共查询到20条相似文献,搜索用时 15 毫秒
1.
E. Schneider 《Solid State Communications》1982,44(6):885-887
The temperature dependence of the soliton density ns(T) which has been studied in Rb2ZnCl4 by 87Rb NMR could be fitted to a classical formula using only one fit parameter. From our data we cannot confirm recent experimental results which yield a critical exponent for the soliton density. The results are discussed with respect to the free energy where the soliton density acts as the order parameter. Moreover, couplings to other degrees of freedom, e.g. the elastic strains, are considered. 相似文献
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A general theory of monodromy preserving deformation is developed for a system of linear ordinary differential equations , where A(x) is a rational matrix. The non-linear deformation equations are derived and their complete integrability is proved. An explicit formula is found for a 1-form ω, expressed rationally in terms of the coefficients of A(x), that has the property dω=0 for each solution of the deformation equations. Examples corresponding to the “soliton” and “rational” solutions are discussed. 相似文献
5.
I. Reineck B. Wannberg H. Veenhuizen C. Nohre R. Maripuu K.-E. Norell L. Mattsson L. Karlsson K. Siegbahn 《Journal of Electron Spectroscopy and Related Phenomena》1984,34(3):235-252
The outer valence region in CS2 has been studied by high-resolution UV photpelectron Spectroscopy. The spectra reveal detailed vibrational structure in the X2Πg, A2Πu, B2Σ+u and C2Σ+g bands. Some of the fine-structure peaks in the XBand Cbands are shown to be pressure-dependent. The reason for the pressure dependence is assumed to be inelastic scattering of electrons emitted in the adiabatic transitions. It is established that the two CI satellite bands present in the He(I)-excited spectrum contain vibrational structure. 相似文献
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Walter Wyss 《Reports on Mathematical Physics》1980,18(1):87-95
Let be a 1-algebra with identity. With we associate a quasi-algebra Q() consisting of sequences whose entries are elements of . For A,B in we give general expansions pertaining to (A+B)n, eA+B and eAeB. We also discuss the case where is the 1-algebra generate creation and annihilation operators. Another example deals with the 1-algebra of field operators. 相似文献
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J. Migdałek W.E. Baylis 《Journal of Quantitative Spectroscopy & Radiative Transfer》1979,22(2):113-125
Relativistic, single-configuration Hartree-Fock oscillator strengths for the lowest ns2S→np2P and np2P→nd2D transitions in the first few members of the silver (n = 5) and gold (n = 6) isoelectronic sequences have been studied, both with and without allowance for core polarization. Core polarization is included by introducing a polarization potential in the one-electron Hamiltonian and by employing the corresponding correction for the dipole-moment operator in the transition matrix element. The results obtained are compared with available experimental data and the influence of core-polarization effects on oscillator strengths is discussed. 相似文献
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M. Deutschmann G. Otter H. Böttcher H.J. Schreiber V.T. Cocconi G. Kellner D.J. Kocher D.R.O. Morrison H. Saarikko K.L. Wernhard D. Kuhn R.M. Eason B. Pollock F. Mandl M. Markytan 《Physics letters. [Part B]》1978,73(1):96-98
A total of 101 ω? decays have been found in K?p interactions at 10 and . The decay angular distribution has been fitted under the assumptions that the ω? has spin either . It has been found that the probability of isotropy (spin is less than one in a thousand, whereas the probability for spin is about 70%. Thus, we exclude the spin assignment. The lifetime of the ω? is found to be (1.41?0.24+0.15) × 10?10s, in agreement with our earlier result based on about of the present sample. 相似文献
9.
Ulrike Mohr 《Optics Communications》1982,41(1):21-26
The change of photon statistics of a nearly coherent single-mode light beam travelling through a saturable m-photon-amplifying or absorbing medium (m = 1, 2, …) is theoretically investigated. With the help of an approximation scheme valid for ? 1, Δn2 ? 2 ( mean value and Δn2 variance of the photon number) an analytical expression is derived for the quantity Δn2/. The results holds for arbitrary values of the initial population inversion and of the degree of saturation. It turns out that for both amplification and attenuation processes after sufficiently strong interaction Δn2/ tends to an asymptotic value. 相似文献
10.
W.K. Dagenhart P.H. Stelson F.K. Mcgowan R.L. Robinson W.T. Milner S. Raman W.K. Tuttle 《Nuclear Physics A》1977,284(3):484-500
Coulomb excitation of the nucleus 115Sn was studied with beams of 4He and 16O. Level energies, spins, mean-lives and B(E2) and B(M1) transition probabilities were obtained. Spin + states were observed at 497.35 and 1280.08 keV and spin + states were observed at 986.54 and 1416.78 keV. A state of 612.79 keV was observed to be indirectly excited by decay of the Coulomb excited states. Eleven B(E2) values and nine B(M1) values were obtained for the transitions between the low-lying states. In contrast to previous particle transfer results which suggested a clear distinction between shell-model and collective + and + states, our results suggest the collective strength is shared by the two + and two + states. 相似文献
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We present detailed evidence that one-parameter families of area-preserving maps exhibit cascades of period doubling with universal geometric scaling in the parameter. We relate this behaviour to a fixed point equation of the form and , Φ:2→2. In particular we argue that the scaling transformation Λ:2→2 is conjugate to the transformation Λ0:(x, y)→(λx, μy), with λ2 ≠ μ, and in fact λ2 >μ. We present some numerical evidence that …, …, …, where δ is the asymptotic ratio of the differences of the parameter values corresponding to the successive periods 2k described above. 相似文献
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H. Roos 《Physica A》1980,100(1):183-195
Given the C1-algebra of observables, the KMS condition is formulated in terms of the time evolution α1t of a set 0 ? () of “physical” states subject to certain natural conditions. α1t need not be defined by an automorphism group of . It is shown that, for a KMS state ω, α1t induces a 1-automorphism αωt of the von Neumann algebra πω()″ generated by the representation πω belonging to ω. 相似文献
13.
The vector polarization transfer coefficient Kyy′ and the tensor analyzing power Azz have been measured for the 2H()3He reaction at θ = 0° over an incident deuteron energy range from 1 to 15 MeV in 0.5 MeV steps. The results agree with the previous 2H()3He measurements of Simmons et al. and are nearly identical to the 2H()3H measurements of Clegg et al. in the region of overlap. The present results provide an accurate and complete set of the observables necessary to use the 2H(,)3He reaction as a source of polarized neutrons. 相似文献
14.
The decay of the 4G state of Nd3+ in LaCl3 and La(Cl99.6 Br0.4)3 was measured after pulsed laser excitation as a function of temperature. The decay rate is shown to depend besides the radiative transition on single-phonon relaxation between the states 4G () and 4G () and on multiphonon orbit-lattice relaxation from 4G to 2G. Partial substitution of Cl by Br only alters the radiative lifetime. 相似文献
15.
We suggest a dynamical mechanism (dominance of isoscalar meson exchange) which leads to an interpretation of the S(1930) meson in terms of a doublet of N resonances with JπC(IG)=2?+(0+, 1?). The presence of a doublet implies constructive interference in the p → p elastic channel and destructive interference in the p → n channel, in agreement with recent experimental evidence. Possible spin and isospin assignments are suggested for other structures seen in N cross sections near threshold. 相似文献
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The differential cross section and polarization for neutrons scattered from 10B have been measured at En = 2.63 MeV (Ex = 13.85 MeV). The results of this experiment and other available neutron scattering data in the range 1 < En < 4 MeV are interpreted through a single-level R-matrix calculation over the region 12 < Ex < 15 MeV. Based on this analysis the most probable Jπ assignment for the 14.0 MeV level in 11B is . The anomaly near Ex = 13.1 MeV can only be explained in terms of two overlapping levels having assignments of (, )? and (, , )+. 相似文献
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H.H. Bingham C.W. Farwell W.B. Fretter G.M. Irwin S. Kahn A. Lu B. Daugeras D. Fournier J. Hennessy M. Novak J.J. Veillet A.M. Cnops F.R. Huson R.I. Louttit D.J. Miller J.S. ONeall M. Di Carato M. Rollier J. Ginestet 《Nuclear Physics B》1973,52(1):31-69
Coherent production of final states from A ~ 20 nuclei by K? beams of 5.5, 10.0 and 12.7 GeV is analyzed. Final states with ? 2πO are included. Coherent production occurs (although forbidden via 0+ exchange) and is dominated by the 1 (890). The shape of the t distribution, the alignment of the produced meson and the ratio of the cross section on nuclei to that on hydrogen are consistent with optical model predictions assuming that 1 (890) are produced on single nucleons by exchange of isoscalar trajectories of natural parity (JP = 1?, 2+, etc.) and that the 1 (890) absorption in nuclear matter equals that of the K?. Coherent production (allowed via 0+, 1?, 2+, etc. exchange) is dominated by the Q phenomenon. A Dalitz plot and angular correlation analysis yields values for fractions, and shows that dominates the coherently produced Q. The helicity of the Q is found to be compatible with 0. The Q? -nucleaon total cross section is estimated to be 0.98?0.37+024 times the ? -nucleon total cross section from a comparison of the coherent Q-production cross section with corresponding hydrogen cross sections at 10 and 12.7 GeV. We observe coherent production of ω. The ration coherently produced in the Q mass region is (4 ± 1)%. Coherent production of is observed in the L region. Coherent production is not observed in the K4π channels. 相似文献
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D. Soldo V. Henč-Bartolić A. Peršin 《Journal of Quantitative Spectroscopy & Radiative Transfer》1979,21(1):85-87
The atomic-state densities of the 6s[1 ]0 metastable Xe energy level and of the 5s4P, 5s4P and 5s4PBr energy levels in an Xe-Br2 mixture have been determined as a function of current strength. 相似文献
20.
A.L.S. Angelis G. Basini H.-J. Besch R. Breedon L. Camilleri T.J. Chapin R.L. Cool P.T. Cox C. von Gagern C. Grosso-Pilcher D. Hanna J.T. Linnemann C.B. Newman R.B. Nickerson N. Phinney S.H. Pordes K. Powell J.M. Yelton 《Physics letters. [Part B]》1982,116(5):379-382
The invariant cross sections for π0 meson production in alpha—alpha and alpha—proton collisions at the ISR were meas- ured up to transverse momenta of and , respectively. These measurements are compared with π0 production in pp collisions at the same values of nucleon, and the variation of the nuclear A-dependence with pT is determined. 相似文献