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In this paper we discuss the contributions to the amplitude of the 0νββ decay, mediated by the heavy neutrino, from the two kinds of pion-charge-exchange mechanisms. The pion-double-charge-exchange mechanism is much more important for the 0νββ decay in nuclei, compared to the pion-single-charge-exchange mechanism. [ABSTRACT FROM AUTHOR]

In a previous paper by Park and Rho, an SU(3) chiral bag or chiral hyperbag was constructed and studied in detail, with a focus on the Cheshire Cat structure of the hyperons. This paper supplies some of the details left out in that paper, i.e., calculational procedure of vacuum contributions, their divegence structure and subtraction procedure to the inertia parameters that figure in the hyperons. We calculate them numerically by means of eigenmode sums including all the quark eigenstates up to ¦ ER ¦=250. We are able to isolate the leading divergences, in particular, their chiral-angle dependences, and consequently make subtractions to make the inertia parameters finite and consistent, in a manner quite analogous to the SU(2) case. [ABSTRACT FROM AUTHOR]

Based on the resonating group method, transfer reaction form factors are derived in distorted wave Born approximation. As a direct consequence of antisymmetrization, renormalization operators of relative motion in entrance and exit channels are automatically included. These operators, when used in the passive core approximation, change the conventional reduced width amplitudes into those advocated by Fliessbach. In the present paper, however, his results are derived in a way which avoids the problematic use of non-orthogonal intermediate states in the cluster transfer approximation. It is proposed to use the conventional reduced width amplitudes, together with proper renormalization kernels, in order to separate structure effects from reaction dynamics (energy dependence, absorption etc.) which determines the actual importance of the renormalization operators in entrance and exit channels. [ABSTRACT FROM AUTHOR]

The rotational and vibrational level population distributions of ground and electronically excited states of several homonuclear and heteronuclear molecules are calculated for direct ejection, association, and associative ionization mechanisms of molecule sputtering. The cascade properties, formation mechanism, initial atom separation, and axis orientation to the surface are clearly reflected in the sputtered molecule distributions. In general, extensive non-Boltzmann rotational and vibrational distributions are predicted. The probability that an atom pair survives the ejection, for typical sputtering parameters, is high; approximately 50% for homonuclear molecules to near 100% for hydrides. The predictions are compared with experimental optical emission spectra in the accompanying paper. [ABSTRACT FROM AUTHOR]

In this paper we describe an attempt to isolate superheavy elements from Atlantis II hot brine deposits. Volatile, sulfidic elements (Cd, Pb) were isolated and investigated for spontaneous fission events with a mica-plastic solid state track detector sandwich. During nearly two years exposure time no spontaneous fission activity was observed. The upper limit for the concentration of superheavy elements (following this chemistry) in the Atlantis II-material is found to be 1.4·10g/g. This limit is more than one order of magnitude lower than the concentration of a spontaneous fission activity in material from the Cheleken hot brine, as observed by Flerov and coworkers. [ABSTRACT FROM AUTHOR]

Nuclear Structure superallowed Fermi β transitions; derivation of the coupling constant for the induced scalar interaction f from experimental data. Very recent works reported a significant improvement in the consistency of ℱ t values for superallowed Fermi β-decays. This fact led us to investigate some aspects which are not usually tackled in a study of this kind of transition. In a recent paper we suggested that an upper limit for the coupling constant f for the induced scalar interaction can be derived analyzing superallowed Fermi β-transitions. In the present work we revise and improve the method for the determination of f. The result obtained, f/ f=( − 0.4±1.4) × 10, agrees with the prediction of the CVC theory. [ABSTRACT FROM AUTHOR]

The collision-induced dissociation of 10 keV H ions incident on H has been studied in this paper. Total cross sections and angle distributions for the H-H, H-H and H-H fragmentations are given. Distributions over both angle and velocity have been measured for the H-H and H-H fragmentation. [ABSTRACT FROM AUTHOR]

In this paper the effect of biquadratic exchange on Curie temperature has been discussed on the basis of double-time temperature-dependent Green-function formalism with the utilization of Callen decoupling scheme. Calculation has been done for a spin-1 bcc Heisenberg ferromagnet by the method of Flax and Raich and it has been observed that the variation of Curie temperature with the biquadratic exchange parameter α obeys a law prescribed by the previous authors. [ABSTRACT FROM AUTHOR]

The mode structure and the diffraction losses of a Perot-Fabry-Interferometer filled with an active material are calculated analytically with a Green's function method. The active material is described by a complex susceptibility. The mode pattern and the diffraction losses derived here are in good agreement with the results of Fox and Li, who obtained the mode pattern and the diffraction losses of the decaying modes of a Perot-Fabry-Interferometer by a machine calculation. Furthermore the case of different dielectric constants between the active material and the outer space and the example of a Perot-Fabry-Interferometer with infinite mirrors are discussed. Throughout the paper only a single mode is treated and it is assumed that the inversion in the active material is constant. [ABSTRACT FROM AUTHOR]

The undulatory behavior in the velocity dependence of the total elastic cross-section Q( v) for atom-atom-scattering can be calculated by the semiclassical approximation. In a previous paper J numerical values of the classical deflection function, which are necessary to evaluate the amplitude of the extrema in Q( v), were reported for a Kihara-potential as a function of the reduced energy K and the potential parameter α. The present paper gives the correspondent reduced maximum phase shifts η ( K,α), which determine the location of the extrema. The results for the Kihara-potential are compared with similar calculations for a Lennard-Jones-( n, 6)-potential. [ABSTRACT FROM AUTHOR]

The interaction of N atoms each with 3 levels at random lattice sites with a set of cavity modes is considered. The optical transition between the lowest two atomic levels is taken into account explicitely assuming a Lorentzian line shape, whereas the third level just serves for the pumping process. If homogeneous inversion of the atoms is assumed, only one coherent mode oscillates in the steady state. It is the one being closest to the atomic resonance and having highest Q. If, however, in the next approximation a mode-dependent depletion of the excited atomic states is taken into account, with increasing pumping rate several modes may oscillate simultaneously. The behaviour of two such modes is treated in detail and it is shown, that one obtains a stable configuration. Using a higher approximation the nonlinear interaction between these two modes brought about by the amplifying material is studied in detail. As a special result one obtains a repulsion of the frequencies of the modes as a function of pumping power in accordance with gaslaser experiments. Quantum noise effects are neglected throughout the present paper. [ABSTRACT FROM AUTHOR]

The results of the preceding paper are specialized to three-atomic molecules in which the three atoms are allowed only small vibrations about their equilibrium positions. This restriction to the vibrational amplitudes makes a perturbation calculation suitable. A sketch of the zero order approximation has been given in this paper, and it has been shown - at least for a symmetrical molecule of the type AB - how the limiting case of the rigid body may be obtained for which there exist the well-known formulas of Wang. [ABSTRACT FROM AUTHOR]

On the basis of the investigation carried out in this Laboratory, a relationship has been worked out between the absorption coefficient of a liquid and the overall efficiency of a quartz transducer vibrating in that medium in Part I of the paper. In this paper a similar relationship is established between the absorption coefficient of the liquid and the net ultrasonic efficiency of the crystal. [ABSTRACT FROM AUTHOR]

The possibility that an I=5/2, Y=1, M=1,470 MeV isobar really exists is analyzed, using the experimental data reported in several papers. The existence of such an isobar in an L=1 35-plet, was already suggested by the authors. [ABSTRACT FROM AUTHOR]

Applying the non-Markoffian master equation discussed in a previous paper to the test case of an exactly solvable model we study here the theory of the damped harmonic oscillator. The results confirm the criterion for the applicability of the Born approximation in which our master equation is valid. On the other hand, the present paper generalizes Markoffian theories of the damped oscillator. [ABSTRACT FROM AUTHOR]

In the case of one-way coupling, two-group transport theory specializes in a non-trivial way through the fact that additional discrete eigenfunctions occur within the range of continuous eigenfunctions. This problem is discussed in the present paper. Additional eigenvalues and eigenfunctions are presented. The full-range completeness theorem as well as the orthogonality and normalization relations are given. Expansion coefficients of the infinite-medium Green's function are presented as an example. [ABSTRACT FROM AUTHOR]

In an earlier paper it was shown by means of the Faddeev equations that the reduction of the three-body problem to formal two-body equations with energy-dependent complex potentials - a procedure which was already well known for separable potentials - can be generalized rigorously to arbitrary potentials. In the present paper we show that the projection operator approach of Feshbach appears as a special, and in a certain sense singular case of our general treatment. Optical potentials for rearrangement scattering are given explicitly and questions of how to calculate them are discussed, showing that the Faddeev approach is better suited in these respects. [ABSTRACT FROM AUTHOR]

We start from a density matrix equation in its most general form. It comprises the action of external fields on the system, internal interactions, as well as the action of dissipative mechanisms (heat-baths or reservoirs), which may be Markoffian or non-Markoffian. We then define a distribution function of a type introduced previously by Haken, Risken, Weidlich for atoms. This distribution function, f, which is now formulated quite generally with aid of projection operators, P, establishes a connection between the P' s and classical variables v. By means of f it is possible to exactly calculate all quantum mechanical expectation values by pure c-number procedures. If the basic density matrix equation is Markoffian, it is even possible to calculate all time-ordered multitime averages by c-number procedures using f, as had been demonstrated by Haken, Risken and Weidlich. In the present paper we derive in an explicit way an exact c-number partial differential equation for f. It contains derivatives of arbitrarily high order. In important classes of problems, it can be reduced to an ordinary FokkerPlanck equation, however. Our new equation has many applications, e.g. in the quantum theory of lasers, nonlinear quantum optics, spinresonance, and spin-wave-theory, as will be demonstrated in forthcoming papers. We wish to thank Prof. W. Weidlich and Dipl. Phys. H. Vollmer for several valuable discussions. In addition, H. Vollmer has kindly checked our calculations. [ABSTRACT FROM AUTHOR]

The present paper determines the spectral functions of the Greens-functions for quasiparticles defined in a previous paper by a variational procedure minimizing the thermodynamic potential Ω( T, V,μ). An approach for generalizing the results to an inhomogeneous model (e.g., a lattice) is proposed. [ABSTRACT FROM AUTHOR]

The functional formalism described in a preceding paper, leads to a great number of integral equations for molecular distribution functions. Some of them have a certain symmetry property which, in the case of the pair distribution function includes symmetry with respect to the permutation of particles. This symmetry condition is necessary for any self consistent approximation. Among all integral equations known to date only the PY and the HNC equations satisfy this condition. In this paper we derive some new symmetric equations. Integral equations which are obtained with the help of the Percus method, involving n-particle distribution functions ( n > 2), cannot be symmetric with respect to the interchange of particles. [ABSTRACT FROM AUTHOR]

We set up an effective Hamiltonian for an optical parametric oscillator. It contains the Bose operators of the three modes, signal, idler, and pump and their coupling to heat baths. This Hamiltonian is shown to be equivalent to a set of equations of motion, derived in a previous paper (I) from a microscopically exact Hamiltonian, provided that the heat baths are chosen in an adequate way. The comparison with the laser Hamiltonian makes clear the close analogy of the underlying elementary processes of spontaneous emission from atoms and spontaneous parametric emission from light modes in nonlinear media. The Hamiltonian is used to derive a master equation for the statistical operator of the three-mode system. In the coherent state representation this master equation transforms into an equivalent c-number Fokker-Planck equation without any approximation. The solution is obtained below threshold by linearization and above threshold by quasilinearization of the nonlinear dissipation coefficients. The results agree with those which were obtained by quantum mechanical Langevin methods in a previous paper (I). [ABSTRACT FROM AUTHOR]

If a quantum-mechanical potential is introduced the calculation of the quantummechanical binary distribution function for a system with Coulomb interaction is reduced to the well-known mathematical formalism of classical statistical mechanics in the case of nλ≪1 (λ being the thermal wavelength). The two-particle quantummechanical potential is determined by the two-particle Slater sum. In this paper we calculated the two-particle Slater sum using an expansion according to e and the resolvent formalism. From the binary distribution function the correlation energy and the free energy as well were determined up to order e. Symmetry effects were taken into account. [ABSTRACT FROM AUTHOR]

The optical absorption coefficient has been calculated in the case of resonant band modes, using the frequency spectrum discussed in a previous paper 1. The width of the absorption line does not show any great variation with the density of impurities whereas the position of the absorption maximum is shifted. [ABSTRACT FROM AUTHOR]