SPATIAL AND TEMPORAL CHARACTERISTICS OF THE X-RAY EMITTED BY 1-J 50-NS VACUUM DISCHARGE

The X-ray emission from a source based on a small vacuum discharge has been studied. Two different X-ray pulses whose intensities vary versu s the ''anode-cathode'' distance are identified. Time integrated pinho le images show that the whole anode, and the teflon insulator emit X-r ays. Some of the X-ray emission is found to originate also from the vi cinity of the tungsten anode. The temporal behavior of the X-ray varie s with respect to the distance between the anode and the cathode and i s in satisfactory agreement with the EEE model; three different cathod e geometries have been tested: hollow cathode, hollow conical cathode, and massive or needle cathode. The spatial distribution of the X-ray sources is obtained by means of a sensitive imaging device. Some X-ray spots appear in the discharge gap near the anode tip, which are simil ar to ''hot spots'' found in more powerful discharges.