We did a little unpacking last week, but this week we had to do some slightly more serious sorting. Each of 16 boxes had to be opened and then parts sorted by type. Some tools were also arranged in cabinets. For our two longest boxes we need to empty them completely so that they could be removed leaving room to work. As you can see in the picture, we have the boxes lined up in the storage area with just enough space to walk past them. In side the boxes, there is... you guessed it, smaller boxes! Some of the cardboard boxes needed to be opened, but others we just sorted by their label. Also, I now have access to a lifetime supply of bubble wrap. If the epoxy (see below) drives me too crazy I might just end up wrapping myself in all the bubble warp I can find and jumping off the roof. I wonder if sufficient bubble warp could handle a 90g deceleration like the Mars landers?
After sorting, part of a day was spent moving four of the chambers from the stacks down onto the floor. Two movers came by to do the work. Reza and I mostly just watched, we just needed to be there to let them in and make sure the chambers were put exactly where we wanted them. The process became far more tedious than we had hoped when the movers suddenly left without saying a word. By the looks of things we figured they had left to find longer straps to fit around the boxes. But, minute passed on to minute and soon it seemed if they had forgotten us. Not even a long coffee break could explain it. After our second phone call we were told they had been given another project and we should just wait. The waiting wouldn't have been a problem at all if we knew when they would return, had an Internet connection, or at least brought a book; but instead we just stood around and drooled for two hours or so.
Hovering dangerously over the Italians' chambers, our chambers are almost in position next to the stairs.
As you see below, each chamber is made up of six layers of tubes, three above and three below a central frame. The boxes you can see in these pictures have steel frames inside and are lined with Styrofoam. The chambers are nestled in the center of this. I don't know how much they weight but I expect they are relatively light since most of their volume is gas filled aluminum tubes. There are frames for holding, rotating, and moving the chambers; but, initially we just need to access the ends. So, we brought the chambers down in pairs and opened the ends of the top box to access the ends of the top chamber. This puts it at just about the right height to reach in and work while sitting in a chair. In the upside down T-shaped panorama you can see the boxes open and the chambers inside exposed. A chair and a lamp are sitting in front of the chamber at the back right.
The interior of bld. 184 after we moved two pairs of chambers down to the floor and opened the ends of the boxes.
A few other things of note in the T-shaped panorama: the yellow thing on the ceiling is the crane. In the back are the sliding doors which enclose the loading area. On the right in yellow frames are the Italians' chambers. Behind them on the other side of the white wall is the machine shop. Above that is where the gas canisters are stored. (We will use a lot of gas, each chamber will be pressurized to 3 bar with a precise mixture of argon and carbon dioxide.) On the left you see the stacks of chambers we will work on (and more are coming). In front of them is a stack of wheeled frames on which the chambers can be mounted. Behind the white wall on the left is the clean room that is not is use. And, at ground level to the left is the storage area.
In the backwards-L panorama you are looking to the left toward the storage area. You can see a small crane mounted to the wall. Below it are our carts which need to be setup with all the equipment we will need for assembly and testing. I think the white thing on the cart in the middle is a mass spectrometer. A chamber can be mounted on the blue frame in the foreground which allows the chamber to be rotated.
Getting the colors correct in these pictures is quite a tricky operation. The problem is that for much of the day a significant portion of the light comes from the artificial lighting and from the windows. Adjusting for the artificial light, the windows tend to look too purple. Nevertheless, the color of the floor is no mistake. It really is that shade of green. (In fact this is the third reason why it is difficult to render all colors correctly, everything is lit from below by a little bit of green light.)
The truth is I'm not complaining, but our first real task happens to be the most mind-numbing one of them all.
The situation is this. The chambers we work on are made up of long tubes about 3 cm in diameter. The tubes contain a wire running down the middle. The tubes need to be pressurized with a specific mixture of gas. In operation a very high voltage is applied to the wire and if a muon happens to pass through the gas ionizes and a small current flows into a detection circuit. This is how muons, which are very heavy electrons, are detected and tracked as they leave they leave the Atlas detector. So, on the end of each tube are two pins for the voltage and a small brass tube (called a tubelet) through which the tubes are filled with gas. The problem is that after starting construction on the chambers the University of Michigan discovered that the tubes would not maintain pressure. The leaks happen at the joint between the tubelets and a nylon piece at the end of each tube. Also, the particular type of brass used to make the tubelets develops invisible pinhole leaks at the bends. This was especially a problem for the Michigan team because, unlike others, they started early and were completely on schedule with their construction. So, they discovered the problem early and were able to warn other teams. (We are only building a fraction of the chambers needed for Atlas, specifically we are working on the middle of the three end-cap layers.) Others, who still hadn't started construction, could switch to a different type of tubelet or in some way correct the design flaw relatively easily. We are stuck with the flawed chambers we built early on.
The solution is not pretty. We need to coat every bend in every single tubelet with epoxy. We also need to fill the connection with nylon piece with more epoxy. All this has to be done while also carefully avoiding the electrical connections or unnecessarily gluing the various pieces together. The process is exteremly tedious and especially difficult because you need to get all sides of a very thin tube coated (most notably the back, which is hard to see even when employing a dentist's mirror). Thankfully you don't have to be very neat. The epoxy naturally smooths itself out. All that need be done is cover every bit of surface.
If you look closely in the pictures you can do the math: each group contains 24 tubes, there are eight groups across and two layers of groups. That is 24 * 8 *2 = 374 tubes in each chamber. There is a tubelet connected to each end for a total of 748 tubelets to epoxy on each chamber. Some chambers have already been fixed. I don't know how many there are for us to epoxy, but we have been assured that it will not go on forever and will be broken up with more interesting work.
It's not a job I relish. But, strangely, I don't mind it too much. It gives me time to listen to music and enjoy the very nice headphones I purchased last summer. It also gives me time to ponder the chain of events that brought me to here and now and this sticky situation in a country I never expected to be living in and working at a job I never expected I would find. This is the sort of work I have always thought I would enjoy, not applying epoxy but more generally technical scientific work. I wonder how long it will be before I tired of it, but it is a refreshing change from math, getting my hands sticky instead of chalky.
Compared to Ann Arbor the weather has been delightful. It's no Hawaii, in fact we have had more snow than we typically see in Seattle, but the temperatures have almost never dropped below 30 F. Just a couple days after arriving we left the apartment to find an interesting precipitation which lies somewhere in the no-mans-land between hail and snow. It's a region of the weather spectrum that is rarely tred in my experience. The "flakes" were airy like snow but small and round like hail. It put a nice layer on the ground, but lasted only for a very short time.
More recently we had some authentic snow. It's nothing to write home about, but it did put a couple inches on the ground. By evening the snow had mostly melted. I noticed that with the snow I didn't see the sheep which normally reside on the center hill overlooking our building. On the way to lunch I took a few minutes to discover their hideout. It turns out to be under the bridge leading into the center circle.
The sheep take shelter from the snow under the bridge that connects the inner circle to the outer circle.
Maybe a description of the area around the building is in order. You
can get a good idea by looking at the
map around 184. Building 184 is in a circle formed around an old
collider called Intersecting Storage Rings or ISR. ISR was
machine in the world to acheive proto-antiproton collisions under
controlled conditions. It last ran in 1984 and was superceded by
LEP which involved a much bigger circular tunnel marked out on a map and in
an aerial view. The tunnel is 8 km in diameter and about 100 m
underground. New and improved equipment is being added to the tunnel
right now. The project is called LHC.
Snow on our CERN issue Peugeot Partner, a very-minivan.
Anyways, now the buildings and tunnel that once formed ISR are used for other things. In our case the Atlas experiment (which will make use of particles accelerated by LHC), and as you can see in one of the sheep pictures the "LHC magnet assembly project" is also in the ISR. A road from the outside passes over a bridge and drops down the side of a large central hill and into a low circular area. Buildings butt up against the outer walls of this circular valley and connect to the tunnel that once held the ISR beam line. Though I don't have keycard access I once got to walk through the tunnel area behind our building. It seems to be filled with makeshift offices and lab space and is impressively large. In fact the reason for our journey around the back way is might be related to the current topic, the snow. It was the first day it snowed seriously and when Reza and I arrived we found everyone who uses our building milling around outside. The key card lock had stopped working, I'm guessing because of the cold weather. Zhengguo took us around the back way in an unsuccessful attempt at finding another way into the building. At least it is nice to know our building is secure.
There was talk of visiting Geneva Friday evening, but it didn't happen, mainly because Reza and I spent too much time shopping. We headed to Thoiry to shop at Migros, which is pretty much the same as Meijer or Fred Meyer but somewhat smaller in scale. (Suspicious, that similarity in name; is these all just a single multi-national one-stop shopping monopoly? Yet one might consider it comforting, there is at least one thing on which the "new" and "old" worlds agree: life is so much easier when we can pop yogurt and underwear in the same shopping cart.) On the whole things seemed a bit pricier than in the US; and this is France, everyone says Switzerland is significantly more expensive. Of what I bought the best deals seem to be yougurt and brie. Mmm, dairy products. Maybe the French don't give their cows the two coffee breaks, 1 1/2 hour lunch, and five weeks vacation that is everyone's right. But on certain days and in certain moods I might be inclined to give it all up if instead I could lead a life of nothing more than grass nibbling in almost any scenic pasture nearby.
Oh, and bringing us back to the realities of shopping: while perusing
the ailes I realized that I'm so much closer to the source of my
favorite jelly, Bonne Maman! I was almost in a panic when I couldn't
find my favorite flavor, "4 fruit" (cerises, fraises,
groseilles, et framboises), but luck was with me, that specific
flavour comes in two-packs with
20% de produit en
plus for close to the same price as a single measly jar back in
the US! And speaking of the sweeter things in life, right now I have
the remains of a Lindt "Noir Orange" at my bed side. In my opinion it
is their best chocolate, but unfortunately I don't recall seeing that
particular type at the Village Corner. I expect better of the VC.
Actually, I've only found one store that has that specific kind of
Lindt so I'm now trying out the pear brandy variation. 'Times.
On a different food related topic I will mention the pinacle of French cuisine: pizza. There are a surprising number of little pizza trailers like the one seen in the picture here. Every town seems to have at least one (except Prevessin where I'm living right now) plus the possibility of more permanent establishments emblazoned with "Pizzaria" in neon. The picture shows one of two in St. Genis, the French town closest to CERN. Jeff said this place is a little better than the other one, but I noticed the other guys were wearing the snazzy cooks whites, jacket and hat, and I've got to respect that (or at least feel some tittery thrill.) Pizza options are limited, you choose from a list of about 10 combinations, all include either ham, pepperoni-ish something or other, or anchovies, and none involve vegatables like green peppers (onions and mushrooms are the closest you come). And the truth is that this weekend I broke open a frozen pizza and found it to be tastier than their fresh pizzas. That is not to say that their pizza was bad, just average, while the frozen pizza was quite good.
We went to get the pizzas in preperation for a trip to the movie theater. We drove to Meyrin and saw The Last Samurai at what seemed to be a very new movie theater. They were very in a lot of other ways. With a student discount tickets were 15 Swiss francs, which about $12! But, by buying a book of 10 and sharing we were able to get them for only 12 francs a piece (about $10). That is very expensive. I need to see at least four more movies to use up my half of the tickets. Despite the cost, I will grant the theater this: the design is a very plush one. The seats are large and reclining. Every seat had a good view. And, the arm rest were doubled so everyone had their own pair! Once I sat down I (almost) forgot about the hunderd franc note I had to slap down a moment ago to buy that book of tickets. The movie was ok, nothing special. The battles are very gruesome. There is nothing fresh or inspired about the story, but I give credit for a few humorous moments and the astetics of an expert wielding a sword. (I just watched the first half of my Samurai Fiction DVD which my sister gave me for Christmas. It's got just as much good sword wielding times, but with a whole lot more fun humor and parody.)