Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-28T00:40:25.817Z Has data issue: false hasContentIssue false
  • English
  • Français

Doppler-shift decoupling of radiation reabsorption in expanding laser-produced plasmas

Published online by Cambridge University Press:  09 March 2009

W. Brunner  and
R. W. John
W. Brunner
Affiliation:
Zentralinstitut f¨r Optik und Spektroskopie, Rudower Chaussee 6, 0–1199 Berlin, Germany
R. W. John
Affiliation:
Zentralinstitut f¨r Optik und Spektroskopie, Rudower Chaussee 6, 0–1199 Berlin, Germany
Get access Rights & Permissions [Opens in a new window]

Abstract

To investigate the influence of radiation reabsorption on the level populations of ions in an expanding laser-produced plasma of intermediate density, we start with the system of rate equations for the population densities coupled with the line-radiation transport equation, the dynamical Doppler effect due to the differential macroscopic velocity field included. In a physically motivated approximation, for spatially varying absorption and emission, and general three-dimensional plasma geometry, an integral equation describing the effect of Lyman-a radiation reabsorption on the spatial behavior of the population density of the upper resonance level is derived. Assuming a sufficiently large velocity gradient so that the Doppler-induced frequency shift dominates the linewidth, after asymptotically evaluating the frequency integral involved in the kernel we are led to a simplified integral equation exhibiting the reduction of radiation reabsorption by Doppler decoupling. In particular, in the case of a cylindrical, radially expanding laser plasma we discuss this Fredholm equation for the reabsorption-influenced population density.

Type
Research Article
Information
Laser and Particle Beams , Volume 9 , Issue 4 , December 1991 , pp. 817 - 828
Copyright
Copyright © Cambridge University Press 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Apruzese, J. P. et al. 1986 J. Phys. 47, C6–15.Google Scholar
Borovsky, A. V., Korobkin, V. V. & Mukhtarov, Ch. K. 1985 IOFAN Preprint No. 21, Moscow.Google Scholar
Brunner, W. & John, R. W. 1989 In Abstracts of the 2nd European Conference on Quantum Electronics (EQEC '89), Dresden, Junge, K., Brunner, W. & Paul, H., volume eds. Europhysics Conference Abstracts 13D [European Physical Society], series editor, K. Bethge), Part II, Poster No. 2.6.Google Scholar
Brunner, W. & Schlegel, Th. 1988 Laser Part. Beams 6, 277.CrossRefGoogle Scholar
Brunner, W. et al. 1988 Laser Part. Beams 6, 723.CrossRefGoogle Scholar
Chenais-Popovics, C. et al. 1987 Phys. Rev. Lett. 59, 2161.Google Scholar
Derzhiev, V. I., Zhidkov, A. G. & Yakovlenko, S. I. 1986 Radiation of Ions in a Non-Equilibrium Dense Plasma (Energoatomizdat, Moscow) (in Russian).Google Scholar
Derzhiev, V. I. et al. 1987 J. Phys. B 20, 6165.Google Scholar
Eder, D. C. et al. 1987 J. Opt. Soc. Am. B 4, 1949.CrossRefGoogle Scholar
Mikhlin, S. G. 1957 Integral Equations (Pergamon, London).CrossRefGoogle Scholar
Nam, C. H. et al. 1986 J. Opt. Soc. Am. B 3, 1199.Google Scholar
Paul, H. 1988 Private communication.Google Scholar
Rybicki, G. B. 1970 In Spectrum Formation in Stars with Steady-State Extended Atmospheres, NBS Spec. Publ. No. 332, Groth, H. & Wellmann, P., eds. (U.S. GPO, Washington, DC), p. 87.Google Scholar
Rybicki, G. B. 1984 In Methods in Radiative Transfer, Kalkofen, W., ed. (Cambridge Univ. Press, Cambridge), p. 21.Google Scholar
Shestakov, A. I. & Eder, D. C. 1989 J. Quant. Spectrosc. Radiat. Transfer 42, 483.CrossRefGoogle Scholar
Sobolev, V. V. 1957 Astron. Zh. 34, 694.Google Scholar
Sobolev, V. V. 1985 A Course in Theoretical Astrophysics, 3rd ed. (Nauka, Moscow) (in Russian).Google Scholar
Whitten, B. L., London, R. A., & Walling, R. S. 1988 J. Opt. Soc. Am. B 5, 2537.CrossRefGoogle Scholar