Hello! I’ll probably write more technical posts later, but since I’m a new US LHC blogger, I thought I would spend this first post talking a little about my background and how I decided what kind of postdoc position to look for. Lately, quite a few of my friends in their last year of graduate school have been asking about the latter.
I’ve been with Columbia University for almost a year now, having defended my PhD thesis at the University of Massachusetts, Amherst on June 10, 2011. I knew I wanted to stay in the field after graduating, if only for the fact that it would have been a shame to look at only 42 pb-1 of data, see no new physics, and miss out on being around for (what eventually became!) the biggest particle physics discovery in decades. Just to give you an idea of how much data I had for my thesis compared to what we have now, see this histogram showing the integrated luminosity recorded by ATLAS in 2010, 2011 and so far in 2012:
I was that green line.
Before applying for postdoc positions, I needed to decide what kind of research to do in the next stage of my career, and where I would want to do it. Almost all the work I had done as a graduate student was related to the muon spectrometer on ATLAS; from helping in the installation and commissioning of the muon precision chambers, to muon reconstruction performance studies, to measuring the first Z→μμ cross section at sqrt(s)=7 TeV and finally performing a search for new physics in the high-mass tail of the mu-mu invariant mass spectrum. Muons were my thing.
The advice I got from most of my colleagues at the time, including my adviser, was to switch experiments. The reasoning made sense. If you stay with the same experiment for your postdoc, you miss out on a free pass to do research on something completely new. It’s a rare opportunity to start from scratch while still having some allowance for time to catch up.
But that was the thing….most of the people I was seeking advice from had come from other experiments to the LHC, not the other way around. In fact, I was one of the first US students able to write a thesis on LHC data (the delay partly due to the incident in 2008….let’s not talk about that). So where could I have gone from here? If I wanted to stay in collider physics, I needed to stay at the LHC.
Knowing I wanted to come back to CERN, it also took some time to figure out exactly what kind of analysis I wanted to work on after the PhD. I talked to a lot of people that semester, asking who would be working on what and getting lots of advice. I certainly had many interesting options for research, but it wasn’t until I was sitting in a talk about the evidence for forward-backward asymmetry of the top quark when I thought now hey, top physics…
In the end, I decided to make as big of a switch as possible while still staying on ATLAS, moving from the muon spectrometer and dimuon analyses to work on top quark physics and jets at an institute responsible for the liquid argon calorimeter electronics. The move seemed to cover the best of all possible scenarios…I didn’t need to worry about the year-long wait to qualify for authorship or to figure out ATLAS software, but I did get the opportunity to learn something ultimately different when it came to hardware work and physics analysis. However, because of the size of the collaboration, where each subdetector community has roughly the same number of people as one Tevatron experiment, it took some time to get enough exposure to be recognized for the new work I was doing. That will be the case whenever you start a new job, no matter what.
Even more difficult was going from feeling like an expert in my thesis topic to suddenly being thrown in the deep end of a new topic amongst other experts. I found I wasn’t the only one who experienced that. Before I began, a few senior postdoc friends of mine who wrote their PhDs at the Tevatron said that their first year at the LHC felt just like being a brand new graduate student all over again and that it was hard to feel like anything really substantial had gotten done during that time, just because there was the additional learning curve thrown in. When I looked a little sad, one of them said “well for you, since you’re staying on ATLAS…maybe only 6 months.”
My advice to anyone wrapping up their graduate studies and thinking about getting a postdoc would be to talk to as many people as possible and get as many opinions as possible. My experience is just one of many! I can say though that the more I knew going in, the easier the transition was, and now one year later everything is going really smoothly.
Anyway, have a look at my upcoming posts, where I’ll talk about jet substructure, new physics searches involving the top quark, and whatever other cool beyond-the-Higgs stuff is happening at CERN.