共查询到20条相似文献,搜索用时 46 毫秒
1.
H. Grosse 《Physics letters. [Part B]》1977,68(4):343-346
We prove a theorem concerning the energies of the 2S and 3D states in a potential , where Vc is a non-singular confining potential. If is positive, then the 3D state lies above the 2S state, provided For Vc = rα, this corresponds to 0 < α < 2. 相似文献
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3.
We prove that the generalized eigenfunctions of the Schrödinger operator are continuous for potentials obeing the following assumptions: V=V+?V?,V±≥0,, ,. 相似文献
4.
John Lekner 《Physica A》1982,112(3):544-556
We derive comparison identities for waves satisfying the equation d2Ψ/dz2+q2(z)Ψ=0. One of these identities is used to show that to second order in the product (wavenumber component normal to interface) × (interface thickness), the reflection amplitude is given by , where l is a legnth determined by the deviation of the interface profile from a step, and q1, q2 are the normal components of the wave numbers in media 1 and 2 on either side of the interface. For the continuous interfaces discussed, l is about two-fifths of the 10–90 interface thickness. The corresponding formula for the transmission amplitude is . 相似文献
5.
K. Moriyasu T. Burnett D. Holmgren H.J. Lubatti D. Rees G. Swider B. Yuldashiev K. Dziunikowska A. Eskreys K. Eskreys A. Gula D. Kisielewska H. Rudnicka P. Stopa W. Ko R.L. Lander J.S. Pearson D. Pellett A. Zieminski 《Nuclear Physics B》1978,137(4):377-389
Double-scattering effects are studied in π?d interactions at 360 GeV/c. The partial cross sections are presented. The double-scattering probability per πd collision is found to be . We have extracted the partial cross section XN of the double-scattering plus interference contributions, and find that XN obeys KNO scaling. The data are compared with various theoretical predictions. 相似文献
6.
It is proved that the quantum mechanical Hamiltonian for bosons (resp, fermions) is bounded from below if N ≤ cbκ?1 (resp. ). H is unbounded from below if N ≥ cblκ?1 (resp. ). The constants cb and cbl (resp. cf and cfl) differ by about a factor 2 (resp. 4). 相似文献
7.
H. Braun M. Cornelssen H.-U. Martyn O. Erriquez S. Natali F. Romano D. Bertrand M. Csejthey-Barth J. Lemonne P. Renton P. Vilain D.C. Cundy T.I. Pedersen D. Waldren 《Physics letters. [Part B]》1973,47(2):185-188
The q2 variation of the factor in the decay K+→π0e+ν has been studied using a sample of even detected in the CERN 1.1 m3 heavy-liquid bubble chamber. The data are consistent with a linear development with λ+=0.027±0.008. 相似文献
8.
Given a mapping , whose bifurcation points accumulate at λ = Λ∞, it is shown that the iterates converge to a function ψ(μ,y)asp→∞, where X∞ maximizes . The function ψ is universal up to scaling in μ and y, and satisfies ψ(μ/δ,ψ(μ/δ,?y/α)) = ?α?1ψ(μ,y). This result generalizes the well-known Feigenbaum universal function g(y) with g(g(?y/α)) = ?g(y/α, which is the special case for μ = 0. 相似文献
9.
The longitudinal conductivity of a quasi-one-dimensional metal is calculated for the case T?ωD (ωD being the limiting phonon frequency) and ωDl1/v?1 where l1 is the effective mean free path determined by impurity and phonon scattering: is the impurity mean free path. The conductivity is σ = (c1e2/πS)l3iv?2ωDλT for li?lph, σ = (c2e2/πS)vωD(λT)?2 for li?lph, λ being the dimensionless electron-phonon interaction constant, c1, c2 ~ 1, S = axay is the (xy) area per one chain. 相似文献
10.
We derive and compare with experimental data the bound , where α is the fine-structure constant, mp the proton mass, ν0 the photo-pion production threshold, σtot and are the unpolarized total hadronic photo-absorption cross section on protons and the unpolarized forward differential cross section for proton Compton scattering at photon-lab energy ν′, and λ and ν1 are any real numbers. We derive similar bounds on proton and neutron magnetic moments. 相似文献
11.
G.W. Brandenburg W.B. Johnson D.W.G.S. Leith J.S. Loos J.A.J. Matthews F.C. Winkelmann R.J. Yamartino 《Physics letters. [Part B]》1973,44(3):305-309
Differential cross sections for center of mass scattering angles near 90° are presented for the reactions , and KL°p → KS°p in the momentum interval 1.0 to 7.5 GeV/c. The energy dependences of these cross sections are found to be equally well described by the parameterization: or . 相似文献
12.
Results are presented of a 12 event/μb bubble-chamber experiment; the reactions discussed in detail are .The K1 (890)?p channel is dominated by the forward peak. The suggestion of flattering at cos θ = 1 is more pronounced in ; which is mainly natural-parity exchange. Pseudoscalar exchange contributes to ; this is more sharply peaked in t. The value of is somewhat larger than the upper limit from the dominant natural-parity exchange. There is significant structure in .The K1 (1420)?p channel is much more pronounced at 3.3 GeV/c than at 3.13 GeV/c, but is not markedly peripheral. The width of the K1 (1420) in the 3.3 GeV/c data is 42 ± 12 MeV/c2.The cross section for agrees with that expected from , assuming a single t-channel exchange. Our measured density matrix elements are consistent with a strong pseudoscalar exchange. 相似文献
13.
Emission spectra for the electronic transitions , , , , , , , and of 4He2 are reported and the electronic structure of the triplet states associated with v = 0 of (1σg)2(1σu) nsσ and ndλ characterized. The energy levels comprising the and the manifolds exhibit strong channel mixing, while the mixing of the with the channel structure is relatively minor. Models based on multichannel quantum defect theory are used to aid in the spectral assignments and to correlate the observed level structures. We show that three-limit and two-limit models adequately represent the bulk of the observed and channel structures, respectively. 相似文献
14.
The J = 2?1 microwave spectrum of six isotopic species of HSiF3 has been observed and assigned in excited states of five of the six fundamental vibrations. The assignment is based on relative intensities, double resonance experiments, and trial anharmonic force constant calculations. Analysis of the spectra leads to experimental values for five of the constants, all three l-doubling constants qt, one Fermi resonance constant φ233, and one zeta constant .The harmonic force field has been refined to all the available data on vibration wavenumbers, centrifugal distortion constants, and zeta constants. The cubic anharmonic force field has been refined to the data on and qt constants, using two models: a valence force model with two cubic force constants for SiH and SiF stretching, and a more sophisticated model. With the help of these calculations, the following equilibrium structure has been determined: , , ∠HSiF = 110.64(±3)°, 相似文献
15.
A. Berglund T. Buran P.J. Carlson C.J.S. Damerell I. Endo A.R. Gillman V. Gracco R.J. Homer M.J. Hotchkiss A. Lundby M. Macri B.N. Ratcliff A. Santroni T. Tso F. Wickens J.A. Wilson 《Physics letters. [Part B]》1975,57(1):100-104
For the first time, the reactions π+p→K+∑+ and K?p→π?∑+ have been studied in the same apparatus. This has been done at an adequately high momentum (10.1 GeV/c) to allow a check of the prediction of exchange degeneracy, that the differential cross sections should be converging at high energy. We have measured the cross section for momentum transfers t between tmin and t = ?0.3 (GeV/c)2. We find that for both reactions the differential cross section shows an exponential fall, with no deviations right in to t =tmin (where some other experiments have shown a dip in the cross section). Furthermore, we find the magnitude of the differential cross sections to be closely similar at t = 0, with a ratio However, the slope for the positive reaction is about 19% steeper than that for the negative reaction. 相似文献
16.
We present approximate analytic calculation of the functional derivative , where Tc is the superconducting critical temperature and is the electron-phonon spectral function, within the “square-well model” for the phonon mediated electron-electron interaction and weak coupling limit is the Debye energy). It is found that where λ is the familiar electron-phonon coupling parameter and is a universal function of the reduced frequency . We compare this formula with accurate numerical results for several weak coupling superconductors. The overall agreement is good 相似文献
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18.
The exponent Δ3 for a Landau isolated point on a first-order transition line is evaluated to order ?2, ? = 4 ? d, for the case when the order parameters is a symmetric, traceless tensor of order 3. The result is . 相似文献
19.
G. Dehm G. Göbel W. Wittek G. Wolf G. De-Jong S. Tavernier P. Cornet P. Dufour F. Grard V.P. Henri R. Windmolders G. Charrière W. Dunwoodie A. Grant Y. Goldschmidt-Clermont F. Muller J. Quinquard 《Nuclear Physics B》1974,75(1):47-58
The decay branching ratios of K10 (1420) into K+π?, K0π+π? and K1+(892) π? are measured in the charge exchange reaction using data from a K+d bubble chamber experiment at 4.6 GeV/c incident momentum. For the branching ratio is obtained. The results are compared with previous measurements. 相似文献
20.
Amit Sur 《Solid State Communications》1976,18(6):755-756
The first ten moments of the infinite-temperature space and frequency dependent two-spin correlation functions, and are obtained for the one-dimensional anisotropic Heisenberg model for r = 0 and r = 1. These are compared with those previously known. 相似文献