Yesterday we visited Fermilab, home to the world’s largest operaring particle accelerator. I hear you say: but wait, isn’t the Large Hadron Collider at CERN in Switzerland larger? Yes, but it isn’t operating yet; they’re still fixing the mess since it broke down in September last year. When the LHC goes online it will be the world’s largest and highest-energy particle accelerator, with a tunnel of 17 miles / 27 kilometers. The Tevatron at Fermilab is still 3.9 miles / 6.28 kilometer. You can see it on the following map.
Fermilab lies about 45 miles west of Chicago and about 90 minutes from where we live. We did the 10:30 tour, which is held every Wednesday, and it was excellent! We got to see a lot more things than I thought we would.
We did the Eli’s Cheesecake Factory tour a few weeks ago and that place was locked down by the government after 9/11. They used to show you the actual factory with the ovens, but now they’re only allowed to tour the shop and a small section of the packing department. Based on that experience we thought we surely wouldn’t be able to see much at Fermilab either. After all, if they don’t let you see a cheesecake oven for security reasons would they let strangers anywhere near the expensive and dangerous equipment of a multi-billion dollar particle accelerator? Well, they do! We were pleasantly surprised that the tour showed us lots of places where the scientists work.
By far the coolest thing I saw yesterday, and one of the coolest-looking things I’ve ever seen, was the Cockcroft-Walton generator, which is the first stage in the acceleration process. The device looked liked something from the Starship Enterprise. Check this thing out:
Doesn’t that look amazing? We got to see this large voltage multiplier from a window above. This room is where the protons start that eventually will end up in the Tevatron where they’ll zip around in circles at more than 99.999% the speed of light.
The tour actually started in a huge building called Wilson Hall, named after the lab’s first director Robert Rathbun Wilson. He was responsible for finishing Fermilab ahead of time and under budget in 1972. He also created many unique sculptures that can be seen around the roads and buildings at Fermilab, as well as the unique shape of this high rise laboratory building, which has become the symbol of Fermilab and was named in his honor.
The first part of the tour took us around the 15th floor of this building, where our guide (who was great and very knowledgeable) showed us around some displays and models of magnets and other equipment that they use. She explained about protons and anti-protons and dark matter and quarks and lots of other things that went way over my head. It’s all very interesting but very complicated too.
One of the mind boggling objects on display was this billet:
To make the superconducting magnets for guiding and focusing the protons in the accelerator, they needed to make superconducting wires. One of these 24-inch billets would get rolled and stretched into a thin wire about 40 miles long! The billet is made out of 2,100 rods of niobium titanium encased in hexagonal copper tubes. After the billet is rolled out the wire is only 27 thousandths of an inch in diamater, but it still contains the 2,100 rods. Isn’t that incredible? It kinda reminded me of how they make taffy.
After this initial part we went down to the ground floor and peeked inside the impressive auditorium (where they hold many cultural events and lectures for the public) before walking around some of the labs. We got to see dozens of real scientists at work as we walked through the hallways of one of the buildings. We got to see the Cockcroft-Walton generator and lots of other equipment. There were a lot of old computers that were huge and hadn’t been replaced since the place opened in the 1970s. They looked like they came straight out of Dharma Initiative station. 😉
One cool thing they do in this building is treat cancer patients. Over 3,100 cancer patients have been treated at the Neutron Therapy Facility since it opened in 1976, and they have a high success rate. Proton Therapy works especially well with particular cancers like those in the head and neck. They put the patient in a chair and lower him/her in a huge block of cement where they are bombarded with protons from the accellerator, which kills the tumor. Pretty cool stuff.
The last stop of the tour was the aptly named Main Control Room, where people work in three shifts to monitor the many different experiments that go on 24 hours a day.
The tour was great and highly recommended. The 6800-acre Fermilab site is also home to a large prairie where American Bison graze as well as a bird sanctuary with several lakes. We had a quick look at the Bison (see Amy’s post) and then had a short walk in the birding area.