The characteristics of the ion beams produced in a plasma focus device were
studied. In the experiment, a Mather-type plasma focus device was used whi
ch was prefilled with H-2 at 2.3 Torr. Ion species and their energy spectra
were evaluated with a Thomson parabola spectrometer. The particle pinhole
image was obtained with an aluminum filtered particle pinhole camera. The i
on current density was measured with a biased ion collector. From the measu
rement, the proton beam energy was found to be distributed from 0.15 MeV to
2 MeV. The particle pinhole image of the proton beam with an energy of mor
e than 1 MeV has spotlike patterns. The ion current density of 2400 A/cm(2)
with a pulse width of 50 ns was observed on the axis at z = 260 mm from th
e top of the anode. The peak power brightness of the proton beams was evalu
ated to be 18 GW/cm(2)/sr/keV, and the total power brightness was evaluated
to be 20 TW/cm(2)/sr.