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Research was conducted to examine the performance of high-critical temperature superconducting quantum interference devices (SQUIDs) with resistively shunted inductances. It was found that the voltage modulation depth Delta-V of shunted 83 pH SQUIDs was substantially larger than that of unshunted SQUIDs with similar parameters and increases with the parameter gamma = R(sub n)/R(sub s) as expected from theory. Results indicate that significant improvements in high temperature superconducting SQUID magnetometer performance can be achieved by resistively shunting the SQUID inductance.

The Air Force Research Laboratory RKO source has recently demonstrated the ability to convert electron beam power to Rf power until the termination of the electron beam pulse, achieving a power of 1.5 GW at an energy of 170 J. These results represent an increase in power of 25-30% in power and energy extracted from this source. This paper discusses the principal research areas encountered in lengthening the RF pulse (FWHM) from 50 ns to the present 120 ns and the associated increase in the RF energy. Index Terms - Gigawatt, klystron, microwave, RF, RKO.

The growth-linked phosphoprotein B50/GAP-43, related to axonal growth and regeneration, were isolated during the analysis of superior temporal gyrus of 7 control and 8 Alzheimer disease (AD) postmortem human brains. Neuritic plaque density is unrelated to differential distribution of phosphorylated and dephosphorylated B50/GAP-43 in ordinary and AD brains, which is connected with neurofibrillary tangle density.

By the use of a simple model, we explicitly incorporate the coupling between the driver cavity and the booster cavity in a relativistic klystron amplifier (RKA). We show that this RKA configuration may turn into an injection-locked oscillator only when the beam current is sufficiently high. Other features revealed by this model include: the downshifted frequency mode ('0' mode) is unstable whereas the upshifted frequency mode ('[Pi]' mode) is stable; the growth rate of the '0' mode is relatively mild so that the oscillation can start only in an injection-locked mode; the oscillation does not require the presence of reflected electrons; and the separation of the cavities must be sufficiently short. These, and other features, are found to be in qualitative agreement with the recent experiments on the injection-locked relativistic klystron oscillator (RKO) that were conducted at Phillips Laboratory.

Develops a self-consistent nonlinear theory of current modulation in an electron beam propagating through relativistic klystrons connected to a coaxial waveguide. Theoretical model of the beam-energy increase near the extraction cavity; Potential depression; Properties of the current modulation in a klystrons.