DIFFUSION, DE-EXCITATION, AND THREE-BODY COLLISION COEFFICIENTS FOR EXCITED NEON ATOMS
Diffusion coefficients, de-excitation cross sections. and three-body collision coefficienis for neon atoms or the 1s/sup 2/2s/sup 2/2p/sup 5/3s configuration are obtained from optical absorption measurements of relative decay rates and relative densities of excited atoms following a pulsed discharge. Atoms in the power metastable (/sup 3/P/sub 2/) and the lower radiating (/sup 3/P/ sub 1/) states are destroyed by diffusion to the wall, three-body collisions involving two ground state atoms, and the escape of imprisoned resonance radiation. The diffusion coefficient at unit neon density and 300 deg K for the metastable states is 5.5 x 10/sup 18/ cm/sup -1/ sec/sup -1/. The rate of escape of resonance radiation agrees with the predictions of Holstein's theory. At 300 deg K the average cross section for collisional deexcitation of /sup 3/P/ sub 1/ atoms to the /sup 3/P/sub 2/ state is 5 x 10/sup 19/ cm/sup 2/ and is about 6 x 10/sup -20/ cm/sup 2/for the /sup 3/P/sub 0/ to /sup 3/P/sub 1/ and / sup 3/P/sub 0/ too /sup 3/P/sup 2/transitions. The cross section for the /sup 3/ P/sub 1/ to /sup 3/ P/sub 2/ deexcitation increases by an order of magnitude between 200 deg K and 500 deg K and is three times larger for deexcitation by helium than by neon at 300 deg K. The threebody collision coefficient for the / sup 3/P/sub 2/ state is 5 x 10 /sup -34/ cm/sup 6/sec at 300 deg K and 5 x 10/sup -35/ cm/sup 6/sec at 77 deg K. Estimates of average cross sections for de- excitation by thermal electrons give 10/sup -13/ cm/sup 2/ for the /sup 3/P/sub 1/ to /sup 3/P /sub 2/ process and 10/sup -14/ cm/sup 2/ for the /sup 3/P/sub 0/ to /sup 3/P/sub 1/ tra nsition. (auth)
- Research Organization:
- Westinghouse Research Labs., Pittsburgh
- NSA Number:
- NSA-13-018352
- OSTI ID:
- 4230245
- Journal Information:
- Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 114; ISSN PHRVA
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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