Comparison of big event with calculations of the air shower development

The incidence of high energy hadrons and electron-photons in air showers at various stages of development is calculated. Numerical calculation is used to solve the diffusion equation for a nuclear cascade and analytical calculation for cascade shower induced gamma rays. From these calculations, one can get the longitudinal development of the high energy hadron and electron-photon components, and the energy spectra of these components at various depths of air shower development. The total number of hadrons (N sub H) and electron-photon components (N sub gamma) are related according to stages of the air shower development and primary energy. The relation of the total energy of hadron and electron-photon component above the threshold energy is given. The energy balance between both components is also a useful parameter to study high energy events accompanying air showers. The relation of N sub H and fractional hadronic energy E (sum E sub H sup gamma/sum E sub H sup gamma + Sum E sub gamma) is calculated. This relation is helpful to understand the stage of air shower development(t) and primary energy (E sub p)

Computation accuracies of boundary element method and finite element method in transient eddy current analysis

The computation accuracies of the boundary-element method (BEM) and finite-element method (FEM) in transient eddy-current problems are compared by using a slot-embedded conductor model and a diffusion model that can be solved theoretically. For computing the vector potential or magnetic flux density it is shown that larger time-step width can be chosen in the BEM than in the FEM method for the same accuracy </p

Eddy current and deflection analyses of a thin plate in time-changing magnetic field

Eddy current and deflection analysis of a thin-plate model in a time-changing magnetic field is described. The model is solved as a coupled problem in which the time-changing magnetic field induces eddy currents and the eddy currents cause deflection of the thin plate by the Lorentz force. The eddy current analysis and deflection analysis are performed by an integro-differential method using a current vector potential and a structural finite element method using beam elements, respectively. The formulations of the motional electromotive force and the Lorentz force for the thin-plate model are presented. In addition, the applicability of the proposed method is verified by using a cantilevered-beam model </p

Structure of air shower disc near the core

The longitudinal structure of the air shower disk is studied by measuring the arrival time distributions of air shower particles for showers with electron size in the range 3.2 x 10 to the 5.5. power to 3.2 x 10 to the 7.5 power in the Akeno air-shower array (930 gcm squared atmospheric depth). The average FWHM as a parameter of thickness of air shower disk increases with core distances at less than 50m. AT the present stage, dependence on electron size, zenith angle and air shower age is not apparent. The average thickness of the air shower disk within a core distance of 50m could be determined by an electromagnetic cascade starting from the lower altitude