Derivation and analysis of the Pariser-Parr- Pople model.
Second quantization formalism for deriving Pariser-Parr-Pople model for planar unsaturated molecules, analyzing model by propagator or Green function methods
Linderberg, J.↗
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Displacement correlations and frequency spectra for mass-disordered lattices. II.
Displacement correlations and frequency spectra for mass disordered lattices, deriving cluster expansion for phonon Green function
Goodman, B.↗
A model of interplanetary and coronal magnetic fields.
Green function solution to Maxwell equations for interplanetary and coronal magnetic fields above photosphere, considering field at source surface
Ness, N. F.↗
Radiative decay of polyatomic molecules.
Radiative decay of polyatomic molecules, applying Green function form for transition probability to decay of manifold of closely spaced coupled levels
Freed, K. F.↗
Extension of the integral formulation of scattering theory to Coulomb interactions.
Integral formulation of scattering theory extended to Coulomb interactions by expanding Green function and treating kernel singularities
Altick, P. L.↗
Radiation from sources in a moving, conducting medium.
Relativistic formulation of radiation for sources in uniformly moving isotropic dispersionless conducting medium in terms of Green functions
Kalafus, R. M.↗
Spherically symmetric boundary-value problems in one-speed transport theory
Boundary value problems in one speed transport theory, applying Green function technique to neutrons with spherical symmetry
Case, K. M.↗
Nonlinear spin-wave theory for the anisotropic Heisenberg antiferromagnet
Nonlinear spin wave theory for anisotropic antiferromagnetism, solving sublattice magnetization by thermodynamic Green function for temperature dependence
Flax, L.↗
Impedance of arbitrarily oriented cylindrical and helical antennas in magnetoplasma
Cylindrical and helical antennas impedance in cold magnetoplasma, using three dimensional integral involving Fourier transform and Green function
Weil, H.↗
Evaporation of He-3 atoms from liquid He-3/He-4 mixtures
Green function theory of evaporation of He 3 atoms from liquid He 3/He 4 mixtures, determining energy distribution
Hyman, D. S.↗
Thermodynamics of a Heisenberg ferromagnet in the random phase approximation
Green function used for thermodynamic model of Heisenberg ferromagnet in random phase approximation
Flax, L.↗
Time-dependent Hartree-Fock theory for atoms
Coupled and uncoupled versions of Hartree-Fock theory, calculating atomic system linear response to external time dependent perturbation and Green function
Jamieson, M. J.↗
Thermodynamics of Heisenberg ferromagnet in the random phase approximation
Heisenberg ferromagnet magnetic and thermodynamic properties in random phase approximation, determining magnetization and susceptibility with Green function theory
Flax, L.↗
Linear random operator equations in mathematical physics. II
Stochastic, random and ordinary Green function relations for two point correlation functions in mathematical physics
Adomian, G.↗
The acoustic response of rooms with open windows to airborne sounds.
The objective of the work described in this and the companion paper was to establish a theory for predicting the sound field generated in a room by a sonic boom incident on an open window. In this paper, some basic theoretical results are presented. First, the case of a normally incident harmonic wave was considered. Expressions for the pressure field were obtained by viewing the room as a terminated duct and by using a Green function method. The concept of mode excitation distribution functions was formulated and used to match the boundary conditions. This concept has been extended for oblique incidence. A modified form of Laplace transform technique was used to obtain expressions in the time domain for transient signals.
Vaidya, P. G.↗
Subsonic potential aerodynamics for complex configurations - A general theory
A general theory of subsonic potential aerodynamic flow around a lifting body having arbitrary shape and motion is presented. By using the Green function method, an integral representation for the velocity potential is obtained for both supersonic and subsonic flow. Under the small perturbation assumption, the potential at any point in the field depends only upon the values of the potential and its normal derivative on the surface of the body. On the surface of the body, this representation reduces to an integro-differential equation relating the potential and its normal derivative (which is known from the boundary conditions) on the surface. The theory is applied to finite-thickness wings in subsonic steady and oscillatory flows.
Morino, L.↗
A General Theory of Unsteady Compressible Potential Aerodynamics
The general theory of potential aerodynamic flow around a lifting body having arbitrary shape and motion is presented. By using the Green function method, an integral representation for the potential is obtained for both supersonic and subsonic flow. Under small perturbation assumption, the potential at any point, P, in the field depends only upon the values of the potential and its normal derivative on the surface, sigma, of the body. Hence, if the point P approaches the surface of the body, the representation reduces to an integro-differential equation relating the potential and its normal derivative (which is known from the boundary conditions) on the surface sigma. For the important practical case of small harmonic oscillation around a rest position, the equation reduces to a two-dimensional Fredholm integral equation of second-type. It is shown that this equation reduces properly to the lifting surface theories as well as other classical mathematical formulas. The question of uniqueness is examined and it is shown that, for thin wings, the operator becomes singular as the thickness approaches zero. This fact may yield numerical problems for very thin wings.
Morino, L.↗
Steady and Oscillatory, Subsonic and Supersonic, Aerodynamic Pressure and Generalized Forces for Complex Aircraft Configurations and Applications to Flutter
A general method for analyzing aerodynamic flows around complex configurations is presented. By applying the Green function method, a linear integral equation relating the unknown, small perturbation potential on the surface of the body, to the known downwash is obtained. The surfaces of the aircraft, wake and diaphragm (if necessary) are divided into small quadrilateral elements which are approximated with hyperboloidal surfaces. The potential and its normal derivative are assumed to be constant within each element. This yields a set of linear algebraic equations and the coefficients are evaluated analytically. By using Gaussian elimination method, equations are solved for the potentials at the centroids of elements. The pressure coefficient is evaluated by the finite different method; the lift and moment coefficients are evaluated by numerical integration. Numerical results are presented, and applications to flutter are also included.
Chen, L. T.↗