Radiance line ratios Ly-β/Ly-α, Ly-γ/Ly-α, Ly-δ/Ly-α, and Ly-ε/Ly-α for soft X-ray emissions following charge exchange between C6+ and Kr

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:350

Article

Andrianarijaona, V. M.¹  Wulf, D.²  McCammon, D.²  Seely, D. G.³  Havener, C. C.⁴ 

[1] Pacific Union Coll, Dept Phys, Angwin, CA 94508 USA

[2] Univ Wisconsin, Dept Phys, Madison, WI 53706 USA

[3] Albion Coll, Dept Phys, Albion, MI 49224 USA

[4] Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA

关键词: Ion-atom collision;    Charge transfer;    Soft X-ray;    Solar wind;    Comet dusts;   

DOI  :  10.1016/j.nimb.2015.01.040

来源: Elsevier

【 摘 要 】

The radiance line ratios Ly-beta/Ly-alpha, Ly-gamma/Ly-alpha, Ly-delta/Ly-alpha, and Ly-epsilon/Ly-alpha for soft X-ray emission following charge exchange (CX) between C6+ and Kr are reported for collision energies between approximately 320 and 46,000 eV/u. The corresponding collision velocities (250-3000 km/s) are characteristic of the solar wind. X-ray spectra were obtained at the Oak Ridge National Laboratory Multicharged Ion Research Facility using a microcalorimeter X-ray detector with a resolution on the order of 10 eV FWHM. The measured Ly-beta/Ly-alpha is zero for all considered energies and suggests that very little, if any, capture to 6p occurs. The measured Ly-beta/Ly-alpha and Ly-gamma/Ly-alpha ratios intersect and form a well resolved node around (950 +/- 50) km/s, which could be used as an astrophysical velocity indicative tool. The results reported here are compared to calculations for C6+ + H since no published theory for C6+ + Kr is known to exist. Double-electron-capture (DEC) and other multi-electron processes are possible. True double capture is estimated to be only 10% of the single-electron-capture (SEC). (C) 2015 Published by Elsevier B.V.

【 授权许可】

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