People often wonder how we at ATLAS feel about those bozos our good friends at CMS, and vice versa. The two experiments are trying to discovery exactly the same things, and as Monica discussed a while back, trying to keep from getting scooped by the other experiment will be nerve-wracking. Personally, I like to think of CMS as the baseball team on the other side of town. Yes, we plan to beat them at everything, every time — but deep down, we know that if they weren’t there, we couldn’t play baseball.
Obviously we don’t literally need there to be a competing detector in order to record events at the ATLAS detector or look for new physics in them, but having two detectors is actually critical to the LHC’s overall goals. At many places — especially where new things are being tried — the detectors use different technologies. For example, the T in ATLAS and S in CMS represent the very different magnet configurations used for the two detectors’ muon systems. The “worst-case” reason for this is that one detector might incorporate something that never works — and while that would be terrible for the people on that experiment, it’s a lot better to have a backup that can still do the job. But, in fact, ATLAS and CMS both work just fine so far, and we expect them to continue doing so, which brings me to the second reason that they’re complimentary: we need somebody to check our results. Of course, we at ATLAS want to (and, needless to say, will) discover everything first — but if CMS never sees the same thing, a discovery will be pretty hard to believe. The particle physics community really needs two detectors with different designs and different teams and different analysis strategies to get the same answer before we can be sure of what we’ve found. (Ideally, we’d have different accelerators too, but that’s a little out of our price range nowdays.)
I’d even say it’s a friendly rivalry, more like the San Francisco Bay Area than New York or Chicago. Although it’s hard to say — I’ve seen hats that say A’s on one side and Giants on the other, but I have yet to see any ATLAS/CMS merchandise.
Tags: ATLAS, baseball analogy, CMS, competition
