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121.
The polarization observables for deuteron photodisintegration are given as Hermitean forms of theT-matrix elementst
i
. By inversion we are able to express a given productt
i
*
t
j
in terms of polarization observables. This allows (i) to derive linear relations between observables for unpolarized, circularly and linearly polarized photons, (ii) to construct explicitly complete sets of polarization observables, and (iii) to derive quadratic relations between observables.Supported by the Deutsche Forschungsgemeinschaft (SFB 201) 相似文献
122.
O. Uwira A. Müller J. Linkemann T. Bartsch C. Brandau M. Schmitt A. Wolf D. Schwalm R. Schuch W. Zong H. Lebius W.G. Graham J. Doerfert D.W. Savin 《Hyperfine Interactions》1997,108(1-3):149-154
Recombination of Au49+, Au50+, and Au51+ ions has been studied at the TSR. With Au50+ ions a storage lifetime of only 2 to 4 s was observed with the magnetically expanded electron beam of the cooler at a density
of ne = 107 cm-3. This short storage time is a consequence of the highest recombination rate coefficient ever observed with an atomic ion
(1.8·10-6 cm3 s-1 at zero relative energy Erel = 0 between electrons and ions). At about 30 meV a huge dielectronic recombination resonance is found with a record small
width of only about 15 meV. Such resonances fortuitously occurring near Erel=0 are probably the main reason for the enhanced recombination rates observed with Au50+, with Pb53+ (in a recent experiment at LEAR) as well as with other complex ions. For Au49+ and Au51+ the recombination rates are smaller by an order of magnitude.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
123.
124.
Markus Poppenberg Klaus Schmitt Zhi-Qiang Wang 《Calculus of Variations and Partial Differential Equations》2002,14(3):329-344
Variational techniques are applied to prove the existence of standing wave solutions for quasilinear Schr?dinger equations
containing strongly singular nonlinearities which include derivatives of the second order. Such equations have been derived
as models of several physical phenomena. The nonlinearity here corresponds to the superfluid film equation in plasma physics.
Direct methods of the calculus of variations and minimax methods like the Mountain Pass Theorem are used. The difficulties
introduced by the nonconvex functional are substantially different from the semilinear case.
Received: 21 March 2000 / Accepted: 23 February 2001 / Published online: 25 June 2001 相似文献
125.
R. P. Schmitt T. Botting G. G. Chubarian K. L. Wolf B. J. Hurst H. Jabs M. Hamelin A. Bacak Yu. Ts. Oganessian M. G. Itkis E. M. Kozulin N. A. Kondratiev V. S. Salamatin I. V. Pokrovsky F. Hanappe E. de Goès Brennand A. Huck L. Stuttgé E. Liatard J. Beene R. Varner M. Halbert N. Gan 《Physics of Atomic Nuclei》2003,66(6):1163-1167
The time scales for nuclear fission have been explored using both pre-and postfission neutrons and GDR gamma rays. Four systems were investigated: 133-MeV 16O + 176Yb and 208Pb and 104-MeV 4He + 188Os and 209Bi. Fission fragments were measured in coincidence with PPACs. The neutrons were detected using eight detectors from the DEMON array, while gamma rays were measured using the US BaF2 array. The pre-and postfission gamma rays were determined using moving source fits parallel and perpendicular to the fission fragment emission directions. The time scales for fission for the neutrons were determined using the neutron clock technique. The gamma-ray data were fitted using a statistical model calculation based on the code CASCADE. The results of the fits from both data types were used to extract nuclear friction coefficients, γ, and fission time scales. The γ values ranged from 7 to 20, while the fission times were (31–105)×10?21 s. 相似文献
126.
E. Hlawka Ch. Binder P. Schmitt H. -Chr. Reiochel H. Mitsch F. Schweiger P. Gerl 《Monatshefte für Mathematik》1970,74(3):277-288
Ohne Zusammenfassung 相似文献
127.
Günter Schmitt 《Journal of organometallic chemistry》1975,102(1):13-19
Oxidation of isomeric diisobutylaluminium-n-hexenolates with oxygen yields after subsequent acetolysis besides the expected hexenol acetates also hexanetriol triacetates. Their formation is explained by intramolecular epoxidation with alkylalkoxyaluminium peroxides formed during the oxidation. 相似文献
128.
129.
Intermediate mass fragments emitted in the reaction Ag+14N at 100, 160 and 250 MeV bombarding energy
L.G. Moretto S.K. Kataria R.C. Jared R. Schmitt S.G. Thompson 《Nuclear Physics A》1975,255(2):491-508
The fragments produced in the reaction between a 14N beam of various energies and a natural Ag target have been studied. The atomic numbers of the fragments have been identified up to Z = 17 by means of a E-ΔE counter telescope. The cross sections, the kinetic energy distributions as well as the angular distributions have been measured for each atomic number. The kinetic energy distributions show two components: a high-energy component (quasi-elastic), prevailing at angles close to the grazing angles and for atomic numbers close to Z = 7, and a low-energy component (relaxed), at energies close to the Coulomb repulsion energy, present at all angles and for all the Z. A detailed study of the relaxed components of the kinetic energy seems to account for both them means and the widths of these distributions on a purely statistical basis. The cross sections of the relaxed components appear to be quite large at low Z and to decrease rapidly to a fairly constant value in the region of 10 ≦ Z ≦ 17. A marked even-odd alternation in the cross sections is observed. The angular distributions are strongly forward peaked for Z < 7. For Z > 7 the forward peaking decreases rapidly until, for Z > 13, the limiting form 1/sinθ is attained. Evidence for the existence of a diffusion process along the mass asymmetry coordinate is discussed. 相似文献
130.
P. Schmitt E. Hlawka H. Reiter H. G. Feichtinger N. Hofreiter S. Grosser H. Rindler E. Kotzmann P. Michor F. Haslinger H. Mitsch H. -C. Reichel 《Monatshefte für Mathematik》1976,81(2):169-176
Ohne Zusammenfassung 相似文献