Experimental Study of Rod Pinch Diode as Radiography Source at 1 MV

The rod pinch diode is a cylindrical pinched beam diode that provides an intense small diameter bremsstrahlung source for radiography. For this work, according to particle-in-cell results and the pulse power generator parameters, the 1 MV rod pinch diode was designed and studied experimentally. The experimental data were obtained on the 1 MV facility between 0.8 MV and 1 MV at 20 to 40 kA with 120 ns FWHM. The diode impedance behavior was studied. The average time rate of change of the diode impedance is less than 0.5 Ω/ns at magnetically limited stage and more than 2 Ω/ns at space charge limited stage. The diode impedance is between 26.4 Ω and 36.7 Ω. The dose of 1 R at 1 m is obtained with 1.5 mm anode. Dose obtained by experiment can be fitted by voltage Ud and current Id as D(R=1 m)=120U1.55d∫Iddt. The X-ray pulse width is proportional to IdU1.55d.