Sunday, January 11, 2015


CERN is the European Organisation for Nuclear Research (the abbreviation is correct when written in French instead of English). This was another free tour that we took the tram to. However be warned that everyone I talked to was surprised that we could reserve a tour spot the day ahead. Apparently when the weather is nice, it is much harder to secure a tour spot (i.e. book weeks in advance). We lucked out and it was pretty cool.

This is the only tour I've taken notes on. As you can imagine, nuclear research can get complicated. I'll try to relay the most interesting info I understood. If you watch the Big Bang Theory, you may also have heard of CERN and the Large Hadron Collider (LHC). The LHC is the world's largest and most powerful particle collider (like electrons, protons and stuff). It allows them to speed up and crash these particles to see what they're made of and how they react and giving us a little more info on how the world came to be. One recent discovery in 2013 was the Higgs boson. Can't tell you much more than that but it's a big deal :).

So this is one link in a chain of tubes that form a circle underground. It cost CHF$1 million (CHF is Swiss Francs, which is pretty similar to a US dollar).  There are a thousand of these links underground. The actual tube used is inside, is copper and only 20 centimeters in diameter. The rest of the space is used for cooling and regulating the temperature. It takes one month to turn on and turn off (warm up and cool down) the machine. It was not in operation while we were there.

This colorful building houses one (ATLAS) of four detectors where the scientists can actually monitor what happens in those links underground. It is the largest artificial man-made cavern underground to allow for the equipment. 300,000 cubic meters of rock was removed (10.6 million cubic feet or 80 million gallons). The detector is buried 100 meters (328 feet) below ground.  It looks at the momentum and rigidity of particles as well as their charges. The comparison the guide drew to a digital camera helped me. ATLAS is like a digital camera that takes pictures of 100 million megapixels (compared to maybe 8 or 10 megapixels in your camera). It takes 40 million pictures each second. This results in one billion photos per second and one petabyte of data each second. Ever heard of a petabyte? Me either :). It would be equivalent to 250,000 DVDs of data each second. All of this is unfathomable. See the need for notes ;)?

We had a PowerPoint presentation to explain some of this. It was actually quite helpful. Here is the ring that sits underground. It is 27 kilometers long (17 miles). It lies in Switzerland and France and you can see the four detector locations highlighted.

This is a picture of a slice that you could see what happened to the particles, all the zigs and zags.

I mentioned above all the data that is generated each second the detector is working. How do they manage that? A network of computers. More than 1% of worldwide data is at CERN. They created their own computer grid of 200,000 computers to work on one million jobs/tasks each day. It's kind of like their own huge iCloud. You have to be certified before you can use the grid. Data is saved on tapes and managed by robots. One tape can store 5 terabytes of data (I believe that's between a gigabyte and petabyte).

This is a map and list of countries involved at CERN. It employs and takes funding from countries all over the world. 11,000 physicists and engineers are employed each year, one third of which are PhD students.

This was the main operations desk. Lots of computers. Only a few people, I assume because it wasn't really "on". The LHC and this detector took 18 years to complete and parts were supplied from all over the world and assembled at CERN. Part of the movie Angels and Demons was filmed here as well.

This was a neat sculpture outside that has all sorts of science stuff and names engraved over it. I don't understand it but thought it looked cool :).

Viewed from a different angle.

We are entering the old detection area. If you were under 16 and/or pregnant, you couldn't go in. Apparently the remaining radiation is just fine for the rest of us :). This is the location of the first synchrocyclotron (precursor to LHC) in 1957. It was radioactive and required five meters (16 feet) of concrete around it. They have now measured the radioactivity and it is the same amount as what occurs naturally. So safe for tours I guess.

There was a video a light show that explained how it worked but I don't remember and didn't take notes here.

This is a map of the CERN campus. We only visited that dark blue area, so it is quite large. Also, in the middle somewhere is the border with France. They suggest you bring your passport on tours.....just in case ;).

Here's a 3D model of the detector ATLAS so you can see the intricacies of what's inside. There are over 9,000 magnets used to speed up the charged particles. They purchase 120,000 kWh per hour from France.

This is a life size model of the tubes. You see those copper tubes in the black circle in the larger blue tube? That's where the magic happens. The heat created is over 300 degrees. Nitrogen is used to cool the tubes so they don't overheat. 12,000 cubic meters (over 400,000 cubic feet or 3.2 million gallons) is used in the cooling process. When the tubes are cooled, the 27 km ring (17mi) contracts 80 meters (260 feet), so it had to be built to allow for this expansion and contraction while underground. It is pretty amazing to think about.

They had a globe where you could find locations across the world and find out their part in CERN. If you're from northern IL, you've probably heard of Fermilab, which has their underground ring, albeit on a smaller scale.

These are some bird's eye views of where the ring is.

This is an example of the shared computing across the world. 

An intense but awesome place to visit!

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