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101.
We experimentally demonstrate field-free, spin-selective alignment of ortho- and para molecular spin isomers at room temperature. By means of two nonresonant, strong, properly delayed femtosecond pulses within a four wave mixing arrangement, we observed selective alignment for homonuclear diatomics composed of spin 1/2 (15N) or spin 1 (14N) atoms. The achieved selective control of the isomers' angular distribution and rotational excitation may find applications to analysis, enrichment, and actual physical separation of molecular spin modifications. 相似文献
102.
One of the most frequently applied techniques to detect nanoparticles in air is analyzing laser light scattering. This technique is very flexible while offering high accuracy and reliability. Yet its functionality highly depends on the sensitivity of the measurement system components. Especially for miniaturized sensor devices with limited space, additional techniques are needed to preserve high intensity of scattered light. In our work we demonstrate a technique using two spherical ring mirrors to identify nanoparticles with diameters below 100 nm in a forward-scattering setup. We succeeded measuring polystyrene particles with diameters of 92 nm with a signal-to-noise-ratio of more than 10. 相似文献
103.
Kristof De Bruyn Robert Fleischer Patrick Koppenburg 《The European Physical Journal C - Particles and Fields》2010,70(4):1025-1035
The $B_{s}^{0}\to J/\psi K_{\mathrm{S}}$ decay has recently been observed by the CDF collaboration and will be of interest for the LHCb experiment. This channel will offer a new tool to extract the angle γ of the unitarity triangle and to control doubly Cabibbo-suppressed penguin corrections to the determination of sin?2β from the well-known $B_{d}^{0}\to J/\psi K_{\mathrm{S}}$ mode with the help of the U-spin symmetry of strong interactions. While any competitive determination of γ is interesting, the latter aspect is particularly relevant as LHCb will enter a territory of precision which makes the control of doubly Cabibbo-suppressed Standard-Model corrections mandatory. Using the data from CDF and the e + e ? B factories as a guideline, we explore the sensitivity for γ and the penguin parameters and point out that the $B_{s}^{0}$ – $\bar{B}_{s}^{0}$ mixing phase φ s , which is only about ?2° in the Standard Model but may be enhanced through new physics, is a key parameter for these analyses. We find that the mixing-induced CP violation $S(B_{s}^{0}\to J/\psi K_{\mathrm{S}})$ shows an interesting correlation with sin?φ s , which serves as a target region for the first measurement of this observable at LHCb. 相似文献
104.
Iris Fleischer Göstar Klingelhöfer Christian Schröder Daniel S. Rodionov 《Hyperfine Interactions》2008,183(1-3):193-198
Powders of Al substituted Ni-ferrites (NiAl x Fe2???x O4 x?=?0, 0.5, 1.0 and 1.5) were prepared using the calcination method. Mössbauer spectroscopy results of all samples show two well defined magnetic sextets corresponding to Fe3?+? ions in the A (tetrahedral) and B (octahedral) sites of the spinel structure. In addition, a quadrupole doublet with quadrupole splitting of (~0.53 mm/s) starts evolving upon Al substitution. This doublet is associated with a new Fe–Al-oxide phase. The X-ray diffraction patterns show, in addition to the original peaks, new peaks evolve and increase in intensity as the Al concentration increases, confirming the evolution of this new phase. 相似文献
105.
106.
Presented by I. Rosenberg. 相似文献
107.
Isidore Fleischer 《Mathematical Logic Quarterly》1973,19(13):205-206
108.
Isidore Fleischer 《Journal of Pure and Applied Algebra》1981,21(2):151-159
109.
110.