Collisionless damping of surface plasma oscillations and possibilities of its reverse at the interaction with charged particle flows
This paper is devoted to investigation of the interaction between the charged particle flows passing through the boundary of plasma-like media and surface oscillations.
Interaction of hot electrons with two-dimensional gas in semiconductor superlattices
Abstract We have studied the interaction of two-dimensional plasmons with a beam of charged particles consisting of hot electrons arising from the effect of the electric field in a two-layer heterostructure and a superlattice. The spectra of the eigen oscillations are obtained. Kinetic equations describing the wave-particle interactions are constructed. The instability growth rates are calculated for transverse oscillations. Numerical estimates are given for the structures on the basis of semiconductor, compounds. Frequency and energetic differences are analyzed for semiconductor two-layer heterostructures and superlattices having this heterostructure as a periodic element.
A technique for large-field, superficial electron therapy.
The application of electron beams to radiation therapy has received increased attention in recent years. This interest stems largely from the special characteristics of the electron depth-dose distribution; the fall-off in depth dose near the end of the range of the electrons is particularly rapid for electron beams having energies less than about 10 Mev. Such an electron beam is suitable for the treatment of widespread, superficial lesions, where it is desirable to minimize the dose to deep tissues. All the common sources of super-voltage x-rays, apart from radioactive substances, are inherently capable of producing an external beam of electrons, though with varying degrees of complexity. Electrons of about the energy suitable for superficial therapy (several Mev) may be used to produce an x-ray beam which is sufficiently penetrating for the treatment of even the deepest lesions. The Stanford medical linear accelerator was designed to provide both x-rays and electron beams. The accelerator and its applic...