Specific features of the structure of the Z-pinch emitting region formed during the implosion of a foam-wire load at the ANGARA-5-1 facility

Journal Article · Tue Jan 15 00:00:00 EST 2013 · Plasma Physics Reports

DOI:https://doi.org/10.1134/S1063780X12120045· OSTI ID:22163095

Grabovski, E. V.; Gritsuk, A. N.; Laukhin, Ya. N.; Aleksandrov, V. V.; Oleinik, G. M.; Medovshchikov, S. F. ^[1]; Shevel'ko, A. P. ^[2]

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1. Troitsk Institute for Innovation and Fusion Research (Russian Federation)
2. Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

Results are presented from experimental studies of the structure of the compressed plasma of a Z-pinch produced during the implosion of a foam-wire load at the current of up to 3 MA. The foam-wire load consisted of two nested cylindrical cascades, one of which was a solid or hollow cylinder made of low-density agar-agar foam, while the other was a wire array. The wall thickness of a hollow foam cylinder was 100-200 {mu}m. The images of the pinch and its spectrum obtained with the help of multiframe X-ray cameras and a grazing incidence spectrograph with a spatial resolution were analyzed. Data on the spatial structure of the emitting regions and the soft X-ray (SXR) spectrum of the Z-pinch in the final stage of compression of a foam-wire load were obtained. The implosion modes characterized by the formation of hot regions during implosion of such loads were revealed. The characteristic scale lengths of the hot regions were determined. It is shown that the energy distribution of SXR photons in the energy range from 80 eV to 1 keV forms the spatial structure of Z-pinch images recorded during the implosion of foam-wire loads. It is revealed that the spectral density of SXR emission in the photon energy range of 300-600 eV from hot Z-pinch regions exceeds the spectral density of radiation from the neighboring Z-pinch regions by more than one order of magnitude. Groups of lines related to the absorption and emission of radiation by atoms and multicharged ions of carbon and oxygen in the outer foam cascade of a foam-wire load were recorded for the first time by analyzing the spatial distribution of the SXR spectra of multicharged ions of the Z-pinch. The groups of absorption lines of ions (C III, O III, O IV, and O VI) corresponding to absorption of SXR photons in the Z-pinch of a tungsten wire array, which served as the inner cascade of a foam-wire load, were identified. The plasma electron temperature measured from the charge composition of carbon and oxygen ions in the outer agar-agar foam cascade was 10-40 eV. During the implosion of foam-wire loads at currents of up to 3 MA, SXR pulses (h{nu} > 100 eV) with a duration of 10 ns and peak power of 3 TW were detected. It is shown that the temporal profile of single-peak and double-peak SXR pulses can be controlled by varying the parameters of the outer and inner cascades of the foam-wire load.

• OSTI ID: 22163095
• Journal Information: Plasma Physics Reports, Vol. 39, Issue 1; Other Information: Copyright (c) 2013 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-780X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ABSORPTION
CAMERAS
CYLINDRICAL CONFIGURATION
ELECTRIC CURRENTS
ELECTRON TEMPERATURE
EV RANGE 100-1000
FOAMS
IMPLOSIONS
MULTICHARGED IONS
OXYGEN
OXYGEN IONS
PHOTONS
PLASMA
SOFT X RADIATION
SPATIAL DISTRIBUTION
SPATIAL RESOLUTION
SPECTRAL DENSITY
TUNGSTEN
VISIBLE SPECTRA
WIRES