Plasma x-ray emission produced by ruby lasers at 10/sup 1/2 W/cm/sup 2/

Journal Article · Sat Jul 01 04:00:00 EDT 1978 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.325387· OSTI ID:6775486

Bleach, R D; Nagel, D J

Q-switched 20-nsec ruby-laser pulses (approx.0.5 GW) were focused to about 10/sup 1/2 W/cm/sup 2/ on targets containing elements in the range 6< or =Z< or =68. Time- and space-integrated x-ray emission from plasmas 200 ..mu..m in diameter with lifetimes near 12 nsec was measured with four active detectors at energies between 0.1 and 5 keV. Maxima in x-ray intensity measured by each detector occurred when binding energies of core electrons in target atoms were 20--30 times the electron plasma temperature. Calculated detector response functions together with coronal-model plasma emission computations were used to analyze the atomic-number dependence of the detector signals. A plasma electron temperature of 70 eV and an electron density of about 4 x 10/sup 2/0 cm/sup -/3 gave the best fit to the ratios of signals. Computed spectra for this temperature showed that the peaks in the low-energy detector (an x-ray diode most sensitive near 0.15 keV) were due in part to line radiation. Peaks in the three detectors sensitive above 1 keV (two silicon PIN diodes and an ionization chamber) were primarily due to recombination radiation. The results of this work augment an earlier similar, but limited, study at 10/sup 1/2 W/cm/sup 2/.

• Research Organization: Naval Research Laboratory, Washington, D.C. 20375
• OSTI ID: 6775486
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 49:7; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
ELECTRON DENSITY
ELECTRON TEMPERATURE
EMISSION SPECTRA
FOCUSING
LASER-PRODUCED PLASMA
LASERS
PLASMA
PLASMA DIAGNOSTICS
Q-SWITCHING
RUBY LASERS
SOLID STATE LASERS
SPECTRA
X-RAY SPECTRA