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101.
D. W. Nix J. C. McGeorge R. W. Fink 《Zeitschrift für Physik A Hadrons and Nuclei》1972,256(2):131-137
MeanL-shell x-ray fluorescence yields \((\bar \omega _L )\) have been measured by observingK andL x-ray spectra emitted in the decay of109Cd,145Pm, and153Gd with a high resolution Si(Li) x-ray detector. The results forZ=47, 60, and 63 are as follows: \(\bar \omega _L \) =0.0425±0.0064, 0.131±0.017, and 0.142±0.023, respectively. Additional values of \(\bar \omega _L \) from this laboratory atZ=55, 56, 57, 59, and 65 are also tabulated as are previous experimental values atZ=47, 60, and 63. For comparison, theoretical estimates of \(\bar \omega _L \) were computed using theoreticalL-subshell fluorescence and Coster-Kronig yields, together with subshell vacancy distributions calculated from the literature. The theoretical estimates atZ=47, 60, and 63, based on the subshell calculations of Chen, Crasemann, and Kostroun, agree well with experiment. 相似文献
102.
103.
J. F. Fink M. S. Jacobson L. F. Kinch J. Roberts 《Periodica Mathematica Hungarica》1985,16(4):287-293
In this paper we present a characterization of connected graphs of order 2n with domination numbern. Using this class of graphs, we determine an infinite class of graphs with the property that the domination number of the product of any two is precisely the product of the domination numbers. 相似文献
104.
The L1 subshell orbital electron capture probability PL1 in the decay of 33.4 y 207Bi to the 2339.89 keV level in 207Pb is measured to be 0.518 ± 0.081 (95% confidence) by a new method in which L1 subshell characteristic X-rays in the Lγ X-ray peak are observed in an Xγt coincidence mode with 1770.23 keV γ-rays. The value of PL2is 0.047 ± 0.015 (95% confidence). From these results a value of QEC = 39-8+21 keV is obtained for capture transitions to the 2339.89 keV level. The absence of K-capture to this level also is established by absence of K X-rays in coincidence with 1770.23 keV γ-rays. 相似文献
105.
106.
R. Klett D. Fink M. Mü ller H. Omichi F. Hosoi V. Hnatowicz J. Vacik G. Sanchez 《Radiation measurements》1997,28(1-6):51-53
Usually ion tracks are studies ex-situ, i.e. after removal of the ion-irradiated sample from the evacuated irradiation vessel. The exposure to ambient air leads to degradation effects which are frequently neglected and consequently have been studied rarely. They have never been explained consistently. In this work we compile and discuss them in the frame of today's general understanding of ion tracks in polymers. It appears that some pristine polymers such as polyethylene are covered by a surface layer which is badly permeable for gaseous contaminants. Ion irradiation leads to destruction of this protective layer so that oxygen and moisture from the ambient air can easily penetrate through the ion tracks, and eventually even into the surrounding pristine material. Moisture absorption along the tracks gives rise to some faint conductivity. Oxygen uptake adds new trapping centers to the existing ones along the tracks, so that on one hand an increased dopant uptake capability is recorded, and on the other hand oxygen-sensitive mobile dopants are immobilized along the ion tracks. Photooxidation processes contribute to the fading of the optical blackening of irradiated polymers. 相似文献
107.
H.J. Fink 《Physics letters. A》1973,43(6):523-524
The critical current and its dependence on the length of a thin superconducting wire between two normal metals and the voltage difference across the wire at the critical current is calcualted. The latter arises from the conversion of the normal current into supercurrent and vice versa at the contacts. It is found that the critical current is zero when the length of the wire is π coherence lengths or smaller. 相似文献
108.
M. Fink 《Nuclear Physics A》1974,221(1):163-172
The form factors of 4He and 16O are calculated using wave functions given by solutions of a generalized Hartree-Fock equation. No free parameters exist in the theory except the parameters of various phenomenological nucleon-nucleon potentials. The c.m. motion is treated exactly in the framework of a many body theory. The results strongly depend on the nucleon-nucleon potentials. 相似文献
109.
The X-ray intensity ratio has been measured, using radioactive sources and high resolution Si(Li) X-ray detectors over a range of 55 ? Z ? 94. The theoretical ratios are found to be underestimated at low Z in the calculations of Scofield and of Rosner and Bhalla. 相似文献
110.
With calibrated Ge(Li) x-ray detectorsK x rays in the conversion of the 30 keV isomeric transition in the decay of108mAg were observed in coincidence with 79 keV γ-rays. Thus, the fraction of 30 keV transitions which take place byK conversion was measured to be (2.44±0.23) × 10?2. Making use of a theoretical total conversion coefficient (K conversion contributes only a minor part of the total conversion coefficient), an experimental value of theK-conversion coefficient was obtained, αK=(1.07 ± 0.10) × 104 (where the error represents twice the standard deviation to which the error in the detector efficiency has been added linearly). This value agrees with the theory of Hager and Seltzer forM4 conversion. The energy of the cascading γ-ray was remeasured to be 79.20 ± 0.05 keV. 相似文献