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1.
M. Mayr K. -H. Speidel M. Knopp W. Karle T. Faestermann F. Hagelberg H. -J. Simonis P. N. Tandon J. Gerber 《Zeitschrift für Physik A Hadrons and Nuclei》1987,327(2):157-161
[Theg-factor ratio of the first excited 3? and 5? states in40Ca was measured to beg 3/g 5=1.01(10) employing the implantation perturbed angular correlation technique. The static hyperfine fields (SF) in Fe and Gd hosts were used. In addition the lifetime of the 5? state was measured to be τ=426(7)ps. The values of the SF in Gd and Fe hosts were deduced and compared with systematics in this element region. 相似文献
2.
Marlies Gerber 《Geometriae Dedicata》2003,98(1):123-160
We establish some criteria for the existence or nonexistence of focal points near closed geodesics on surfaces. These criteria are in terms of the curvature of the manifold along the closed geodesic and the average values of the partial derivatives of the curvature in the direction perpendicular to the geodesic. Our criteria lead to a new family of examples of surfaces with no focal points. We also show that if S is a compact surface with no focal points and an inequality relating the curvature of the surface to the curvature of the horocycles holds, then the horocycles (considered as curves in S) are uniformly C
2+Lipschitz. 相似文献
3.
NIKITIN S.; PR?TZEL-WOLTERS D. 《IMA Journal of Mathematical Control and Information》1991,8(4):431-439
In 1983 Morse proved, for unknown scalar one-dimensional linearsystems, the nonexistence of rational or polynomial universalstabilizers (UAS). In 1983, Nussbaum gave an example of an analyticUAS. In our paper, it is shown that there exist time-invariantpolynomial UAS's with multidimensional gain adaptation. Thedesign procedure is developed for linear, minimum-phase systemsof relative degree one. Convergence of the closed-loop systemis proved. Some numerical simulations are provided. 相似文献
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H. -J. Simonis S. Kremeyer F. Hagelberg U. Reuter M. Knopp K. -H. Speidel J. Cub W. Karle P. N. Tandon J. Gerber 《Hyperfine Interactions》1990,61(1-4):1351-1354
From hyperfine interaction studles on free single electron16O(3−) ions. in a time differential mode using the recoil distance technique. It is shown that these ions are polarized when emerging
from magnetized thin layers of Fe. The observed degree of polarization
, however, is smaller than expected from transient field measurements. 相似文献
7.
8.
K. -H. Speidel M. Knopp W. Karle U. Kilgus M. -L. Dong H. -J. Simonis F. Hagelberg J. Gerber 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(1):29-36
Transient field precessions have been measured with the first excited 2 1 + -state as probe for ions of28Si traversing Fe at vion?1v0 and 13v0(v0=c/137) and62Ni being stopped in Fe. The degree of polarization deduced for the Si ions, p1s=0.19(6), is consistent with low-velocity data. There is clear evidence that the field strength is attenuated by heavy ion beams. For the62Ni(2 1 + ) state at 1.173 MeV a g-factor value of g=0.34(7) was obtained in good agreement with a previous result. 相似文献
9.
10.
M. Knopp K. -H. Speidel F. Hagelberg H. -J. Simonis J. Gerber P. N. Tandon 《Hyperfine Interactions》1987,34(1-4):183-186
A new method to detect polarization pick-up by ions emerging from thin polarized ferromagnetic layers has been tested. The applied technique consists in the observation of attenuated-angular correlations and atomic spin precessions for single-electron ions recoiling through vacuum in weak transverse magnetic fields. The Coulomb-excited19F(5/2+) state at 197 keV was used as probe. The experimental concept is described and the expected effects are discussed using the perturbed angular correlation formalism for polarized hyperfine interactions. 相似文献