Steady-State Orbitron Emissions
The Orbitron maser has been operated at a pressure of 2 × 10-6 in the steady state. Electrons are supplied to the device by an oxide-coated tungsten cathode placed inside the cylindrical cavity. The plasma-free emission corresponded to harmonically related steady-state narrow lines. The fundamental (lowest frequency) line corresponds to a resonance in the cavity system, which could be observed with a grid-dip meter.
The orbit theory of electrostatic electron cyclotron resonance masers
The orbit theory of the electrostatic electron cyclotron resonance maser (EECRM), which is similar to the orbitron maser, is presented based on models with both circular and noncircular steady-state electron orbits. In contrast to the nonlinear theory of the magnetostatic electron cyclotron resonance maser (MECRM), the concept of converting efficiency is introduced. The efficiencies for TE, TM, and TEM modes are calculated in various cases. Numerical analyses show that in the interaction process the radio-frequency (RF) fields attract energy mainly from the potential energy of electron beams. The nonlinear interaction mechanisms and the effects of some parameters are also studied. >
Persistence and Change in Minkowski Spacetime
There are famously two main metaphysics of persistence, namely three and four-dimensionalism. Both yield a particular solution to the so called puzzle of change. I argue that typical three-dimensionalist solutions to the puzzle face insurmountable difficulties even in the simplest relativistic setting, that of Minkowski spacetime