This short course will present the state-of-the-art in understanding RF power phenomena that detrimentally affect space, aircraft and terrestrial communications. Dramatic increase in communications capacity, bandwidth, number of carriers and antennas poses new challenges in handling the high RF power. These problems become ever more acute and critical for emerging and future RF systems. The sho...

An analytic, first-order model has been developed to calculate irradiance thresholds for laser-induced breakdown (LIB) in condensed media, including ocular and aqueous media. A complete derivation and description of the model was given in a previous paper (Part I). The model has been incorporated into a computer code and code results have been compared to experimentally measured irradiance thre...

Multipactor discharges are widely observed in the accelerator field, and their suppression has been studied to improve performance. A dielectric-assist accelerating (DAA) cavity is a standing-wave that attains Q-value of over 100,000 at room temperature by using reflection dielectric layer; DAA expected be used with small RF power source high-duty operation. Thus far, maximum field cavities lim...

RF breakdown studies are presently being carried out at SLAC with klystron cavities in a traveling wave resonator (TWR). Different kinds of fabrication methods and several kinds of semiconducting and insulating coatings have been applied to X-Band TM010 cavities. RF breakdown thresholds up to 250 MV/m have been obtained. Dark current levels were found to be depressed in TiN-coated and single-po...

*Performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48. a)Consultant. b)Present affiliation: Voss Scientific, 416 Washington Street SE, Albuquerque, NM 87108. Figure 2. Breakdown thresholds for 0 o vacuum insulators. Figure 1. Dielectric Wall Accelerator (DWA). HIGH GRADIENT INSULATOR TECHNOLOGY FOR THE DIELECTRIC ...

We consider the relation between the breakdown scale of chiral perturbation theory, Λχ, for large values of N (flavor), and the scale associated with “new” physical thresholds. This question is addressed using both the linear σ model and an asymptotically-free gauge theory to describe the high energy dynamics. It is suggested that the massive physical threshold could be well above Λχ.

A numerical model combining the ultrafast radiative heat transfer and ablation rate equation for free electron density is proposed to investigate the transient process of plasma formation in distilled water. The focused beam propagation governed by the transient equation of radiative heat transfer is solved by the transient discrete ordinates method. The temporal evolution of free electron dens...