No no no, no black holes here, but I just wanted to mention something that goes essentially unmentioned in the current torrent of press on the upcoming LHC start up.  As Monica mentioned, there will only be single beams going ’round the ring.  But more importantly, it will be at “injection” energy (450 GeV), i.e. the energy provided by the SPS, the previous ring in the CERN complex.

So even if (and ideally when) the LHC folks bring two of these beams into collisions, the energy will be much lower, i.e. 900 GeV.  This is an energy well-known to high energy physicists from the 80’s (as shown in the mini-history above) and there are quite a few UA1 and UA5 papers from that energy.  Thus, it will give the current batch of experiments the chance to turn back the clock a little bit, and see if they got things right a generation ago.  From my awed perspective, as I consider the complexity of the machine and especially the detectors, I can’t imagine a more useful thing to do to reassure ourselves that things more or less make sense.

And so you all can put those death threats on ice, at least for a few months.  The LHC as we will know it will not be fully operational on Wednesday after all.  That said, a short recap of HEP circa 1987 (”Rick Astley” physics? “Bon Jovi” physics?) should still be pretty exciting — and certainly benign by all accounts.

(A little aside, it’s surprisingly hard to put accurate points on the plot above.  One can find start years easily.  Similarly, one can find the highest energy each machine reached.  So it really seems that historically, machines rarely start at their peak, and generally take a certain amount of time to reach full capability.  One wouldn’t be off base for presuming a similar story at the LHC.)

(Another aside: why the heck did I have to make that compilation myself?  Does anyone know of a bigger/badder/better/more version?)

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