An interesting and satisfactory fluid model has been proposed in literature for the the description of relativistic electron beams. It was obtained with 14 independent variables by imposing the entropy principle and the relativity principle. Here the case is considered with an arbitrary number of independent variables, still satisfying the above mentioned two principles; these lead to condition...

The design and operating characteristics of relativistic, electron beam magnetrons are described. The magnetrons are comprised of a pulsed field-emission cathode (-360kV, ~15kA, -30nsec) and several coupled resonators embedded in the anode block. The tubes are designed to work at fixed frequency, in range from 2.3 to 5GHz. The peak powers generated are typically 500 to 1000MW. *This work was su...

I briefly review our current knowledge of the non thermal emission from galaxy clusters and discuss future prospect with Simbol-X. Simbol-X will map the hard X–ray emission in clusters, determine its origin and disentangle the thermal and non-thermal components. Correlated with radio observations, the observation of the non-thermal X-ray emission, when confirmed, will allow to map both the magn...

In this paper, we have investigated the effects of self-fields on gain in a helical wiggler free electron laser with axial magnetic field and ion-channel guiding. The self-electric and self-magnetic fields of a relativistic electron beam passing through a helical wiggler are analyzed. The electron trajectories and the small signal gain are derived. Numerical investigation is shown that for grou...

[ 1 ] Linear accelerators producing relativistic (5 MeV) electron beams are now down to a size that allows them to be flown on spacecraft and sounding rockets. This opens up new opportunities for atmospheric/ionospheric modification experiments where the mesosphere and lower thermosphere regions can be perturbed down to 40-km altitude. In this paper the relativistic electron beam injection proc...

The Free Electron Laser (FEL) can be considered a laser, even though the underlying emission process does not occur in an atomic or a molecular system, with population inversion, but in a relativistic electron beam, passing through the magnetic field of an undulator. Several parameters (such as gain, saturation intensity, etc.) are common to both devices and this allows a unified description. T...