Self-contraction process and hot spot formation in the SHOTGUN III-U divergent gas-puff Z pinch

Takasugi Keiichi; Nishio Mineyuki

doi:10.1063/1.5133007

Volume 5 Issue 4

Jul. 2020

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Takasugi Keiichi, Nishio Mineyuki. Self-contraction process and hot spot formation in the SHOTGUN III-U divergent gas-puff Z pinch[J]. Matter and Radiation at Extremes, 2020, 5(4): 047401. doi: 10.1063/1.5133007

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Takasugi Keiichi, Nishio Mineyuki. Self-contraction process and hot spot formation in the SHOTGUN III-U divergent gas-puff Z pinch[J]. Matter and Radiation at Extremes, 2020, 5(4): 047401. doi: 10.1063/1.5133007

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Self-contraction process and hot spot formation in the SHOTGUN III-U divergent gas-puff Z pinch

doi: 10.1063/1.5133007

Takasugi Keiichi^{1
,
,
,},
Nishio Mineyuki²

1.
Institute of Quantum Science, Nihon University, Tokyo 101-8308, Japan
2.
Anan College, National Institute of Technology, Tokushima 774-0017, Japan

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Corresponding author: a)Author to whom correspondence should be addressed: takasugi@phys.cst.nihon-u.ac.jp
Received Date: 2019-10-24
Accepted Date: 2020-04-12

Available Online: 2020-07-01

Publish Date: 2020-07-15

Abstract

Abstract

A divergent gas-puff Z pinch has been devised for the realization of an efficient soft x-ray point source. In this device, a divergent hollow annular gas puff is ejected outward from the surface of the inner electrode, and the plasma is compressed three-dimensionally to generate a soft x-ray point source. In the SHOTGUN III-U device at Nihon University, the power supply was enhanced, and experiments were conducted over a larger current range. The peak current at the charging voltage of −25 kV was −190 kA. Ar was used as the discharge gas. The self-contraction process of the plasma was investigated in detail using a gated camera. Near the peak current, local contraction occurred in front of the inner electrode. The contraction velocity of the plasma was 5.5 × 10⁴ m/s. As the plasma contracted, the discharge current decreased. The energy input was analyzed by induction acceleration. The net input energy was found to be 750 J, which corresponded to 13.3% of the stored energy of the capacitor, 5630 J. The soft x-ray source was observed using a soft x-ray CCD camera. A point source was observed 7 mm in front of the inner electrode. The size of the source was 35 µm in the axial direction and 14 µm in the radial direction.

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References(16)

References

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