Production of O− from CO2 by dissociative electron attachment

Dissociative electron attachment cross-section measurements for the production of O^? from CO₂ have been performed utilizing a crossed target-beam—electron-beam collision geometry and a quadrupole mass spectrometer. The relative flow technique is employed to determine the absolute values of cross sections. The attachment energies corresponding to the five cross-section maxima are: 4.4 ± 0.1, 8.2 ± 0.1, 13.0 ± 0.2, 16.9 ± 0.2 and 19.4 ± 0.2 eV. The cross sections at these maxima are: 1.43 × 10^?19 cm², 4.48 × 10^?19 cm², 8.1 × 10^?21 cm², 8.1 × 10^?21 cm² and 1.2 × 10^?20 cm², respectively.     

The work function of cathodes for electrons and the performance characteristics of Geiger-Müller counting tubes

Acta physica Academiae Scientiarum Hungaricae - The paper deals with investigations concerning the relation between the work function of GM counting tube cathodes and the performance...     

Mobility of mass-identified ions in neon and reaction rate coefficient for Ne+ + 2Ne → Ne+2 + Ne

The mobilities of mass-identified Ne⁺ and Ne⁺₂ ions in neon have been measured by the “four-gauze” electrical shutter method at 300°K. The reduced zero-field mobilities of Ne⁺ and Ne⁺₂ ions, corrected to 273°K, are 4.13± 0.04 and 6.20± 0.07 cm²V^?1sec^?1 respectively. The reaction rate coefficient for the termolecular ion-neutral association reaction is (4.6 ± 0.35) × 10^?32 cm⁶ sec^?1 and in the range from 2 to 10 V cm^?1 torr^?1 it does not depend on the electric field strength.     

Mobilities of H+3 and HeH+ ions in helium gas and rate coefficient for HeH+ + H2 → H+3 + He

The mobilities of mass-identified H⁺₃ and HeH⁺ ions in helium and the reaction rate coefficient for HeH⁺ + H₂ → H⁺₃ + He have been measured by a drift-tube quadrupole mass spectrometer at 300 K. The zero-field reduced mobilities of H⁺₃ and HeH⁺ ions, corrected to 273 K, are 31.0 ± 0.8 and 23.4 ± 0.6 cm² V^?1 s^?1 respectively. The reaction rate coefficient was found to be (1.26 + 0.16) × 10^?9 cm³s^?1 and was observed to be independent of the mean ion kinetic energy in the range from 0.04 to 0.3 eV.     

Cross section for Ly-α emission by electron impact on methane

Utilizing Ly-α emission cross sections for H₂ as secondary standards, absolute values of Ly-α emission cross sections for CH₄ have been obtained for electron impact energies varying from threshold to 100 eV. A crossed electron beam—molecular beam geometry was employed and the Ly-α radiation was detected at 90° and 45° with respect to the incident electron beam by a solar blind photomultiplier in tandem with an oxygen filter. The results are compared with previous measurements. Appreciable differences among the various experimental data are found.