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Rotational-temperature determination in flowing nitrogen using an electron beam
| Content Provider | HathiTrust Digital Library |
|---|---|
| Author | Lillicrap, D. C Lee, L. P |
| Editor | D.C. Lillicrap L.P. Lee |
| Organization | Langley Research Center. |
| Description | The measurement of rotational temperature by the electron-beam fluorescence technique is investigated for temperatures between 78 K and 300 K by using the 0-0 band of the nitrogen first negative system. Existing methods for calculating the rotational temperature from electron-beam spectra result in values which are higher than the true temperature and the error increases with density and electron-beam current. The errors are believed to arise through neglect of the effects of secondary electrons. Excitation by low-energy secondary electrons can increase the population of the sparsely populated rotational ground states at the expense of the abundantly populated states. This secondary excitation is proposed as the cause of the error in the calculated rotational temperature and a theoretical study determines that the density and beam current govern the excitation rate. Rotational-temperature measurements are made in a flowing stream of nitrogen at a known temperature for a range of densities and beam currents |
| Volume Number | NASA TN D-6576 |
| Language | English |
| Publisher | National Aeronautics and Space Administration |
| Publisher Date | 1971-01-01 |
| Publisher Place | Washington D.C. |
| Access Restriction | Open |
| Rights License | Items in this record are available as Public Domain, Google-digitized. View the access and use profile at http://www.hathitrust.org/access_use#pd-google. Please see individual items for rights and use statements |
| Subject Keyword | Temperature measurements Electron beams Nitrogen |
| Content Type | Text |
| Resource Type | Book |
