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- #How to make bessel beam in cst microwave studio full#
- #How to make bessel beam in cst microwave studio code#
- #How to make bessel beam in cst microwave studio free#
Therefore, the problem of the late electrons emitted from the cathode was solved. In the latter case, they changed the emission mechanism to the photoemission where the electron bunch length is in the order of the laser pulse length. They reported that in order to solve the back bombardment problem, two approaches could be considered to compensate this effect in an RF gun: applying a transverse magnetic field at the thermionic cathode surface which reduced the problem somewhat as the first approach and replacing the identical LaB 6 cathode with a photocathode as the second approach. by using SUPERFISH and PARMELA in their work to simulate the back bombardment dynamics of electrons in RF guns. Back bombardment effects were studied in details in the report of Liu et al. They reported that with some geometry corrections, these multipole modes could be suppressed. cause turbulence to the performance of RF guns. Multipole transverse magnetic modes studied in details by Chae et al. They showed that a rapid acceleration to relativistic velocities reduces the emittance growth arising from the nonlinear space charge forces. The dependence of the space charge on γ (relativistic factor) for a simple distribution was studied by McKee and Mady. However, there are some limits on the maximum electric field resulting in RF breakdown. In such velocities, in the laboratory frame, self-fields become very strong, reducing the space charge effect, and thereby decreasing the growth rate of the emittance. The figure of merit of RF guns is that, they could produce tens of megavolts per meter surface fields which could quickly accelerate electrons to relativistic velocities. The accelerated bunches then deliver to the magnet compression unit which is inclusive of an alpha-magnet and some quadruples before injection to a linac,. Because of the nature of the EM fields, the emitted electrons will be bunched. In thermionic RF gun, electrons emitted from a circular cathode, are accelerated by Electro-Magnetic (EM) fields. Because an RF gun with thermionic cathode is economical and reliable in producing high quality electron beam, it is a suitable choice for using in infrared FEL preinjector. RF guns are classified by their cathodes. To create a high quality beam, people have used the compact electron sources such as RF guns.
#How to make bessel beam in cst microwave studio free#
The performance of the free electron laser (FEL), , depends critically on parameters of the electron beam. According to the results, for a stable operation of the RF gun, one should consider the nose cone in vicinity of the cathode surface to reduce the back-bombardment effect. Additionally, by using the developed code, the effect of wall structure around the cathode on the back bombardment effect has been studied.
#How to make bessel beam in cst microwave studio full#
It was also demonstrated that by using a continuous wave laser beam for heating the cathode, the emission pattern full width at half maximum (FWHM) of the transverse emission distribution is proportional to FWHM of the Gaussian profile for the laser beam.
#How to make bessel beam in cst microwave studio code#
Simulation results have been validated via comparison with the well-known simulation codes such as ASTRA simulation code and CST microwave studio, as well as other simulation results in the literature. According to the results, the electron bunch emittance varies considerably with the emission pattern. In the presented work, we developed a 3D simulation code to model the real process of thermionic emission and to investigate the effect of emission pattern, by considering geometrical constraints, on the beam dynamics. To study the quality of the beam in a compact electron source, the emission pattern effect on the beam dynamics should be investigated. Collaborative Workflows and Design of ExperimentĪntenna and microwave engineers, antenna system integrator, as well as electronic engineers who require electromagnetic simulation to solve their problems, should attend the e-seminar.Thermionic radio frequency gun is one of the most promising choices to gain a high quality electron beam, used in the infrared free electron lasers and synchrotron radiation injectors.Signal Integrity and Thermal Simulation for Printed Circuit Board.Users will be able to make necessary changes to the product quickly, improving engineering efficiency and further boosting innovation. In addition, the integration on the 3DEXPERIENCE® platform enables seamless collaboration workflows, even among different teams and departments. SIMULIA CST Studio Suite 2021 introduces a range of new enhancements and improvements to increase the versatility and performance in modeling, meshing and solver technologies exactly to solve these issues. Communication system design is getting challenging today since antenna, microwave component and electronics performances have to be proven when they are installed in their working environment.