polymers by Means of Positron Annihilation Lifetime Spectroscopy
Polymers, 2023Fiorenza Quasso, Giovanni Consolati
exaly
Positron Lifetimes in the Alkali Halides.
1961The positron lifetimes in the alkali chlorides and sodium halides have been measured. Two lifetimes have been found in each of these materials, with a small fraction (of the order of a few per cent) of the positrons annihilating with the longer lifetime.
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