The Helium-Jet Ion Source pt. 2

So now that we've got a beam of neutral atoms, we need to ionize them. That's where Argon plasma comes into play. Recall that a plasma is a partially ionized gas that has it's electrons on the outside with the ions and neutrals in the center. As this beam of neutral atoms stream in, the electrons strike the neutral atoms causing an electron from the neutral atom to be stripped off, which is called electron impact ionization. The chamber that houses this plasma is also negatively charged. Since the ions we care about are positively charged, they get sucked out of the chamber creating an ion beam! Now, I've skipped a lot of the details, but that's basically how this thing works.

Switching gears. This entire week has been devoted to designing the argon and helium gas delivery systems. Since very little argon is actually used, which means the tank is small and light, we plan on mounting that on a sheet of metal or wood (haven't made our decision yet) along with all the transport lines and a flow regulator. We also want the flow regulator for the helium as well. Since we can't be in the room where all of this is located during the experiment (since the room is being flooded with radiation) we want all of this in a nice, compact design such that we can put a video camera and monitor things from a control room. I've already figured out what components we're going to use, but now I've got to put it all together. I had heard of Google Sketchup, but had never used it before. It's a free 3D modeling program that's good for when you need a simple visualization. I read that it has all the doohickeys and doodads that other 3D CAD software has, but I also hear that it's atrocious for real engineering drawings. Thankfully, I just wanted a rough "sketchup" of the design.

I also got to meet with the rest of my group yesterday. I really only work with JJ and a lot of the other people in the group are in buildings so I'd never met many of these people before. I got to see a seminar on nuclear astrophysics from a potential new hire as well, which was fascinating. I was surprised that I was able to follow as much of the presentation as I did. I guess I did learn something during my undergraduate after all! I also got to network with some people that I could do research with as a grad student later on.

Speaking of grad school... I'm still trying to figure that one out. I'm certain that I want a Ph. D., but I'm trying to decide between nuclear physics and nuclear engineering. I like the idea of helping build things that will pave the way to the future, but I also like the idea of doing the science necessary to build those things. I'm going to be looking into possible programs with the Department of Defense and Department of Homeland Security as well. That's where all the cool classified stuff goes down. Tennessee's state legislature is also voting on a bill right now that will, if passed, provide funding in the hopes of getting more Ph. D. seeking students working at ORNL, specifically those interested in nuclear physics/engineering. That's good for me :D

I hear this pizza place around here called "Big Ed's" is awesome. Pizza being the best thing invented since best things were invented, Jeff, my roommate, and I are going to go check it out. Mmmm.... pizza....