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21.
Florian Kretschmer Stefan Mühlig Stephanie Hoeppener Andreas Winter Martin D. Hager Carsten Rockstuhl Thomas Pertsch Ulrich S. Schubert 《Particle & Particle Systems Characterization》2014,31(7):721-744
The unique properties of plasmonic nanostructures have fuelled research based on the tremendous amount of potential applications. Their tailor‐made assemblies in combination with the tunable size and morphology of the initial building blocks allow for the creation of materials with a desired optical response. In this respect, it is crucial to synthesize nanoparticles with a defined shape that are at the core of such developments. Moreover, the interaction of individual nanoparticles with an incident electromagnetic field cannot only be influenced by their structure, but in fact, also by their spatial arrangement to each other. To harvest such opportunities, a profound theoretical understanding of these interactions is required as well as concise strategies to create such ordered assemblies. A quantitative evaluation of their optical properties can only be conducted when discrete structures of high uniformity can be achieved. As a consequence, separation steps have to be applied in order to obtain materials of high purity and uniformity. This also allows for an easier structural characterization of the nanoparticles and their assembled superstructures. In this progress report, an overview about the current development in this field of research is provided. 相似文献
22.
The alignment of foil-excited hydrogen was determined by measuring the polarization of Ly- radiation in the particle energy region 23E190 keV. A change of sign at 45 keV is observed. 相似文献
23.
24.
Using singly or doubly reflected 270keV-ions from a Cu-surface at grazing incidence nuclear polarizations in7Li ofP I=(6.8±0.6) % orP I= (11.5±1.0) % and in14N ofP I =(14.8±1.0) % orP I=(20.0±1.0) % respectively, have been achieved. 相似文献
25.
26.
J. Döring L. Funke W. Wagner G. Winter 《Zeitschrift für Physik A Hadrons and Nuclei》1991,339(3):425-426
Excited states in the doubly-odd nucleus82Rb have been investigated via the reactions79Br(,n) and78Se(7Li,3n) using in-beam-ray spectroscopy. The level energy of the longlived 5– isomer has been determined to 68.3 keV which is below the energy of the 2– state found at 88.9 keV with a lifetime of=2.4(2) ns. A sequence of positive-parity states beginning with a 6+ level at 191.3 keV (=20(3) ns) and extending to a (10+) level has been interpreted to contain the two-particle configuration (g
9/2
9/2) and collective excitations. 相似文献
27.
28.
M. Jonker F. Udo J. V. Allaby U. Amaldi G. Barbiellini A. Capone W. Flegel M. Metcalf J. Meyer F. L. Navarria J. Panman A. M. Wetherell K. Winter F. W. Büsser H. Daumann P. D. Gall E. Metz F. Niebergall K. H. Ranitzsch P. Stähelin E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov A. Baroncelli B. Borgia C. Bosio F. Ferroni E. Longo P. Monacelli F. de Notaristefani P. Pistilli C. Santoni V. Valente 《Zeitschrift fur Physik C Particles and Fields》1983,17(3):211-217
The question whether scalar-type interactions contribute to weak interactions at large momentum transfer has been investigated by a measurement of the longitudinal polarization of positive muons produced in charged-current interactions of high-energy antineutrinos with iron. At an average momentum transfer <Q 2>=4 GeV2 the muon spin is found to be oriented forward with respect to the muon momentum vector, with an average polarization of 1.10±0.24, consistent with positive helicity. A limit on scalar contributions of σs, p/σtot <7% at the 95% confidence level can be deduced. A search for violation of time reversal invariance which could manifest itself by a polarization component perpendicular to the muon production plane gave a limit of σtv/σtot <16% (95% c.l.). It is concluded that the weak leptonic charged current retains its dominant vector and axial vector structure at large momentum transfers. 相似文献
29.
Clasine van Winter 《Integral Equations and Operator Theory》1987,10(1):96-139
This paper starts from a self-adjoint Schrödinger operator H(0) for three particles. If the interaction is dilation-analytic, H(0) has an analytic continuation H() (>0). G(t,) (–(±,a,) defined as strong limits, when t±, of t-dependent operators. The wave operators establish transformations under which the subgroups are similar to unitary groups. The scattering matrix determined by G(t,) is diagonal with respect to a.This work was supported in part by the National Science Foundation under grant DMS-8301096. 相似文献
30.
F. Bergsma J. Dorenbosch C. Nieuwenhuis J. V. Allaby U. Amaldi G. Barbiellini A. Capone Y. Eisenberg W. Flegel M. Jonker L. Lanceri M. Metcalf J. Panman D. Perret-Gallix R. Plunkett C. Santoni K. Winter I. Abt J. Aspiazu F. W. Büsser H. Daumann P. D. Gall T. Hebbeker F. Niebergall P. Schütt P. Stähelin P. Gorbunov E. Grigoriev V. Kaftanov V. Khovansky A. Rosanov L. Barone B. Borgia M. Diemoz U. Dore F. Ferroni E. Longo L. Luminari P. Monacelli F. de Notaristefani E. Valente CHARM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,40(2):171-192
We present here the final results of experiments searching for neutrino oscillations, carried out by the CHARM Collaboration. The data — taking took place in 1983. The first experiment was performed by exposing two detectors simultaneously to the CERN PS low energyv µ beam. In the second experiment the full CHARM detector was exposed to the wide-band horn-focusedv µ beam of the CERN SPS. Complete details of the experiments and data reduction are presented. No statistically significant signals for neutrino oscillations were observed. Our 90% CL limits in the appearance experiment (v µ→v e ) exclude Δm 2≧0.19 eV2 for complete mixing (sin22θ=1), and sin22θ≧0.008 for the region Δm 2≧30 eV2. These results, and the limits observed for (v µ→v x ) (disappearance of (v µ), are in agreement with those of most other experiments but exclude part of the region previously reported as a possible indication ofv µ→v e oscillations. 相似文献