

How the Large Hadron Collider proton beam is turned off - mhb
http://www.spectrum.ieee.org/aug08/6558

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dmpayton
_In experiments, researchers found that an 86-microsecond exposure of the beam
would bore a hole 40 meters into a block of copper._

Simply. Amazing.

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angstrom
True, but due to copper's heat conducting properties I would think it would be
the worst thing you could put in the beam's path (next to your hand).

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rms
<http://cosmicvariance.com/2008/08/04/what-will-the-lhc-find/>

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DarkShikari
Gordon Freeman, you must reach the control room and turn off the proton beam!

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mechanical_fish
"I built the gluon gun, but I've never been able to use it on a living soul!"

(I may be paraphrasing. It's been years since I heard that line delivered, and
it was probably 2am at the time.)

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ars
Hmm, aren't they also making hydrocarbons?

The protons become hydrogen, and have to go somewhere - does it bubble off? Or
does it react with the carbon and become hydrocarbons - or are there simply so
few protons that it doesn't matter?

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mechanical_fish
The article refers to beams of "hundreds of trillions of protons". That's
very, very few in chemistry terms. Ten hundred trillion (which is the upper
limit of the number which that phrase could be talking about) is 10^15.
Avogadro's number is 6 x 10^23. So we're talking about 1.6 billionths of a
mole of protons.

Let's assume that all turns into hydrogen -- that's as good a hypothesis as
any. While randomly Googling for the value of the ideal gas constant (the R in
PV=nRT; I note in passing that Google has rendered my prized copy of the _CRC
Handbook_ obsolete in a flash) I found the even handier sentence:

 _The molar volume of any gas at STP is known to be 22.414 L/mol_

Which implies that we'll make about 4x10^(-5) milliliters of hydrogen at STP.
About enough to fill a cube 330 microns on a side. And that's if we turn them
into a _gas_ , which isn't exactly dense.

The moral of this story is that statistical mechanics deals with _very large
numbers of particles_. The second moral is that it's not the current in the
proton beam that will kill you. It's the voltage, aka the energy of the
protons. Which is not surprising -- if you want to simulate the Big Bang, you
need a lot of bang.

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abstractbill
I love reading about ridiculously large-scale engineering. Here's another,
along similar lines: <http://jwz.livejournal.com/94645.html>

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lpgauth
Can't wait for this experiment to start.

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zandorg
That's a big pencil!

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jraines
By Chuck Norris?

