The effect of viewing angle on the spectral behavior of a Gd plasma source near 6.7 nm

Journal Article · Mon Apr 02 00:00:00 EDT 2012 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3701593· OSTI ID:22025496

O'Gorman, Colm; Bowen, Li; Cummins, Thomas; Dunne, Padraig; Sokell, Emma; O'Sullivan, Gerry ^[1]; Otsuka, Takamitsu ^[2]; Yugami, Noboru; Higashiguchi, Takeshi ^[2]; Weihua, Jiang ^[3]; Endo, Akira ^[4]

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1. School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)
2. Department of Advanced Interdisciplinary Sciences, Center for Optical Research and Education (CORE), and Optical Technology Innovation Center (OpTIC), Utsunomiya University, Yoto 7-1-2, Utsunomiya, Tochigi 321-8585 (Japan)
3. Department of Electrical Engineering, Nagaoka University of Technology, Kami-tomiokamachi 1603-1, Nagaoka, Niigata 940-2188 (Japan)
4. Research Institute for Science and Engineering, Waseda University, Okubo 3-4-1, Shinjuku, Tokyo 169-8555 (Japan)

We have demonstrated the effect of viewing angle on the extreme ultraviolet (EUV) emission spectra of gadolinium (Gd) near 6.7 nm. The spectra are shown to have a strong dependence on viewing angle when produced with a laser pulse duration of 10 ns, which may be attributed to absorption by low ion stages of Gd and an angular variation in the ion distribution. Absorption effects are less pronounced at a 150-ps pulse duration due to reduced opacity resulting from plasma expansion. Thus for evaluating source intensity, it is necessary to allow for variation with both viewing angle and target orientation.

• OSTI ID: 22025496
• Journal Information: Applied Physics Letters, Vol. 100, Issue 14; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ABSORPTION
ANGULAR DISTRIBUTION
EMISSION SPECTRA
EXTREME ULTRAVIOLET RADIATION
GADOLINIUM
GADOLINIUM IONS
LASER TARGETS
LASER-PRODUCED PLASMA
LASERS
OPACITY
PLASMA EXPANSION
PLASMA PRODUCTION
PULSES
VARIATIONS