This paper describes an improved apparatus to measure dielectric constants and dissipation factors using a resonance technique. The measurements can be made rapidly and accurately without appreciable systematic error in the wide frequency range from 1 kHz to 100 MHz. This apparatus uses the half power-gap variation method or the half power-varying gap-immersion method for solid-plate specimens and the solid-plate displacement method for liquid specimens. The electrode system is 30 mm in diameter and has a shield ring to avoid the edge capacitance effect, guards against surface current leakage, and variable air capacitors to set the electrode gap at any arbitrary value. To detect a very small power loss, the resonance voltages in circuits with Q≂100 are stabilized to −86 dB at a constant ambient temperature. We use phase detectors so that the electrode gap and the voltage at resonance can easily be read from the digital panel meter and the digital voltmeter. No corrections are necessary even at a high frequency of 100 MHz. The accuracy of measurements made using the half power-varying gap-immersion method is within 0.2% for the dielectric constant and 3% for the dissipation factor without marked degradation over the entire frequency range.

Many models that include small extra space dimensions predict graviton states which are well separated in mass, and which can be detected as resonances in collider experiments. It has been shown that the ATLAS detector at the Large Hadron Collider can identify such narrow states up to a mass of 2080 GeV in the decay mode G → e + e − , using a conservative model. This work extends the study of the e + e − channel over the full accessible parameter space, and shows that the reach could extend as high as 3.5 TeV. It then discusses ways in which the expected universal coupling of the resonance can be confirmed using other decay modes. In particular, the mode G → γγ is shown to be measurable with good precision, which would provide powerful confirmation of the graviton hypothesis. The decays G → µ + µ − , W + W − , Z 0 Z 0 and jet-jet are measurable over a more limited range of couplings and masses. Using information from mass and cross-section measurements, the underlying parameters can be extracted. In one test model, the size of the extra dimension can be determined to a precision in length of 7 × 10 −33 m.

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The carbon rod placed on the axis of two stub pipes was heated by microwave discharge in helium gas at the atmospheric pressure. When the length of carbon rod inside the stub pipe was adjusted to 1/4 of wavelength of microwaves, the matching condition for microwave power input was satisfied well. The high density plasma was produced around the open ends of stub pipes and the carbon rod was heated to the temperature higher than 3000K. As a result, a part of carbon rod was completely evaporated within a few minutes after the application of microwave power of 1.2kW.

A two-terminal micrometer electrode system of 30mm diameter for the rapid and easy measurements of dielectric constant and dissipation factor over a wide frequency range from 1kHz to 100MHz is presented.To minimize the error in the measurements of dielectric constant and dissipation factor caused by the uncertainty of the specimen's mean thickness determination, a specimen's mean thickness measuring mechanism is introduced to the electrode system having a shield ring, which was developed for the measurement of the solid plate specimen of less than 1.5mm thickness.To improve the sensitivity of the loss measurement at high frequencies around 100MHz and the stability of the electrode's Q at low frequencies around 1kHz, guarded variable capacitance diodes have taken place of a variable air capacitor which is in parallel with the electrode and is used to establish the resonance at any arbitrary electrode gap length. When the half-power varying-gap