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161.
D.E. Caro E. Gold A.G. Klein C.E. MacDowell G.I. Opat J.W.G. Wignall 《Nuclear Physics B》1973,52(1):239-247
We present differential cross sections for elastic d scattering at beam momenta 0.735 and 0.940 GeV/c and momentum transfers in the range 0.04<|t|<0.5(GeV/c)2. The d elastic differential cross section is expressed in terms of a deutron form factor and the I=0 t-channel exchange N amplitudes, enabling us to isolate the corresponding I=0 t-channel exchange cross sections. 相似文献
162.
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165.
G. Ransoné P. Sixel H.H. Kaufmann R. Klein H. Vogt H. Dreverman D. Kuhn J.P. Porte R.T. Ross F. Triantis K. Dziunikowska B. Muryn K.W.J. Barnham J. Wells P.R.S. Wright D. Dallman F. Mandl M. Szczekowski 《Nuclear Physics B》1980,167(3):285-291
The charged multiplicity distribution is presented for K?p interactions produced in the hydrogen bubble chamber, BEBC, using an r.f. separated, tagged K? beam of 110 GeV/c momentum. A comparison with K+p, πp and pp data at lower energies shows that the main features of the multiplicity distributions depend on energy and charge of the incident particles, but not on their strangeness. At high energies, only the energy is important. 相似文献
166.
The theory of two photon magnetooptic effects such as polarization rotation and circular dichroism is developed. An effect which has not been previously discussed, the optical analog of the Hanle effect, is proposed. 相似文献
167.
Budelmann D Schulz B Rübhausen M Klein MV Williamsen MS Guptasarma P 《Physical review letters》2005,95(5):057003
We report on the response of the electronic continuum from inelastic light-scattering experiments over an extended energy range between 1.970 and 4.504 eV in the superconducting state of Bi2Sr2CaCu2O8. The formation of a substantial Raman feature at shifts below twice the superconducting gap as well as the additional weight above this energy are found to be strongly dependent on the incident photon energy. For excitation wavelengths observed in ultraviolet, we find an enhancement of the integrated spectral weight below T(c). The resulting composite feature shows three distinct resonances at 2.5, 3.3, and 3.8 eV. We strongly suggest that the superconductivity-induced changes are the result of both the opening of a superconducting gap and the appearance of a collective mode. 相似文献
168.
The existence of an ice Ih/XI proton-ordering transition to a low-temperature ferroelectric phase has sparked considerable debate in the literature. Electronic density functional theory calculations, extended using graph invariants, confirm that a transition to a low-temperature ferroelectric phase should occur. The predicted transition at 98 K is in qualitative agreement with the observed transition at 72 K, and the low-temperature phase is the ferroelectric phase determined in diffraction experiments. The theoretical methods used to predict the phase transition are validated by comparing their prediction to the well-characterized ice VII/VIII proton-ordering transition. 相似文献
169.
Bartholomy O Credé V van Pee H Anisovich AV Anton G Bantes R Beloglazov Y Bogendörfer R Castelijns R Ehmanns A Ernst J Fabry I Flemming H Fösel A Freiesleben H Fuchs M Funke Ch Gothe R Gridnev A Gutz E Höffgen SK Horn I Hössl J Joosten R Junkersfeld J Kalinowsky H Klein F Klempt E Koch H Konrad M Kopf B Krusche B Langheinrich J Löhner H Lopatin I Lotz J Matthäy H Menze D Messchendorp J Morales C Novinski D Ostrick M Radkov A Reinnarth J Sarantsev AV Schadmand S Schmidt Ch Schmieden H Schoch B 《Physical review letters》2005,94(1):012003
Single pi(0) photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of approximately 98% of 4pi. Differential cross sections dsigma/dOmega have been measured. Complicated structures in the angular distributions indicate a variety of different resonances being produced in the s channel intermediate state gammap-->N(*)(Delta(*))-->ppi(0). A combined analysis including the data presented in this letter along with other data sets reveals contributions from known resonances and evidence for a new resonance N(2070)D15. 相似文献
170.
Simple models of earthquake faults are important for understanding the mechanisms for their observed behavior, such as Gutenberg-Richter scaling and the relation between large and small events, which is the basis for various forecasting methods. Although cellular automaton models have been studied extensively in the long-range stress transfer limit, this limit has not been studied for the Burridge-Knopoff model, which includes more realistic friction forces and inertia. We find that the latter model with long-range stress transfer exhibits qualitatively different behavior than both the long-range cellular automaton models and the usual Burridge-Knopoff model with nearest-neighbor springs, depending on the nature of the velocity-weakening friction force. These results have important implications for our understanding of earthquakes and other driven dissipative systems. 相似文献