In experiments, researchers found that an 86-microsecond exposure of the beam would bore a hole 40 meters into a block of copper.I see. Maybe this explains why they decided to go with a graphite composite.
...instead of letting it burn a single 1.5-mm-wide hole into the cylinder, CERN engineers designed the system to “scan” the beam onto the face of the cylinder, much as the electron beam is scanned in a cathode-ray-tube television screen...Then let me be the first to say "Where's the oscillator on this thing? I want to watch the other broadcast!"
Finally, it's worth noting that:
Though the graphite beam dump becomes very hot (about 750 °C), it does not melt. In fact, after it cools down it can be reused a few hours later.So they won't have to run down to the spar to get yet another 10-ton graphite cylinder encased in 1000 metric tons of steel and concrete. That there is good planning. Officer thinking, even.
