Relation between solar and planetary neon in carbonaceous chondrites.
Explore the source record for details and available documents.
SEARCH · Engineering Papers
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Excitation of the 4d and 5p levels of Zn+ by charge exchange bewteen Ne+ and Zn was investigated. From measured electron temperature and line intensity ratios it was concluded that charge exchange is the dominate mechanism for populating the 4d2D5/2 level of Zn+. Comparison of Zn-Ne and Zn-Ar results imply the same conclusion. No evidence for charge exchange as the dominant pumping mechanism for the 5p2Pl/2, 5p2P3/2, or 4d2D3/2 levels was obtained.
Explore the source record for details and available documents.
Excitation of the 4d and 5p levels of Zn(+) by charge exchange between Ne(+) and Zn was investigated. From measured electron temperature and line intensity ratios it was concluded that charge exchange is the dominant mechanism for populating the 4d 2D5/2 level of Zn(+). Comparison of Zn-Ne and Zn-Ar results imply the same conclusion. No evidence for charge exchange as the dominant pumping mechanism for the 5p 2P1/2, 5p 2P3/2, or 4d 2D3/2 levels was obtained.
Explore the source record for details and available documents.
X-ray energies, Auger and radiative decay rates, and fluorescence yields have been computed in intermediate coupling for the various states of the 1s2s3s, 1s2s3p, 1s2p3p, 1s2p3s, and 1s2p3d configurations of Ne-10(7+). The results supplement recent experimental work on these transitions.
In order to determine the physical processes for pumping this laser, a detailed study of the afterglow system has been performed. The pumping mechanism has been found to be collisional-radiative electron-ion recombination. Microwave quenching of both the laser and spontaneous afterglow light have shown conclusively that a recombination process directly produces a nitrogen atom in either the upper laser level or, more likely, in a higher lying energy level which rapidly de-excites to the upper laser level.
Explore the source record for details and available documents.
Results of detailed and systematic calculations are presented for the total dielectronic recombination rate coefficients for the ions of Ne, Mg, and S in a low-density predominantly hydrogen plasma. The new recombination rates are used to calculate solar corona ionization-equilibrium distributions of the ions. The most important effect of dielectronic recombination for ions in corona equilibrium is found to be a shift in the maximum-abundance temperatures toward higher temperatures, which are in some cases reduced from those predicted on the basis of the simple Burgess formula.
A Ne-E rich phase was separated from the Orgeuil carbonaceous chondrite. He and Ne were analyzed in this phase and in an Orgueil residual bulk silicate sample using the stepwise heating technique. Ne-E was found to be released from the Ne-E rich phase at temperatures as low as 500 C; however, gas richest in Ne-E is observed at the highest temperatures (1230 C). The following limits for the isotopic composition of Ne-E were obtained: Ne-20/Ne-22 less than 1.52; Ne-21/Ne-22 less than 0.0244.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Airborne measurements of the Ar II (6.99 micron) and S III (18.71 micron) forbidden lines for six compact H II regions are presented, as well as ground-based 2-4 micron and 8-13 micron spectroscopy if not already published. From these data and radio data, lower limits to the elemental abundances of Ar, Ne, and S are deduced. G29.9-0.0, at 5 kpc from the galactic center, is overabundant in all these elements. The other five regions (at distances 6-13 kpc from the center) mainly appear to be consistent with standard abundances, with the exception of G75.84 + 0.4 at 10 kpc from the galactic center, which is overabundant in S. However, preliminary results on G12.8-0.2 at 6 kpc from the galactic center suggest a possible underabundance. A large statistical sample of H II regions is required in order to determine if there is a radial gradient in the heavy element abundances of the Galaxy.