| Autor: |
Tilmann D. Märk, Aleksandar Stamatovic, Linda Feketeová, G. Gluch, T. Tepnual, C. Mair, W. Schustereder, Paul Scheier, S. Matt-Leubner, S. Feil |
| Rok vydání: |
2005 |
| Předmět: |
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| Zdroj: |
Springer Series in Chemical Physics ISBN: 9783540230380 |
| DOI: |
10.1007/3-540-27362-x_20 |
| Popis: |
Total and partial cross-sections for electron impact ionization of CH 4 (and other hydrocarbon molecules) were determined from threshold to 1000 eV. Ion kinetic energy distributions were measured applying a deflection and retarding field method. The extraction of ions from the ion source was simulated fully three dimensionally including the presence of a guiding magnetic field for the electrons. Thereby discrimination factors were determined as a function of the initial ion kinetic energy. Multiplication of these factors with the ion signal leads to accurate relative partial cross-sections. By normalizing the sum of these partial cross-sections to an absolute value for the total cross-section taken from the literature absolute partial cross-sections were obtained that agree well with previous measurements where a complete collection of the product ions has been demonstrated. In addition, with the present method it is possible to determine cross-sections that are differential with respect to the initial kinetic energy of the ion. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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