XUV radiation from gold exploding pusher targets irradiated with protons

Abstract

In 1982, proton beam experiments were carried out on the PROTO I accelerator with up to 0.65 TW/cm 2 incident on gold exploding pusher targets. The total proton energy incident on the target was as high as 2.8 kJ, with up to 1.32 kJ deposited in 2.5-μm-thick gold cones, giving a specific power deposition as high as 27 TW/g for 1.5 MeV incident proton energy. XUV radiation (10 eV -2.5 keV) from the gold conical exploding pusher targets was measured with x-ray diodes (XRDs) and PIN solid state diodes. High resolution, time integrated XUV radiation measurements (60–400 eV) were also obtained with a 1-meter grazing incidence spectrograph. The radiation from these targets consisted of three major components: (1) XUV radiation from a high density but low temperature plasma radiation at the inner surface of the conical exploding pusher target, (2) high energy XUV radiation from a low density, high temperature plasma produced by the stagnation of the pusher material on axis, and (3) 2.1–2.2 keV gold Mα, β inner-shell line radiation from the inside surface of the target. The equivalent brightness temperatures at the inner surface of the conical targets were between 18 and 32 eV, assuming a 0.07 cm 2 emission area.