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R. L. Mills

Publications and source records attributed to R. L. Mills.

3 recordsLinked to original sources

MHD Memes

The celebration of Allan Kaufman's 80th birthday was an occasion to reflect on a career that has stimulated the mutual exchange of ideas (or memes in the terminology of Richard Dawkins) between many researchers. This paper will revisit a meme Allan encountered in his early career in magnetohydrodynamics, the continuation of a magnetohydrodynamic mode through a singularity, and will also mention other problems where Allan's work has had a powerful cross-fertilizing effect in plasma physics and other areas of physics and mathematics.

physics.plasm-ph

Water bath calorimetric study of excess heat generation in 'resonant transfer' plasmas

Water bath calorimetry was used to demonstrate one more peculiar phenomenon associated with a certain class of mixed gas plasmas termed resonant transfer, or RT plasmas. Specifically, He/H2 (10%) (500 mTorr), Ar/H2 (10%) (500 mTorr), and H2O(g) (500 and 200 mTorr) plasmas generated with an Evenson microwave cavity consistently yielded on the order of 50% more heat than non RT plasma (controls) such as He, Kr, Kr/H2 (10%), under identical conditions of gas flow, pressure, and microwave operating conditions. The excess power density of RT plasmas was of the order 10 W / cm-3. In earlier studies with these same RT plasmas it was demonstrated that other unusual features were present including dramatic broadening of the hydrogen Balmer series lines, unique vacuum ultraviolet (VUV) lines, and in the case of water plasmas, population inversion of the hydrogen excited states. Both the current results and the earlier results are completely consistent with the existence of a hitherto unknown exothermic chemical reaction, such as that predicted by Mills, occurring in RT plasmas.

physics.plasm-ph

Spectroscopic study of unique line broadening and inversion in low-pressure microwave generated water plasmas

It was demonstrated that low pressure (~0.2 Torr) water vapor plasmas generated in a 10 mm inner diameter quartz tube with an Evenson microwave cavity show at least two features which are not explained by conventional plasma models. First, significant (> 0.25 nm) hydrogen Balmer_ line broadening, of constant width, up to 5 cm from the microwave coupler was recorded. Only hydrogen, and not oxygen, showed significant line broadening. This feature, observed previously in hydrogen-containing mixed gas plasmas generated with high voltage dc and rf discharges was explained by some researchers to result from acceleration of hydrogen ions near the cathode. This explanation cannot apply to the line broadening observed in the (electrodeless) microwave plasmas generated in this work, particularly at distances as great as 5 cm from the microwave coupler. Second, inversion of the line intensities of both the Lyman and Balmer series, again, at distances up to 5 cm from the coupler, were observed. The line inversion suggests the existence of a hitherto unknown source of pumping of the optical power in plasmas. Finally, it is notable that other aspects of the plasma including the OH* rotational temperature and low electron concentrations are quite typical of plasmas of this type.

physics.plasm-ph