As an experimental physicist you actually get to DO stuff17th April 2017
One of the main things I appreciate being an experimental physicist is that you actually get to DO stuff.
I mean you go into the lab and literally DO stuff. You have to turn knobs and push buttons in order to record measurement data or to calibrate your detector. There is also a lot of technical stuff like clamping together a vacuum system or building something complex with various tools, but you also do a lot of simple hands-on stuff.
I found myself thinking about this the other day as our students and I were wrapping graphite blocks for TRIUMF’s Ultracold Neutron Project. We surround our neutron source with graphite blocks wrapped in aluminum foil to reflect stray neutrons back towards the heart of the experiment in order to increase the neutron density. The neutrons convene on a bottle of superfluid helium where they are converted to the ultracold neutron energy regime (check my first blog post for more details about TRIUMF's ultracold neutron source).
So why do you have to wrap the graphite blocks in aluminum foil? Graphite is a very brittle material, and just handling or transporting it will spread graphite dust and crumbs all over the place. Dirt itself is a nuisance in an experimental facility, yes, but there is a much more critical issue at hand: graphite becomes radioactive when irradiated. In our experiment, this process happens due to the proximity to strong gamma and neutron radiation from the nearby neutron spallation source. It is obviously imperative to ensure that none of the graphite spreads around after it becomes radioactive. A simple but tedious remedy is to wrap the blocks in aluminum foil -- you can’t use plastic wrap because most plastics disintegrate after exposure to radiation fields, which would defeat the whole purpose of wrapping.
We had to wrap about a dozen blocks, but because of their weird shape it still took us a few hours to get it done. The students who were helping me, Beryl Bell and Matthew Palmer, are real experts in wrapping graphite blocks -- they had previously wrapped several hundred smaller brick-like blocks with aluminum foil. That was back in December -- great training for wrapping holiday presents!
Wrapping blocks next to Beryl and Matthew, I realized just how sharply the amount of hands-on work had declined along my path as a physicist. When I was an undergraduate student, I was doing way more tasks of that nature! It was the same during my PhD -- LOTS of daily hands-on tasks. However, when my first postdoc appointment came around, hands-on activities were already becoming less and less frequent.
(As an aside: obviously, the amount of hands-on work you perform will depend on your project and the kind of physics you do -- for some students or researchers in big experiments with high data rates such as ATLAS or other collider experiments, “technical” tasks can also consist of writing pieces of code rather than soldering electrical circuits, cleaning the lab, or wrapping graphite bricks!)
As a research scientist on a tenure track position, the profile of my work activities and responsibilities is very different than what it was as a student. Apart from the more scientific things like devising new experiments or deducing and interpreting data from the last measurement (which are the most fun), I also do quite a large amount of writing. Ideally, I am constantly working on some publication (fingers crossed), or also composing internal reports or, very important, funding applications.
My work with Beryl and Matthew reminded me of how hands-on work helps me to clear my mind when I'm stuck with something, and helps keep my work days full of variety. Even though I do less of the hands-on activities now as a research scientist, I still relish being able to roll up my sleeves and take part in these activities when I get tired of sitting in my office chair for too long! Life as an experimental physicist is never boring, and even though -- or maybe exactly because -- one moves further along the academic path, you still appreciate even the smallest hands-on tasks -- like wrapping graphite blocks in aluminum foil.