SPECTRA INDUCED BY 200-Kev PROTON IMPACT ON HELIUM
Spectra induced by 200-kev proton impact on helium was observed in the spectral region of lambda 3500 A to lambda 6000 A. /sup 1/S states appear to be strongly excited. Absolute crosssections for the direct excitation of the 4 /sup 1/S and 5 /sup 1/S states of neutral helium were determined as well as the simultaneous ionization and excitation cross-section for helium into the n = 4 state of He/sup +/. Of the more intense lines, only the 2 /sup 1/P-n /sup 1/S lines and the He II lambda 4686 line behaved linearly with pressure within experimental error. Triplet spectra were observed in which the dominant feature was the 2/sup 3/Pn /sup 3/D lines. The populations of the 4 /sup 3/D and 4 /sup 1/D states, in particular, were analyzed as a function of a direct mechanism and collision of the second kind which seem to fit the data fairly well. A very weak Doppler-shifted H/sub i line was detected. If this is interpreted to be produced by charge exchange, then the cross section for electron capture into the n = 4 state of hydrogen is estimated to be of the order of 8 x 10/sup -21/ cm/sup 2/. (auth)
- Research Organization:
- Univ. of Arkansas, Fayetteville
- NSA Number:
- NSA-15-016244
- OSTI ID:
- 4031329
- 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- Physical Review (U.S.) Superseded in part by Phys.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 D, Journal Name: Physical Review (U.S.) Superseded in part by Phys.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: 122; ISSN PHRVA
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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EXCITATION OF Ne, Ar, AND Kr INDUCED BY H$sup +$ AND He$sup +$ IMPACT (5-35 kev)