TITLE:
Variation of Radiation Emission with Argon Gas Pressure in UM Plasma Focus with the Hollow Anode
AUTHORS:
Muhammad Zubair Khan, Yap Seong Ling, Wong Chiow San
KEYWORDS:
Plasma Focus; UM Plasma Focus; Radiation Emission; Electron Temperature; X-Ray Yield; Instabilities
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.3 No.2,
June
20,
2013
ABSTRACT: A Plasma Focus device (2.2 kJ, 12 kV) is studied as a pulsed X-ray
source, operated with Argon at a filling pressure in the range of 0.7 to 2.5
mbar. The time resolved X-ray signals are measured with an array of PIN diode
detectors. The X-ray emission produced by the plasma focus discharge at various
pressures is investigated and compared. It is found that at the high pressure
regime of more than 1.5 mbar, very consistent and high output of X-ray
radiation is obtained, at the peak of the discharge current. A remarkable
increase of about five times of the average X-ray yield is achieved at optimum
pressure 1.7 mbar compared to that obtained at other pressures. An indirect
method to determine the electron temperature of the plasma is achieved by using
the array of 5 channel PIN diode detector coupled with Al foil of different
thicknesses. The result shows that the electron temperature of the plasma is 7
keV, when the operating pressure is at 1.7 mbar. The maximum total X-ray yield
is about 2.53 mJ per shot at optimum pressure, equivalent to the efficiency of
0.00012%.