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1.
Calculations of internal conversion coefficients (ICC) of the E1–E4 and M1–M4 transitions for nuclei in ions show that the relative changes i / i of the ICC i for deep inner subshells can differ significantly from the relative changes i/i of the electron densities i at the nucleus. For the K conversion i/ i are many times greater than i/i. Especially large deviations of i/ i are characteristic of transitions of high multipolarity; however, for the M1 transitions they can also be significant. Illustrations of various dependencies of i/ iare presented for the conversion in the regionZ-50.  相似文献   

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3.
In this paper we prove results in resonance scattering for the Schrödinger operatorP v=–h 2+V, V being a smooth, short range potential onR n . More precisely, for energy near a trapping energy level 0 for the classical system defined by the Hamiltonianp(x,)= 2+V(x), we prove that the scattering phase and the scattering cross sections associated to (P v, P0) have the Breit-Wigner form (Lorentzian line shape) in the limith0.  相似文献   

4.
The probability of the decay of a bound -meson is calculated using the theory of weak interactions with an intermediate boson. It is found that this theory, like all the others, cannot explain the experimental maximum atZ=26.
- K-
- K- . , , , Z=26.


I wish to acknowledge my indebtedness to Professor V. Votruba for suggesting the problem and for valuable discussions.  相似文献   

5.
The aim of this work was to study ferromagnetic resonance in the single crystal ferrite film with a small halfwidth of the resonance lineH hkl in the bandsX, K andQ. The changes of the resonance static magnetic fields, the effective magnetization, the magnetocrystalline anisotropy field andH hkl with the temperature and frequency were investigated.The author wishes to express her thanks to Dr. S. Krupika, CSc, Dr. Z. Frait, DrSc., Ing. J. Kantrek, CSc. and Dr. R. Gerber, CSc. for their valuable discussions. The author is also grateful to Mr. M. Janatka for carrying out the electron diffraction, and Ing. V. ik for his experimental assistance.  相似文献   

6.
The statistical properties of a parametric amplifier and a frequency converter are studied by means of quantum mechanical methods. The Schrödinger picture and the P-representation of the density matrix are used. Carrying out the Fourier transformation of the Liouville equation a partial differential equation for a generating function is obtained. The inverse Fourier transform of a solution of this equation is a time-dependent P-representationPN( 1, 2,t). For the parametric amplifier a relation is derived which enables us to compute the functionPA( 1, 2,t) = =1< 1, 2/ 1> is shown thatPA is classical distribution ifPN( 1, 2,0) is a positive distribution, while the P-representationPN( 1, 2,t) need not exist as a distribution and the P-representationPN( 1, 2,t) for the parametric frequency converter is constant along classical trajectories.The author wishes to thank Dr. J. Peina for stimulating discussions.  相似文献   

7.
In this paper, the Hierarchical Model is studied near a non-trivial fixed point of its renormalization group. Our analysis is an extension of work of Bleher and Sinai. We prove the validity of the -expansion for . We then show that the renormalization transformations around have an unstable manifold which is completely characterized by the tangent map and can be brought to normal form. We then establish relations between this result and the critical behaviour of the model in the thermodynamic limit.  相似文献   

8.
In a previous paper asymptotic creation and annhilation operatorsa ± # have been constructed by the Kato-Mugibayashi method from the creation and annihilation operatorsa # for spin 1/2 fields with an interaction Hamiltonian density which is an evendegree polynomial in the field with ultra-violet cut-off and its derivatives. For any eigenvector of the total HamiltonianH=H 0+H I partial isometries ± have been defined so thata ± # equal ± a # *± on the ranges ± of ±. Since the existence of a groundstate ofH has been proved, the existence of at least one pair ± follows. The purpose of this paper is to show that for any ± orthogonal to the distribution of spins and momenta of the interacting Schrödinger states exp[–itH]± approaches fort the distributions of spins and momenta of the free state exp[–itH 0] if a wave-amplitude renormalization is carried out in ±. This is achieved by studying the expectation values of the operators in themaximally abelian W*-algebra generated by operators of the form a*a, in terms of whichany information about spins and momenta can be expressed.Supported in part by the National Research Council of Canada.  相似文献   

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10.
It is shown that the Landau-Lifshitz pseudotensor vanishes for any Kerr-Schild metricg =n + 2Hl l satisfying the conditionS l =0. Some solutions verifying this condition are indicated.  相似文献   

11.
An analytic gravitational fieldZ (Z y ) is shown to include electromagnetic phenomena. In an almost flat and almost static complex geometryds 2 =zdzdz of four complex variables z=t, x, y, x the field equationsR Rz = –(U U Z ) imply the conventional equations of motion and the conventional electromagnetic field equations to first order if =(Z v) and =(z ) are expressed in terms of the conventional mass density function , the conventional charge density function , and a pressurep as follows: v=const=p/c 2–10–29 gm/cm3.  相似文献   

12.
Letu() be an absolutely integrable function and define the random process where thet i are Poisson arrivals and thes i, are identically distributed nonnegative random variables. Under routine independence assumptions, one may then calculate a formula for the spectrum ofn(t), S n(), in terms of the probability density ofs, ps(). If any probability density ps() having the property ps() I for small is substituted into this formula, the calculated Sn() is such that Sn() 1 for small . However, this is not a spectrum of a well-defined random process; here, it is termed alimit spectrum. If a probability density having the property ps() for small , where > 0, is substituted into the formula instead, a spectrum is calculated which is indeed the spectrum of a well-defined random process. Also, if the latter ps is suitably close to the former ps, then the spectrum in the second case approximates, to an arbitrary, degree of accuracy, the limit spectrum. It is shown how one may thereby have 1/f noise with low-frequency turnover, and also strict 1/f 1– noise (the latter spectrum being integrable for > 0). Suitable examples are given. Actually, u() may be itself a random process, and the theory is developed on this basis.  相似文献   

13.
A variety of rigorous inequalities for critical exponents is proved. Most notable is the low-temperature Josephson inequalitydv +2 2–. Others are 1 1 +v, 1 1 , 1,d 1 + 1/ (for d),dv, 3 + (for d), 4 , and 2m 2m+2 (form 2). The hypotheses vary; all inequalities are true for the spin-1/2 Ising model with nearest-neighbor ferromagnetic pair interactions.NSF Predoctoral Fellow (1976–1979). Research supported in part by NSF Grant PHY 78-23952.  相似文献   

14.
We consider a sequencev of non-stationary solutions of the incompressible 2D-Euler equation, locally bounded inL 2. We prove that if the defect measure is supported in a one-dimensional set (3) of some special type (which we call finite type), the weak limitv ofv is a solution of the Euler equations: our theorem is of the type concentration-cancellation.  相似文献   

15.
Zusammenfassung In dieser Arbeit werden die Erscheinungen der normalen und anomalen, durch Infrarotstrahlung verursachten und von uns schon früher an diesen Photokatoden beobachteten Ermüdung von Silber-Cäsium-Photokathoden untersucht. Diese Erscheinungen wurden an durchsichtigen sowie undurchsichtigen, durch verschiedene Technologien zubereiteten Photokathoden festgestellt. Es wurden Messungen der Strahlungsintensitäts-, Temperatur- und Spektralverteilungsabhängigkeit der normalen und anomalen Ermüdung durchgeführt. Es werden die Ursachen der Unübereinstimmigkeit im Vergleich mit Arbeiten von De Boer und Teves besprochen. Ferner wurden die Zeitverläufe der Ermüdung bei der Abwechslung der Bestrahlungs- und Dunkelzyklen studiert.
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, , . , . , . . .
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16.
In order to obtain sum rules and spectral representations the Hermiticity property , A = A, of observables is used. It is shown that for certain and the property turns out to be inconsistent with the commutation relations that contain A. The known Schwinger paradox is explained by this inconsistency.  相似文献   

17.
, , . , . .
The damping of particle oscillations in a general field with periodic structure I
A liner theory is derived, discussing the dynamics of particles in the region of an equilibrium orbit in a general electromagnetic field, which forms a periodic system. The total particle damping is determined from the Hamiltonian found and from dissipative forces brought out by a classical reaction radiation. Relations for the damping of the synchrotron oscillations are derived from the study of the appropriate phase space.
  相似文献   

18.
The ergodic properties of two stochastic models I and II are investigated. Each model is described by a fieldx(t),t > 0, on the lattice =Z d,d < . For I,x(t) evolves according to the equations wherex s (t) R for eachs eF. Here the {ws(t): s } are independent, one-dimensional Wiener processes, 2 is a bounded interaction between adjacent lattice sites, and the potentials 1 and 2 satisfy appropriate regularity conditions. It is shown that for each model,x(t) is a Markov process on an infinite-dimensional phase spaceX. The probability measures onX that satisfy the Dobrushin-Lanford-Ruelle (DLR) conditions are stationary for this process and have a mixing property. Moreover, for I any stationary, time-reversal-invariant probability measure that has certain regularity properties must satisfy the DLR conditions.This paper is based on a portion of the author's Ph.D. thesis.(2)  相似文献   

19.
In this paper, we prove the following improved Vitali–Hahn–Saks measure convergence theorem: Let (L, 0, 1) be a Boolean algebra with the sequential completeness property, (G, ) be an Abelian topological group, be a nonnegative finitely additive measure defined on L, {n: n N} be a sequence of finitely additive s-bounded G-valued measures defined on L, too. If for each a L, {n(a)}n N is a -convergent sequence, for each nN, when { (a)} convergent to 0, {n(a)} is -convergent, then when { (a)} convergent to 0, {n(a)} are -convergent uniformly with respect to nN  相似文献   

20.
The theoretical relations between v and measured stress changes are discussed and compared with experimental results. For instantaneous change in the strain rate, the first deviation of the stress increase from the linearity ( C ) can be used as a measure of v for small deformation only. The comparison of C with the extrapolated value A enables to reveal the presence of recovery. The comparison of stress changes measured after a given rate change at the same strain on unrecovering (low temperatures) and recovering (higher temperatures) samples enables to differentiate between various types of recovery.  相似文献   

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