Experimental study of the emission spread at gyrotron cathodes by current-voltage characteristics

A scheme for automated study of current-voltage characteristics of gyroresonance devices is developed. The effective emission spread at the cathodes of powerful gyrotrons is studied by analysis of current-voltage characteristics. Experimental data on the effective emission spread parameter for different modes are given. The permissible emission spread at the cathodes of powerful gyrotrons is estimated, and the dependence of the electron beam parameters on the cathode emission spread is presented. A complex measurement technique showing the contribution of different physical mechanisms to the cathode emission spread is proposed. Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 40, No. 4, pp. 506–516, April, 1997.     

Optimization of the Magnetron-Injection Gun for a High-Power Planar Millimeter-Wave Gyrotron

Radiophysics and Quantum Electronics - We have developed a method for optimization of a planar magnetron-injection gun (MIG) with allowance for the three-dimensional configuration of the...     

System for the formation of an electron beam in a 258 GHz gyrotron designed for experiments on dynamic polarization of nuclei

We consider the features of a system for the formation of an electron beam in a continuouswave high-stability gyrotron at the second gyrofrequency harmonic with an operating frequency of 258 GHz. The problems related to the maintenance of the required beam parameters are analyzed. The procedure and results of numerical simulation of the electron gun and collector of the gyrotron are described. The influence of various physical factors on the characteristics of the electronoptical system of the gyrotron are studied. The design of the electron beam formation system is described along with the results of measuring its parameters.     

Experimental studies of gyrotron electron beam systems

In order to provide electron beams of powerful gyrotrons, magnetron-injection guns operating in the regime of the temperature limited current are used. The electron beam quality and gyrotron performances are defined both by the cathode emission processes and the processes occurring in the electron beam during its formation and transportation. The results of measurements of the energy spectrum and velocity spread of the gyrotron electron beam in different regimes are given. Experimental data on the parameter of efficient emission inhomogeneity for different regimes are presented, as well as the dependencies of electron beam parameters on efficient inhomogeneity of the cathode     

Experimental study of the output radiation spectrum of a gyrotron with partial reflection of the output signal

We present the results of experimental studies of the effect of reflection of microwave radiation from a dielectric window on the frequency characteristics of the output signal of a technological gyrotron. It is shown that the spectrum width increases several times due to the effect of reflections. Institute of Applied Physics of the Russian Academy of Sciences, GYCOM Ltd., Nizhny Novgorod, Russia Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 43, No. 4, pp. 440–444, September., 2000.     

Numerical simulation and experimental study of magnetron injection guns of high-power shortwave gyrotrons

The results of numerical simulation and experimental study of magnetron injection guns for high-power gyrotrons that form intense helical electron beams are compared. Three types of beams are studied: those with regularly intersecting trajectories, laminar, and mixed (with irregularly intersecting trajectories). The corresponding guns differ in the angle of inclination of the emitting surface to the axis of axial symmetry. Numerical simulation was performed using the ÉPOS program, which takes into account the effect of the space-charge field on the velocity distribution. The experimental studies of the latter were performed by the retarding-field method. It is established that with allowance for temperature deformations of the electrode systems, the experimental data are in satisfactory agreement with the theoretical. It is shown that for a maximal beam current, the best velocity-distribution characteristics (velocity spread and pitch factor) are provided by guns that form laminar and boundary beams (an intermediate case between laminar and regularly intersecting beams).     

An Experimental Study of the External-Signal Influence on the Oscillation Regime of a Megawatt Gyrotron

Radiophysics and Quantum Electronics - The radiation-frequency locking by an external signal is experimentally studied for a megawatt gyrotron. An external signal from a magnetron is applied to the...