Efficient electron beam deposition in the gas cell of the Electra laser

Extensive research has been performed to elucidate the transport of electron beam energy from a vacuum diode, through a foil support structure (hibachi), and into the Electra laser cell. Measurements and simulations of the energy deposition in the cell are reported for various krypton/argon mixtures, gas pressures, and the thickness and material of the hibachi foil. Two hibachi and several cathode configurations are investigated and electron energy deposition efficiencies into the gas of up to 75% have been achieved with a 500 kV, 180 ns full width at half maximum diode pulse. The experimental data are compared with one-, two-, and three-dimensional Monte Carlo transport calculations and particle-in-cell simulations. The importance of electron backscattering, radiation effects, and power deposition uniformity in the laser gas are discussed.

[1]  Edward T. Salesky,et al.  KrF Laser Studies at High Krypton Density , 1987 .

[2]  M. Shaw,et al.  A single-mode KrF laser , 1987 .

[3]  John Giuliani,et al.  Development of Electron Beam Pumped KrF Lasers for Fusion Energy , 2002 .

[4]  E. Salesky,et al.  Electron-beam pumped KrF laser extraction measurements for high Kr concentration gas mixtures , 1985 .

[5]  B. G. Logan,et al.  The US inertial confinement fusion (ICF) ignition programme and the inertial fusion energy (IFE) programme , 2003 .

[6]  D. Klimek,et al.  Kinetic issues for short-pulse KrF laser operation , 1981 .

[7]  A. Mandl,et al.  Electron beam deposition studies of the rare gases , 1986 .

[8]  Moshe Friedman,et al.  Reduction of edge emission in electron beam diodes , 2002 .

[9]  Susumu Kato,et al.  Electron-beam-pumped high-repetition-rate KrF laser system , 2000, Advanced High-Power Lasers and Applications.

[10]  S. P. Obenschain,et al.  A rep rate KrF system to address issues relevant to inertial fusion energy , 1999 .

[11]  Fumihiko Kannari,et al.  Parametric studies of an electron‐beam‐pumped krypton‐rich KrF laser , 1987 .

[12]  D. V. Rose,et al.  Numerical modeling of large-area electron-beam diodes for KrF lasers , 2003 .

[13]  John Giuliani,et al.  Electra: Repetitively pulsed, 500 J, 100 ns, KrF oscillator , 2004 .

[14]  Minoru Obara,et al.  Power extraction study of an e-beam-pumped atmospheric pressure, Kr-rich KrF laser amplifier , 1989 .

[15]  I. D. Smith,et al.  Large area electron beam pumped krypton fluoride laser amplifier , 1997 .

[16]  I. D. Smith,et al.  Pulsed power for a rep-rate, electron beam pumped KrF laser , 2000 .

[17]  John Robinson Pierce,et al.  Theory and Design of Electron Beams , 1954 .

[18]  Paul C. Kepple,et al.  Electron beam pumped krypton fluoride lasers for fusion energy , 2004, Proceedings of the IEEE.

[19]  Manfred Salvermoser,et al.  LASERS IN DENSE GASES PUMPED BY LOW-ENERGY ELECTRON BEAMS , 1998 .

[20]  Martin J. Berger,et al.  Tables of energy losses and ranges of electrons and positrons , 1964 .

[21]  Wayne R. Meier,et al.  Fusion energy with lasers, direct drive targets, and dry wall chambers , 2003 .

[22]  V. Kuznetsov,et al.  Numerical investigations of electron beam energy deposition into the gas medium of an excimer laser , 1991 .

[23]  M. Shaw,et al.  60‐ns E‐beam excitation of rare‐gas halide lasers , 1980 .

[24]  Hidehiko Yashiro,et al.  Performance of the `Super-ASHURA' main amplifier , 1999 .

[25]  G. D. Valdez,et al.  ITS: the integrated TIGER series of electron/photon transport codes-Version 3.0 , 1991, Conference Record of the 1991 IEEE Nuclear Science Symposium and Medical Imaging Conference.

[26]  Robert Fedosejevs,et al.  Measurements of gain and absorption saturation in an electron-beam-pumped KrF amplifier , 1989 .

[27]  Louis A. Rosocha,et al.  Electron-Beam Sources for Pumping Large Aperture KrF Lasers , 1987 .

[28]  C. Duzy,et al.  A study of VUV fluorescence and lasing in electron beam excited xenon , 1980, IEEE Journal of Quantum Electronics.

[29]  A. Kantz,et al.  Dosimetry and Quality Control in Electron Beam Processing , 1979, IEEE Transactions on Nuclear Science.

[30]  Susumu Kato,et al.  Initial testing of a high-repetition-rate electron-beam-pumped KrF laser amplifier , 2001 .

[31]  Wayne R. Meier,et al.  Osiris and SOMBRERO inertial fusion power plant designs–summary, conclusions, and recommendations , 1994 .

[32]  F. Kannari,et al.  Energy deposition measurements of a large‐diameter, intense relativistic electron beam for high‐power gas laser excitation , 1984 .

[33]  M. Rokni,et al.  Pulse shape and laser-energy extraction from e-beam-pumped KrF/asterisk/ , 1979 .

[34]  M. Obara,et al.  Atmospheric Pressure Operation of a KrF Laser Oscillator and Amplifier with a Krypton-Rich Mixture and a Kr/F 2 Mixture , 1987 .

[35]  Vladimir D. Zvorykin,et al.  Transport of electron beams and stability of optical windows in high-power e-beam-pumped krypton fluoride lasers , 2001 .

[36]  Louis A. Rosocha,et al.  Aurora multikilojoule KrF laser system prototype for inertial confinement fusion , 1987 .