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51.
B. Tatischeff M. P. Comets Y. Le Bornec N. Willis B. Bonin J. C. Lugol B. Mayer Y. Terrien R. Beurtey A. Boudard J. M. Durand P. Fassnacht F. Hibou 《Zeitschrift für Physik A Hadrons and Nuclei》1987,328(2):147-149
Some evidence is presented for a narrow peak at 1969±2 MeV (FWHM=9±2 MeV) in the missing mass spectrum of the3He(p, d) reaction, with 3 standard deviations. The nature of this state, the mass of which is below the NN threshold, is discussed in connection with structures found in other experiments. 相似文献
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B. Blank J. -J. Gaimard H. Geissel K. -H. Schmidt H. Stelzer K. Sümmerer D. Bazin R. Del Moral J. P. Dufour A. Fleury F. Hubert H. -G. Clerc M. Steiner 《Zeitschrift für Physik A Hadrons and Nuclei》1992,343(4):375-379
Total charge-changing cross sections have been measured for8Li on C and Pb targets, for9Li on C, Al, Cu, Sn and Pb targets, as well as for11Li on C, Sn and Pb targets at about 80 MeV/nucleon. These data are compared to measured total reaction cross sections and Glauber-type calculations using Hartree-Fock density distributions. These comparisons allow to draw conclusions on the proton density distribution of the neutronrich lithium isotopes. The results show that even for the most exotic nucleus11Li the proton distribution is only very weakly influenced by the long tail in the neutron density distribution already established in several experiments. 相似文献
56.
Chepoi showed that every breadth first search of a bridged graph produces a cop-win ordering of the graph. We note here that Chepoi's proof gives a simple proof of the theorem that G is bridged if and only if G is cop-win and has no induced cycle of length four or five, and that this characterization together with Chepoi's proof reduces the time complexity of bridged graph recognition. Specifically, we show that bridged graph recognition is equivalent to (C4,C5)-free graph recognition, and reduce the best known time complexity from O(n4) to O(n3.376). 相似文献
57.
Hubert Kalf 《Journal of Differential Equations》2004,205(2):408-423
We show that the point spectrum of the standard Coulomb-Dirac operator H0 is the limit of the point spectrum of the Dirac operator with anomalous magnetic moment Ha as the anomaly parameter tends to 0. For negative angular momentum quantum number κ, this holds for all Coulomb coupling constants c for which H0 has a distinguished self-adjoint realisation. For positive κ, however, there are some exceptional values for c, and in general an index shift between the eigenvalues of H0 and the limits of eigenvalues of Ha appears, accompanied with additional oscillations of the eigenfunctions of Ha very close to the origin. 相似文献
58.
D. T. Le C. P. Morath H. E. Norton D. A. Cardimona S. Raghavan P. Rotella S. A. Stintz B. Fuchs S. Krishna 《Infrared Physics & Technology》2003,44(5-6):517-526
In this paper we report studies on normal incidence, InAs/In0.15Ga0.85As quantum dot infrared photodetectors (QDIPs) in the dots-in-a-well (DWELL) configuration. Three QDIP structures with similar dot and well dimensions were grown and devices were fabricated from each wafer. Of the three devices studied, the first served as the control, the second was grown with an additional 400 Å AlGaAs blocking layer, and the third was grown on a GaAs n+ substrate with the intention of testing a single pass geometry. Spectral measurements on all three devices show one main peak in the long-wave IR (≈8 μm). The absorption was attributed to the bound-to-bound transition between the ground state of the InAs quantum dot and the ground state of the In0.15Ga0.85As well. Calibrated peak responsivity and peak detectivity measurements were performed on each device at 40, 60, and 80 K. For the same temperatures, frequency response measurements from 20 Hz to 4 kHz at a bias of Vb=−1 V were also performed. The addition of the blocking layer was shown to slightly enhance responsivity, which peaked at 2.4 A/W at 77 K, Vb=−1 V and responsivity was observed to be significantly reduced in the single pass (n+ substrate) sample. The rolloff of the frequency response was observed to be heavily dependent on temperature, bias, and irradiance. The results from the characterization of each sample are reported and discussed. 相似文献
59.
本文运用信息保存法对低速二维的流动现象进行模拟,考察了低速条件下的有限平板绕流以及微槽道气体流动问题。研究表明:在对低速流动的模拟过程中,运用IP法在能够获得较好的结果的同时,具有比DSMC方法更高的计算效率。 相似文献
60.
There are several fuelling methods for tokamak plasma: pellet injection (PI), gas puffing (GP), neutral beam injection (NBI) and supersonic molecular beam injection (SMBI) .SMBI has been created in the Southwestern Institute of Physics, China. 相似文献