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71.
M. Della Negra D. Drijard H.G. Fischer G. Fontaine H. Frehse P. Frenkiel C. Ghesquière R. Gokieli P. Hanke W. Hofmann P.G. Innocenti W. Isenbeck E.E. Kluge V. Korbel S. Krzywdzinski D. Linglin A. Minten D. Wegener 《Physics letters. [Part B]》1975,59(5):481-484
The relative yields of pions of both charges have been measured in the c.m angular 5.5° ?θ1?21° in collisions at . The transverse momentum and x-dependence of these relative yields are presented and discussed. 相似文献
72.
The physical and metallurgical procedure in the preparation of semiconductor bicrystals is described, methods of seed orientation are given and precision limits are discussed. It is shown that medium angle boundaries can be grown at a high precision if proper techniques are used. A number microphotographs of grown grain boundary structures is given. 相似文献
73.
C.W. Darden H. Hasemann A. Krolzig W. Schmidt-Parzefall H. Schröder H.D. Schulz F. Selonke E. Steinmann R. Wurth W. Hofmann D. Wegener H. Albrecht K.R. Schubert P. Böckmann L. Jönsson 《Physics letters. [Part B]》1978,76(2):246-248
We observe a narrow resonance in the reaction e+e? → hadrons using the DASP detector at the DORIS storage ring. The mass is found to be (9.46 ± 0.01) GeV and the observed width is compatible with the storage ring resolution of ±8 MeV. The energy-integrated cross section results in an electronic width Γee = (1.3 ± 0.4) keV. 相似文献
74.
J. Engler B. Gibbard W. Isenbeck F. Mönnig J. Moritz K. Pack K.H. Scmidt D. Wegener W. Bartel W. Flauger H. Schopper 《Nuclear Physics B》1975,84(1):70-82
With a total absorption counter, inclusive neutron spectra have been measured at four ISR energies and at angles of 20, 66 and 119 mrad. The spectra show scaling behavior in the variables x and p⊥. Pion exchange is found to be important at large x values. 相似文献
75.
76.
Werner Bruckner Gerhard Ritter Horst Wegener 《Zeitschrift für Physik A Hadrons and Nuclei》1967,200(4):421-431
The Mössbauer effect studies of57Fe in the paramagnetic salt FeNH4(SO4)2·12 H2O reported byObenshain et al. were extended to higher values of the applied external magnetic fieldH a. The results are discussed in terms of the theoretical calculations given byWegener. The data can be fitted using a maximum internal fieldH max=(598±10) kOe and two atomic spin correlation times τc=2,4 · 10?9 sec andτ′ c=2,1 · 10?9 sec.τ c andτ′ c are independent ofH a and the temperatureT. It is assumed in the analysis that the distribution w(H) of the internal fields can be described by a continuous function of the Boltzmann factor type with two parameters. These two parameters are determined by the normalization and the macroscopic magnetization. 相似文献
77.
We excite ZnO samples with two-cycle optical pulses directly from a mode-locked oscillator with average powers of several tens of milliwatts. The emitted light reveals peaks at the carrier-envelope offset frequency f(?) and at 2f(?) in the radio-frequency spectra. These peaks can still be detected in layers as thin as 350 nm-a step toward determining the carrier-envelope offset phase itself. 相似文献
78.
We study the influence of the carrier-envelope offset phase of few-cycle pulses on nonperturbative resonant extreme nonlinear optics in a semiconductor. If the Rabi frequency becomes comparable to the light frequency, the different Rabi sidebands interfere around twice the laser center frequency, giving rise to a signal which strongly depends on the carrier-envelope offset phase. This signature should be measurable in GaAs samples. 相似文献
79.
C. Wegener A. Savitsky M. Pfeiffer K. Möbius H. J. Steinhoff 《Applied magnetic resonance》2001,21(3-4):441-452
Continuous-wave high-field electron paramagnetic resonance (95 GHz, 3.4 T) is performed on a spin label side chain located at residue position 171 in the proton entrance channel of bacterior-hodopsin The conformational differences of three bacteriorhodopsin mutants, the single mutant F171C, the double mutant D96G/F171C, and the triple mutant D96G/F171C/F219L, are reflected in different gxx and Azz tensor component shifts of the nitroxide side chain. The most polar microenvironment is found in the single mutant, whereas the open proton entrance channel reported for the triple mutant allows a reorientation of the nitroxide group towards a microenvironment of lower polarity and/or reduced hydrogen bonding. The experimental data of the double mutant are explained by a light-independent equilibrium of two nitroxide orientations with different polarities of the local microenvironment. Upon illumination the spectrum of the single mutant revealsg xx andA zz tensor component shifts which resemble those determined for the triple mutant in the dark. This result provides strong evidence for a light-induced opening of the proton entrance channel of the single mutant similar to that found in the unilluminated triple mutant, in agreement with electron diffraction data. 相似文献
80.