From Italy with Love
[This text, until noted below, originally written on 09/09/07]
So today, I am heading to the Fermi National Laboratory. It's the highest powered particle accelerator in the world (Seen Chain Reaction?). Unfortunately it's not easily accessible by public transport (I checked), and a cab is out of the question, since its more than 30 miles out into the rural area around Chicago. So today, I headed over to the airport and rented a car (I reserved in advance since I knew all of this).
The first hiccup was that the hotel bus shuttle (which was awesome enough to drop me off RIGHT at AVIS) dropped me off apparently at the "preferred" desk. Apparently me walking up with my name and that I had a reservation was not good enough. I needed my preferred number, or credit card tied to my preferred account…..(I am not a preferred member). I just kept stating I had a reservation (I did not know at this point I was at the wrong desk), and the woman kept staring at me as if I was not being very helpful. Eventually, she just told me that unless I am a preferred member she can't help me. (you know if she had said this earlier it would have saved us both some stress) So, I had to walk across the lot to another building (which was actually cooler since it had better A/C in it, so I was not complaining).
So I take my Hyundai rental onto the turnpike (seriously half the roads here are turnpikes), and head off towards Aurora. I am immediately shocked by the speed limit. The normal limit is 55. And not only that, but for half the way, there was a construction zone which dropped it to 45. Ok, I thought, that's fine. I am a few hours early anyways, so I am in no rush. But SERIOUSLY, everyone else was it seems. I could only safely go as slow as 60 for most the whole way, and even that was borderline dangerous. Almost everyone was passing me at 80 or higher. Its not that they were driving poorly. It seemed that they were following normal highway driving behavior, but it just seemed that everyone else but me had complete contempt for the posted speed limit. It did not matter what the posted speed was, everyone was clearly besting it by 20-30 mph. I came up with a new word I think best describes the behavior I saw "Disregardless."
So as I mentioned, I am several hours early. The tour starts at 1pm, and I pulled off the interstate before 11am. So I had time to kill. I had figured that I would be early (when I don't know somewhere, I always allow for generous buffer times in my schedule), so I planned on spending some time at an outlet mall which is directly off the turnpike.
The people around here REALLY like their outlet mall. Maybe not as much as the one that went in down in Nashville, but definitely more than the people in Seattle/North Bend do. Its not all that big of a place (compared to Opry Mills), however, it is rather crowded for a Sunday morning. I walked around for a while, and checked a few shops I like (Addidas, Nike, Sony, Bass). I found the prices at Addidas and Nike to be exhorbinant, as well as at Sony. However the Bass outlet was awesome. They had 40% off most everything in the store, and not only that but had many items marked down before that 40%. My pair of Bass shoes now are again starting to wear out (they would last longer, but hey, if I have a sale like this, I may as well take advantage of it), so I bought a similar pair to the ones I have now (though a slightly darker color which they called Smoke….it's really brown). Next, even though I mentioned that the Nike outlet was way too expensive (seriously who pays 20-30$ for a thin pair of gym shorts), I managed to find one style of shorts which was marked as 40% off, but was ALSO marked down on the shorts themselves down to $9.99. This was an awesome deal. They must have had problems selling them. So basically for just under 10$ I picked up two pair of Nike DryFit Gym shorts. This was a sweet deal.
Finally, since my rental car has an Aux Input, I figured I would drop by sony to see if they had some eighth to eighth cables. They did. It was way overpriced (10$), but whatever, its ok.
I also stopped here for a small lunch (I am not that hungry) as well as to type this in the nice air conditioned Food Court.
Well, its now an hour left to go before the tour. I think that I am still probably really early, but I think I may still head out there, since I don't exactly know where I am going yet.
…Several days and several hundred miles later…
So, I am back at home now. I will try and pick up the story where I left off. I made several notes to help me remember to talk about a few things.
So I left the food court and headed for Fermilab. Being that it is a national laboratory, is controlled by the department of energy, and generally messes with some pretty serious laws of physics, I expected security to be extremely tight, so I had my registration paper ready to hand to a guard as well as a photo ID out as well. To my surprise, there WAS a guard station, but it seemed generally he just answered questions people had regarding where to go. I asked him where Wilson hall was and he just pointed me straight on and then the second right…. No proof that I was supposed to be there, no ID, nothing. Huh.
Ok, well I guess there is more advanced security ahead somewhere then. I drive ahead and find Wilson. It's the ONLY large building around the area, so it was not hard to miss. In fact the first thing I thought was what an uncanny resemblance to one of the buildings in college. But, I drove right up, parked in a non-visitor spot (visitor spots were labeled as 1hour only for some reason), and walked around to take pictures. It turns out that I pulled up right around the same time as someone else…who also got their camera out and started taking pictures, and from the looks of it was also somewhat geeky. I asked them if they were also there for the tour (honestly I think I thought that I may be the only one there). They said that they were. In fact they said they got the last ticket (number 100 out of 100 spots). I was shocked by this, since I had no idea so many others were also interested in particle physics. Even more interesting is that it turns out this person who I had just met randomly was also an MS intern for a few years as well during college and now worked for a government contractor. Heh, interesting, I think I can see where this is headed.
As it got closer to 1:00 (which was the time for the tour) we walked toward the building after taking pictures of various sites around, and were greeted by people handing out colored laminated cards who asked "Here for the tour?" We both said yes and received a card and were pointed in the direction of the lecture hall (the tour started with a lecture about both accelerating protons as well as the creation and storage of anti-protons). There were no questions about our registration (or who we even were). There were no requests for ID. Just: "Here is your pass…now please get in the lecture hall." Damn. (Don't worry too much, we find out later why this is not "AS" big of a deal as it sounds.) In the lecture hall was already probably a good 50 people or so. It was interesting as well because I felt like I was in good company. There actually seemed to be many geeks there as well as geeks that brought either their SOs or their family. Actually, there were several points were I was going to ask questions, but based on the other questions that went before me, it was clear I was not enough of a physics geek and decided to keep my questions to myself.
So our tour was kicked off by a slide presentation [yes, the exact one I am linking to] from Dave McGinnis. Honestly I think after I sat through it, I could really understand what they did there. (Later on much of that feeling would go away after seeing all the complex gear.) There are some key concepts to understand at this point when talking about a particle accelerator. The first is of course is that energy and mass are very related and the equation governing their relation is E=mc^2. (Duh…just reminding you..;)) The second is that when you collide two atomic particles together, you usually (depending on the energy) get several kinds of sub atomic particles which come flying out. The example in the slides are alarm clocks. If you smash two together (hard enough) then the parts will come flying out. And finally the third thing is that in order to break apart these particles and get new mass out, you have to put in enough energy equivalent to that equation I mentioned above.
So, at fermilab, the highest amount of energy they can give to a single particle is 980GeV (1eV is defined as the amount of energy gained by one proton going through a one volt battery). Thus if you had 650 billion 1.5V batteries on hand then you could generate the same amount of energy they can. Also note that the mass in the equation is very small as well. The capacity of the fermilab tevatron is 20 trillion particles, which all together weigh about 30 trillionths of a gram. However, at these speeds (.999999 * the speed of light) even this small mass can empart the same kinetic energy as a 200lb person traveling 550 mph. (DAMN) THEN consider the fact that what they actually do is that they take a proton as well as anti-proton (I will get to this in a sec) and collide them together. So really the energy levels are twice that because they can accelerate each of them separately.
So here is an overview picture of the complex:
The path that particles (most at least) take are that they are first excited by a Cockcroft-Walton generator (pic). This gives the particles 750 KeV in kinetic energy. Next they go through the LinAc (Linear Accelerator) (pic) which gives the particles 400 MeV. Then the Booster which gives another 8 GeV (the booster is a circular magnetic accelerator). The main injector then gives another 150GeV before finally handing off to the Tevatron which boosts particle energies another 900GeV.
Now the real key to all of this is the fact that they smash protons and anti-protons together. This has several benefits. One is that their mass is the same which means there is no energy "lost" when they collide. The second benefit is that antiprotons will bend in the opposite direction that protons do in the presence of a magnetic field. This means essentially that the same magnets and energy can power the particle streams in opposite directions around the ring.
The whole point of the tour that I was on was that they were going to let us see what they call the anti-proton "source." Essentially what that means is that there is a target (which we did not get to see) which protons are blasted against (at 120GeV) that produce anti-protons. Note that there are only 20 anti-protons produced for each million protons smashed. These are then caught in a magnetic field and whisked away to the Pbar source where they are accumulated in two rings. The accumulator and debuncher (This is where it started getting fuzzy to me, but essentially from what I understand, they "clean up" the particle stream using the two rings as well as stochastic cooling and then re-inject the stream back into the main injector. Where they are again accelerated to the point that they can enter the Tevatron and collide with the protons which are going in the opposite direction.
If you didn't understand any of that, I recommend the Wikipedia articles that I linked to as well as the presentation that I linked to as well. Another interesting note here though is if anyone is worried that there is a device in the suburbs of Chicago that can make Anti-matter on a regular basis… I would not worry too much about it. You see even at their peak rate, they produce 200 billion anti-protons per hour. That sounds like a lot, but remember that they only weigh 1.7x10^-27 kg each, which means to get any antimatter of sizable mass, would take some time (168 million years to make .5 g at that rate for instance). In ADDITION to that though is the fact that also at their peak rate, the machine takes 20 MegaWatts of energy. Let's say it costs you 50$ per megawatt hour, that's already $1,470,588,235,294,117 just for the power alone. Pretty much any way you look at it, there is not much you could really do with this machine beyond scientific discoveries (and health experiments…).
So, after the lecture, our group (the green group) got to go upstairs to the 15th floor where there were physicists waiting to answer all our burning questions, there were awesome views of the grounds around the building, and more importantly is that they actually had cookies and punch for us. Seriously, how awesome is this. How often do you get to take a tour of a famous physics landmark and they welcome you in with knowledge, punch, and cookies? :) I was quite happy to be there.
So after we had all the punch and cookies we wanted, it was time to get on the bus and head over to the pbar source itself. The first thing that struck me is that in practice, it was VERY clear that this device was nowhere near as simple as Dave had explained during the presentation. It was just a seamlessly endless tunnel of tubes, magnets, cables, and a variety of other foreign devices. Check out the Flickr set for more pics. They let us walk about 1/3rd of the way around the Pbar ring. (Which seemed long…but compared to the tevatron was nothing.) They pointed out the dipole magnets (these are the LARGE blue ones that bend the particle beam), the quadrapole magnets (these are the medium size red magnets which focus the particle beam), and also fine tuning yellow magnets which make small corrections as needed.
It was somewhat surprising to see radioactive warnings as well as Geiger counters on the entrances. However, the good news is that they were not showing any radioactivity.
After the Pbar Source tour, we went back to Wilson hall (actually a building next to it) in order to see both the Cockcroft-Walton generator as well as the LinAc (short for Linear Accelerator) which start off the particles into the other accelerators. Dave called the C-W generator the "Frankenstein Machine" based on its looks. I guess that I could see that. It's much larger in person than it looks in the picture is all I can really say. We continued to walk around the linac building quite a bit more. Really it seemed that it was primarily filled with power supplies, power controls, power conditioners, as well as LOTS of Klystrons. Not only that, but really BIG klystrons. Almost all the equipment there was marked as being a radiation hazard, since they use radio waves to guide and amplify the particle energies within the accelerator (see "drift tubes"). We also got to see the main control room for the complex in the linac building as well as the "dungeon." (don't ask… I have no idea)
Well, after the linac, that was pretty much the end of the tour. We were cut loose. It went over about 10 minutes or so (It was scheduled to last for 3 hours), but in general I still had time left in the day.
So, I decided to driver to Michigan. No seriously. Michigan was one of the 5 states I had left to visit (I had gotten WV earlier this year). I had looked at a map the night before and decided that it was close enough that I would go for it. Sure enough, it took just over a few hours (and another few hours back), but I made it.
However, along the way was probably one of the worse driving experiences I have had in a while. There are several reasons for this which all add up to the frustration. The first is that apparently to get around Chicago (not through, but around) you have to take toll roads. I have been on toll roads in the past I thought. You pay to get on, and then you just pay when you get off. No, that's not how these work. You pay when you get on alright, but you also have to pay again every 10 miles or so for some reason. If you don't have an "IPass" then you actually have to merge OFF the interstate and then pay at a cash toll booth. People with the automated IPass can actually just stay in the same lane even without ever slowing down. With Fermilab (which was off of a toll road) and then Michigan (which required a few other toll roads to get ther) I probably spent at least 6.00$ in change just on tolls. (Again, it's not the money that bothers me, but the fact that I have to pay in change (exact at times depending on the booth) and slowly over a long period of time, slowing down (and stopping) each time. GAH! Frustrating.
THEN, there was the fact that it seems that the whole tri-state area there (Illinois, Indiana, Michigan) simply pay no attention to speed limits; at all. It did not matter whether I was in a 70, 55, or even a 45 zone, people would drive between 75 and 90 (depending on what lane you were in). Since there is a lot of construction going on in the area, much of the interstates have been slowed to 45 mph (sometimes for many many miles at a time). It would have honestly been unsafe for me to strictly go that speed. Even going slightly over that (which was all my conscience could bear) I would still almost get rammed several times by large trucks going almost 70 mph. It did not improve either whether you were in a 55 or 70 zone either. Just pretty much all of the time no matter where you were, people drove fast. Very fast. It puts people that tend to follow the law at a disadvantage since now I am risking my safety just to follow the posted speed limit. Honestly I want to write a letter to the Illinois state patrol. I never want to drive in their state again it was so bad. They obviously have not spent the resources it takes to crack down on these infractions.
There were a few other topics I had noted I wanted to write about, so they may seem out of place. Forgive me.
It was very hot in Chicago. At first when I was on the plane I was worried I did not have the right clothes. I knew it could get cold and windy, but I had only brought shorts and a t-shirt. But oh man, that first day it was well over 80 degrees. Plenty hot enough for shorts weather. As you can see from the pictures it was a pretty nice day as well. The same was true the next day as well. I was very glad that the food court at the outlet mall had A/C. I used the A/C in the car the whole day that day as well. Shocking for September.
So, I purposefully stayed at a hotel near the airport. I knew that there was train service from the airport to the loop. I also knew that there was rental car service at the airport. So I found a hotel which had free shuttle service to and from the airport so that I could either A. Take a train if I wanted to go to the city (which I did the first day) or B. Rent a car if I wanted to drive elsewhere (which I did the second day). However, what I did not account for was the MADNESS which is these free shuttles at O'Hare. Oh my goodness, there are just tons of these shuttles and nothing but irate people who have been waiting outside for 30, 40, or even more minutes waiting for some specific hotel shuttle to arrive. It's madness. The day that I went into the City, I actually chose to WALK from the Rosemont train station back to the hotel (noted on the line on the map in that blog post). It probably took at least 30 minutes to do that. HOWEVER, what I found is that every time that I had to wait for the shuttle to come from the hotel, it took at LEAST 40 minutes (the very first time) and at MOST took close to an hour to arrive. All that time, just standing outside on a curb not knowing when exactly it would arrive. In the future, if at all possible, I want to stay at the O'Hare Hilton. It is literally across the street from the airport and is a VERY easy walk from the terminal, even if it IS 179$ a night. I probably wasted a total of 9 hours of the two days I was there either on a train, bus, or waiting for a shuttle. Don't get me wrong. I appreciated the train quite a bit. However, as mentioned earlier…it was shutdown, so that did not help much.
Also, on a fun note. While I was in Chicago, two interesting times passed by.
Both 12:11:10 09/08/07 as well as 09/08/07 06:05:04 passed by. I suppose that next year will only be 10/09/08 07:06:05 (unless you normally follow military time, and then you could have 13:12:11 10/09/08 I suppose). Fun times.
Hope you enjoyed today's science lesson. Now its back to unpacking for me.
J.P.
