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Doering, J. P.

Publications and source records attributed to Doering, J. P..

34 records · Page 2
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NASA NTRS1976

High resolution daytime photoelectron energy spectra from AE-E

The daytime photoelectron energy spectrum has been measured at altitudes above 154 km by the photoelectron-spectrometer experiment on the Atmosphere Explorer-E satellite. Below 200 km, well-resolved peaks are observed in the spectrum corresponding to production of O(+) and N2(+) in various electronic states from photoionization of N2 and O by solar He II (304A) radiation. Vibration-rotation excitation of N2 by inelastic electron scattering is observed at 2.5 eV. The features due to nitrogen disappear from the spectrum at altitudes above 200 km.

Doering, J. P.↗
NASA NTRS1975

Auroral electrons and the optical emissions of nitrogen

Simultaneous rocket measurements of the auroral electron flux and the optical emissions of N2 give a consistent picture of electron impact excitation in an aurora. The electron data show that the incident auroral electrons are nearly monoenergetic with energy about 25 keV. The overall shape of the observed low-energy electron spectrum is in good agreement with other recent observations and also with recent theoretical models, although there is some disagreement with the models in the value of the power law slope above 20 eV. A discussion of the secondary electron spectrum obtained near apogee shows that a single power law cannot accurately describe the secondary electron spectrum in the energy range from 3 to 85 eV. About 40% of the N2(+) 1NG (0,0) band emission at 3914 A is excited by electrons with energy below 85 eV.

Feldman, P. D.↗
NASA NTRS1973

The photoelectron-spectrometer experiment on Atmosphere Explorer.

The Atmosphere Explorer (AE) photoelectron spectrometer experiment consists of electrostatic deflection-type electron spectrometers designed to measure the low-energy electron flux expected to be encountered along the AE orbit. The system has been designed to provide general information on the intensity, angular distribution, energy spectrum, and net flows along field lines as well as sufficient energy resolution to allow the fine details of the electron-energy spectrum to be studied. The instrumentation consists of two separate electron-spectrometer detector heads connected to a common electronics system for data processing and telemetry interfacing. The experiment will measure the electron-energy spectrum from 2 to 500 eV (and possibly to less than 0.1 eV).

Doering, J. P.↗
NASA NTRS1972

High energy-resolution studies of electron impact optical excitation functions. I - The second positive system of N2.

The relative emission cross section for the N2 second positive system (0,0) and (1,0) bands excited by electron impact was measured for incident electron energies from threshold to 17 eV. The use of a high energy-resolution electron spectrometer coupled to an optical detection system made it possible to obtain the measurements with an incident electron beam having an energy half width of 50 meV. Calibration of the incident electron energy was provided by observing the scattering resonances in nitrogen and helium. The maximum of the (0,0) and (1,0) bands were found to be at approximately 14.02 and 14.3 eV, respectively. A small structural feature that was pressure-independent appeared only in the (0,0) band emission cross section. Another such feature was pressure-dependent and appeared more strongly in the (1,0) band cross section.

Finn, T. G.↗
NASA NTRS1972

Vibrational excitation of H2 by proton impact.

Measurement results are presented for the forward-scattered component of the absolute cross sections pertaining to proton- and deuteron-impact excitation of the first four vibrational levels of the electronic ground state of H2. The significance and implications of these results are discussed.

Herrero, F. A.↗