December 3-7, 2004
I've known that on December 3 (the day I originally wrote this!) we were going to start commissioning the beamline...but somehow I had no idea how long the process would take. There are detectors all along the beamline, and lots and lots of magnets.
Getting the beam to the very end of the beamline requires so many things to be right all at the same time: starting with the protons, they have to be at just the right energy, and then the magnets have to have the right current going through them so they bend the proton beam just the right amount. Behind that, you have to make sure that the power supply provides the right current..But even that's not enough--you also have to make sure that all the magnets have been located in just the right place, so that you know how far "bend just the right amount" means in the first place! And of course, there are so many different ways you can measure the particles as they go down the beamline: you can measure the total charge that goes down the beamline to get the number of protons, you can measure in a few different ways what the average position is, and you can even measure how broad that beam is. For example, The NuMI beamline, has detectors to measure average positions of the proton beam at about 20 different places (called "beam position monitors"), and detectors to measure the average and width of the proton beam in 10 places with a totally different kind of detector (called "profile monitors").
Of course I say "you" have to get all these things right, but really there are probably about a hundred people who have in one way or another been part of all of these different steps. My part was to help design, install, and test the detectors at the "end of the line", as well as lots of coordination between folks building all of the different upstream
instrumentation.
The one thing I knew before everything started was that we had 12 hours to get the beam from the Main Injector: and when I say "we" this time I actually mean a few experts on the experiment who were changing magnet currents (which change the angles that the protons get bent) in the Main Control Room (MCR). I was part of the cheering squad up on the 12th floor "MINOS control room" of the high rise, watching (thanks to computers and the internet) all the various detectors do their collective thing.
So lots was going on in the Main Control Room but we didn't know when the action would start. I was talking to someone down the hall from the 12th floor "control room", when all of a sudden I heard someone say "they've made it to 101" which means the beam had been extracted out of the Main Injector and made it past the first big bend to our own set of proton detectors. I ran into the MINOS control room, looked at the screens showing distributions in the first out of 
the 10 "profile monitors" and the adrenaline started flowing.
The crazy thing that happened next though is that I had a severe mental flashback to being in labor: I didn't know (in the beginning) when the next contraction will come, and I also didn't know how far the baby would progress with each contraction. With each new profile monitor that was passed, I was reminded of how the baby's head goes through the different stations (only with a lot less pain).
The more the day progressed the more similarities I found: and
although it took 2 or 3 hours to get to the first two stations, then a
half hour later they tweaked enough currents to get through three new
stations at once!
More and more people were gathering on the 12th floor as we we got closer to the end of the beamline--and each time a new profile monitor position was passed I ran over to this big poster and wrote the time (and date, I didn't know then it would only span one day!).
Finally, when the proton beam was successfully steered to the end of the beamline (about 3600 feet away, and 5.5 hours after the first pulse) everyone was cheering and we all went down to the "main control room" and had champagne and signed that same big poster. 
During the course of the day I ran this birth analogy past a few other people who have witnessed their wives giving birth and no one else was reminded of that...except for one friend (Nancy Grossman) who did agree so maybe I wasn't completely crazy. But just like giving birth, once the baby is out then there's lots more work to do...I will spend all of tomorrow in the main control room myself doing studies of the detectors I helped design with real protons!
Post Script (December 7):
I feel even more vindicated in the whole labor analogy today, since someone I hadn't seen since before December 3 actually walked up to me and said "congratulations, it's a beamline!". The mood here is really festive due to the fact that it took only 10 spills (10 shots of protons) to get the beam the entire length of the beamline.
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