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Rotational Raman scattering on the vibrational ground state of CO 2 was performed to determine the gas temperature in narrow-gap dielectric barrier discharges (DBDs). The Raman spectrometer was equipped with a straightforward spectral filtering to mask ca. 30 cm −1 (0.85 nm) centered around the excitation wavelength of 532 nm. Linearisation of the observed transitions ( J = 18–42) was applied to retrieve gas temperatures in discharge gaps of 1 mm. The DBD was operated in pure CO 2 at atmospheric pressure and non-negligible gas heating of about 160 K was observed at 33 W injected power. Based on a simplified energy balance the gas temperature measurements were extrapolated to a broad range of injected plasma power values (0–60 W).

In this paper we report on the generation of high transient heat and particle fluxes in Pilot-PSI. A capacitor bank (8400 mu F, 37.8 kJ) is coupled to the plasma source to superimpose the pulsed plasma on the top of steady-state plasma beam. Discharge currents up to 11.6 kA were reached corresponding to an input power in the source of 4.5 MW. By varying the discharge current and the gas flow, electron density and temperature during the pulse were varied in the range 40-120 x 10(20) m(-3), and 2-6 eV, respectively. The current rise time is about 300-500 mu s while the pulse duration is 1-1.5 ms. Thermal response of a tungsten target was monitored by fast infrared camera. The temperature rise time is about 0.5 ms and the heat flux to the target was up to 1 GW/m(2). (C) 2010 Elsevier B.V. All rights reserved.

The FOM-Institute for Plasma Physics Rijnhuizen is constructing Magnum-PSI; a magnetized (3 T), steady-state, large area (80 cm2) high-flux (up to 1 024 H+ ions m-2 s-1) plasma generator. Magnum-PSI will be a highly accessible laboratory experiment in which the interaction of magnetized plasma with different surfaces can be studied. This experiment will provide new insights in the complex physics and chemistry that will occur in the divertor region of the future experimental fusion reactor ITER. Here, extremely high power and particle flux densities are predicted at relatively low plasma temperatures. Magnum-PSI will be able to simulate these detached ITER divertor conditions in detail. In addition, conditions can be varied over a wide range, such as different target materials, plasma temperatures, beam diameters, particle fluxes, inclination angles of target, background pressures, magnetic fields, etc., making Magnum-PSI an excellent test bed for high heat flux components of future fusion reactors. The design phase of the Magnum-PSI device has been completed. The construction and assembly phase of the device is in progress. In this contribution, we will present the design and construction of the Magnum-PSI experiment. The status of the vacuum system, the 3 T superconducting magnet, the plasma source, the target plate and manipulator, and additional plasma heating will be presented. The plasma and surface diagnostics that will be used in the Magnum-PSI experiment will be introduced. © 2010.

We report on the generation of high transient heat and particle fluxes in a linear plasma device by pulsed operation of the plasma source. A capacitor bank is discharged into the source to transiently increase the discharge current up to 1.7 kA, allowing peak densities and temperature of 70x10(20) m(-3) and 6 eV corresponding to a surface power density of about 400 MW m(-2). (C) 2010 American Institute of Physics. [doi: 10.1063/1.3484961]

A highly sensitive imaging Thomson scattering system was developed for low temperature (0.1-10 eV) plasma applications at the Pilot-PSI linear plasma generator. The essential parts of the diagnostic are a neodymium doped yttrium aluminum garnet laser operating at the second harmonic (532 nm), a laser beam line with a unique stray light suppression system and a detection branch consisting of a Littrow spectrometer equipped with an efficient detector based on a "Generation III" image intensifier combined with an intensified charged coupled device camera. The system is capable of measuring electron density and temperature profiles of a plasma column of 30 mm in diameter with a spatial resolution of 0.6 mm and an observational error of 3% in the electron density (n(e)) and 6% in the electron temperature (T-e) at n(e)=4 x 10(19) m(-3). This is achievable at an accumulated laser input energy of 11 J (from 30 laser pulses at 10 Hz repetition frequency). The stray light contribution is below 9 x 10(17) m(-3) in electron density equivalents by the application of a unique stray light suppression system. The amount of laser energy that is required for a n(e) and T-e measurement is 7 x 10(20)/n(e) J, which means that single shot measurements are possible for n(e)>2 x 10(21) m(-3). (C) 2008 American Institute of Physics.