Laser intensities of order and above 0.001 times the relativistic intensity Irel coupled with ionized target electron number densities close to and above the laser cutoff density nec exhibit sudden relativistic self-focusing, with attendent beam converging lengths about equal to the diameter of the initial vacuum laser beam. The analytical model is a relativistic generalization, including mass and energy effects, of the plasma electron-ion collision process, combined with a local bending of the laser beam wave front resulting from influences on the plasma refractive index. Dependences on the plasma temperature, degree of ionization and instabilities, as given by an effective collision frequency, are studied. Self-focusing and dielectric swelling results in maximum oscillation energies in agreement with several high intensity experiments. The wavelength independence of electron energy, as shown in the recent experiments of G. H. McCall, as well as measured MeV ion emission from irradiated targets, can be explained by the model. It is concluded that Nd glass laser beams of 1014 Watts power will generate dense plasmas containing highly charged heavy ions with maximum energies approximately 20 GeV.
KeywordsLaser Intensity Electron Number Density Oscillation Energy Glass Laser Effective Collision Frequency
Unable to display preview. Download preview PDF.
- 3.E. L. Kane and H. Hora, submitted to Aust. J. Phys.Google Scholar
- 4.E. L. Kane and H. Hora, Conference on Lasers and Nonlinear Optics, Tbilissi, May, 1976; R. Castillo, et al., Nucl Inst. and Methods (in print).Google Scholar
- 7.G. H. McCall, Conference on Lasers and Nonlinear Optics, Tbilissi, May, 1976.Google Scholar
- 8.H. Hora and E. L. Kane, to be published in Appl. Phys. (1977).Google Scholar
- 10.M. S. Sodha, A. K. Ghatak and V. K. Tripathi, Progress in Optics XIII, Ed. E. Wolf, p. 171, (1976).Google Scholar
- 15a.F. F. Chen in Laser Interaction and Related Plasma Phenomena, H. Schwarz and H. Hora, eds. (Plenum, New York, 1974) Vol. 3A, p.291.Google Scholar
- 17.H. Hora, Laser Interaction and Related Plasma Phenomena, H. Schwarz and H. Hora, eds. (Plenum, New York, 1974) Vol. 3B, p. 819.Google Scholar
- 19.R. E. Kidder in Proc. of International School of Physics “Enrico Fermi”, Physics of High Energy Density, P. Caldirola and H. Knoepfel, eds. (Academic Press, 1971) Vol. XLVIII, p. 306.Google Scholar
- 21.L. Spitzer, jr., Physics of Fully Ionized Gases, (Interscience, New York, 1962).Google Scholar
- 22a.T. W. Johnston and J. Dawson, Phys. Fluids 16, 722 (1973).Google Scholar