No, it has nothing to do with Chicago’s bid to host the 2016 Olympics. And no, the winner does not earn the title “World’s Greatest Athlete”. Nonetheless, the Minerva Decathlon has been a ton of fun.
We had a great turnout of 22 people and great weather for ultimate frisbee this Tuesday.
Minerva, you’ll recall, is the name of the neutrino experiment that I work on at Fermilab – a (relatively) small collaboration of about 100 people. The Decathlon was the very clever idea of one of our spokepersons as a way to get our collaborators together in a casual environment. It provides an opportunity to get to know each other a little better and relax doing something fun. I’ve also mentioned that we have a number of summer students at the undergraduate and graduate level here at the lab for the summer, so we have enough people around to make it happen.
We’ve scheduled 10 events over five weeks in June and July: five different athletic activities on Tuesday evenings and five casual physics talks/discussions on Thursdays. In both cases we get together at the Fermilab Users’ Center (that’s right, Fermilab has it’s own bar and recreation building where the best bartender in the world takes care of everyone) for a few drinks either after (for sports) or during (for talks) the event.
Me sadly attempting to defend the seemingly undefensible Thomas.
So far, we’ve played volleyball, soccer, and ultimate frisbee. In each case we’ve gotten people to come out who have never played the sport before (I mentioned it was casual) and others who participate in leagues. This past week, I was one of the former. Thomas, who I am shown attempting to defend below, appeared to be one of the latter. “But, Dave, what’s that giant brace on your old, decrepit knee?”, you ask. Indeed the game ended sometime in the second hour when I came down wrong and had to hobble off the field (12 year old ACL injury, so it happens all the time unfortunately).
The talks and physics discussions are designed to be just as relaxed, so everyone feels welcome to ask any and all questions. We’ve had two in the lecture series so far. The first was on the details of how we use high energy proton accelerators to make intense beams of neutrinos. The second, earning among other prizes, that for best title (title slide shown below), was about the graduate research of one of Minerva’s post docs.
“Nothing goes to Something plus Nothing…“? Okay, maybe that’s a little physics humor, but I think its hilarious. The goal of the experiment was to search for the exceedingly rare decay of the neutral kaon particle into a neutral pion particle plus two neutrinos. The extreme challenge of it (and the humor for physicists) is that none of those four particles can be directly seen! Particle physics detectors all rely on the interaction of charged particles in some detector medium. Individual charged particles actually leave very distinct tracks as they travel through a volume of gas, or a tank of liquid, or a solid scintillating material, for example. Neutral particles do none of that. The only way to detect the K -> π + ν + ν reaction is indirectly because the neutral pion will immediately decay into two photons. These two photons will interact with materials and can be “seen” by the detectors in the experiment. This was the signature that Gabe’s experiment looked for.
Display of an event in the E391 experiment where a kaon decays to three neutral pions which each decay to two photons making the six photon signatures shown.
The slide to the left, taken from his talk, shows the regions where energy is deposited in the detector for the case of three neutral pions decaying into a total of six photons (a background for the type of reaction they were searching for). You can imagine that a single pion event would only have two such deposits both consistent with being a photon.
The analysis of the E391 data set showed no such events, but the theoretical prediction for this reaction is that it should happen somewhere between 1 in 100,000,000,000 (1 in one hundred billion) and 1 in 10,000,000,000,000 (1 in ten trillion) times that a kaon decays, making it a challenging search indeed. A next generation experiment is being planned now.
Next week we play 16″ softball on Tuesday (there’s a diamond at the lab) and the talk for Thursday is “How to Explain Neutrino Physics to your Relatives” which I think is a great idea. However, I understand the father of the person leading this discussion is a fellow in the American Physical Society, so hopefully she’ll cater the discussion to a crazy ol’ Aunt or something instead!
