K-shell emission trends from 60 to 130 cm/ μ s stainless steel implosions

• Published in: Physics of plasmas 2013-10, Vol.20 (10)
• Main Authors: Ampleford, D. J., Jennings, C. A., Jones, B., Hansen, S. B., Cuneo, M. E., Coverdale, C. A., Jones, M. C., Flanagan, T. M., Savage, M., Stygar, W. A., Lopez, M. R., Apruzese, J. P., Thornhill, J. W., Giuliani, J. L., Maron, Y.
• Format: Article
• Language: English
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELECTRON TEMPERATURE; EXPLODING WIRES; IMPLOSIONS; ION TEMPERATURE; K SHELL; KEV RANGE; PHOTONS; PINCH EFFECT; PLASMA DENSITY; SOFT X RADIATION; STAINLESS STEELS; X-RAY SOURCES
• ISSN: 1070-664X; 1089-7674
• DOI: 10.1063/1.4823711

Recent experiments at the 20 MA Z Accelerator have demonstrated, for the first time, implosion velocities up to 110–130 cm/μs in imploding stainless steel wire arrays. These velocities, the largest inferred in a magnetically driven implosion, lead to ion densities of 2 × 1020 cm−3 with electron temperatures of ∼5 keV. These plasma conditions have resulted in significant increases in the K-shell radiated output of 5–10 keV photons, radiating powers of >30 TW and yields >80 kJ, making it the brightest laboratory x-ray source in this spectral region. These values represent a doubling of the peak power and a 30% increase in the yield relative to previous studies. The experiments also included wire arrays with slower implosions, which were observed to have lower temperatures and reduced K-shell output. These colder pinches, however, radiated 260 TW in the soft x-ray region, making them one of the brightest soft x-ray sources available.