New Anode Almost Done
Our new anode is almost done! We got the anode stalk (the vertical part that goes into the vacuum chamber) a few weeks early and inspected it carefully. Here it is, sitting on the anode base. (The whole thing is inside a sealed glove-box to protect us from any potential exposure to beryllium dust—although we doubt any is present.)
The base in turn sits on the steel plate that connects it to the circuit that supplies our mega-ampere current. For inspection, the assembly is pointed up, while in use, it will be pointed down. The gap between the two beryllium parts (the shiny metal) is deliberate. The electrical connection is made with a layer of indium, a soft metal, at the bottom of the gap. The gap prevents current from arcing across. All the current has to flow though the indium, with a resistance of less than one millionth of an ohm.
The diameter of the anode is 5.6 cm or 2.2 inches. In operation, up to 60 GW of electric power will flow through the anode, about as much as is consumed in the North East United States. However, peak power lasts less than a microsecond, so the anode can take it.
We did find a small error in the anode stalk, so it needs to go back to the manufacturer. But we expect correction will occur swiftly and we are still on schedule for re-starting experiments in May.