Title :
Diagnostics of small plasma focus device at CTU in prague
Author :
Kravarik, J. ; Kubes, P. ; Klir, D. ; Rezac, K.
Author_Institution :
CTU, Prague, Czech Republic
Abstract :
Summary form only given. The plasma focus (PF) devices are simple sources of neutrons produced by fusion d(D,n)3He reaction. The device at CTU is equipped with the Mather type of electrodes. The diameter and the length of the copper anode are 2.7 cm and 11 cm, respectively. The cathode is formed from 12 steel rods, each of 6 mm in diameter and 19 cm in length. The diameter of the cathode cylindrical configuration is 6 cm. The copper cylindrical anti-anode has the diameter of 2.7 cm and the distance between the anode and anti-anode is 1 cm. Total energy of the capacitor bank of 3 kJ is obtained at the charging voltage of 15 kV. The maximum of the current of 180kA is reached within 1.8 ??s. The initial pressure of deuterium in the discharge chamber was 700 ? 900 Pa. The x-ray and neutron diagnostics was used. Soft X-rays were registered with the silicon PIN detector filtered with an Al 1.5 ??m foil, four quadrants MCP detector in the photon energy range above 10 eV, 2 ns exposure time, and time integrated XUV spectrometer. Fast plastic scintillation detectors of 5 cm thickness equipped with the photo- multipliers Hamamatsu Rl 828-01 enabled a time resolved measurement of neutron emission and hard X-rays above lOOkeV. The time delay between the current onset and the pinch phase, when x-rays and neutrons were generated, varied in the range of 1.8 ? 2.2 ??s. The pinch phase was characterized by the deep of the current derivative. The minimum of the deep of the current derivative was chosen as the time zero. The electrode configuration with anti-anode (PF-Z-pinch) allows a gene-ration the short (shorter than 10 ns) hard x-ray and neutron pulses. This fact enables to study the temporal correlation of the hard x-ray with neutron production and as well the neutron production.
Keywords :
discharges (electric); pinch effect; plasma diagnostics; plasma focus; cathode cylindrical configuration; copper cylindrical anti-anode; discharge chamber; electrodes; fast plastic scintillation detectors; hard X-ray; neutron production; photo- multipliers; pinch phase; plasma diagnostics; plasma focus device; soft X-rays; Anodes; Cathodes; Copper; Electrodes; Neutrons; Plasma devices; Plasma diagnostics; Plasma sources; X-ray detection; X-ray detectors;
Conference_Titel :
Plasma Science - Abstracts, 2009. ICOPS 2009. IEEE International Conference on
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4244-2617-1
DOI :
10.1109/PLASMA.2009.5227523