The Large Hadron Collider… it’s a massive beautiful piece of human ingenuity, engineering
Wait a minute, that’s not the LHC.
This is the Large Hadron Collider.
这 就是大型强子对撞机 缩写LHC
This is the Large Hadron Collider or the LHC for short.
It’s a 27 kilometer particle accelerator
sitting 300 meters under the border of France and Switzerland.
It’s an atom smasher, the biggest in the world.
Designed and built by thousands of engineers, scientists and mathematicians
from across our tiny planet with the goal of
helping other scientists learn about things of
incredibly small size by smashing them together.
These smashings are called collisions.
“This is a really all they’re interested in.
They’re interested in collisions, collisions, collisions.”
That’s Mike Lamont, he’s the Operations Group Leader working on the LHC.
It’s his job to “run beam.”
Beam being nerdy lingo for bunches of hydrogen protons that fill up the LHC.
The LHC is a ring containing two beams going in opposite directions!
But if we look closer
that beam is actually made up of bunches of protons.
In fact,each bunch as about 100 billion protons each.
“These bunches are about 30 centimeters long, typically about a millimeter, dimensions as
they’re going around the ring.
SO,think about a long, thin, tapered, piece of spaghetti.”
Incredibly powerful superconducting magnets keep the beams flying at nearly the speed
of light with the aim of making these proton bunches hit.
“We pass these thin hairs through each other, and we get about 30 collisions.
Most of the protons just miss each other and they carry on around the ring, they come back
one turn later and they can do it again.”
And the reason why they miss each other is because atoms are mostly empty space.
So getting them to collide is incredibly difficult.
It would be like standing 10 kilometers apart and trying to shoot two needle-thin arrows
at each other so they hit halfway.
So, the key is to do this a lot.
“The target this year, to put it in context, is about 800 million collisions a second,
so we really have to work hard to get that rate.”
Hundreds of millions per second is insane!
Imagine trying to control a proton traveling at nearly the speed of light.
To keep the bunches on track, the LHC uses dipole magnets (two magnets).
But, when they need to steer the protons, they use quadrupole magnets(or four)
One on each compass point，applying three to four hundred metric tons of force per meter.
“We take our pieces of spaghetti and focus them down with very strong Quadrupole Magnets,
which are like lenses, to get them down to the diameter of a human hair as we pass them
through each other in the center of the experiments.”
And that’s why the LHC is in the business of collisions.
The LHC is sort of like your power company, but they’re not providing electricity, instead
they’re generating collisions.
More collisions, more better!
They spend all their effort to try and get these bunches of hydrogen ions to hit
inside of other scientists’ experiments.
Of course, having a collision is great, but if a proton collides in the woods and no one’s
there does it make a boson?
Scientists still have to be watching at just the right fraction of a second
to discover a new particle.
That’s where these experiments come in.
They set on the LHC ring at collision points，and they’re probably what you think of when
you hear Large Hadron Collider.
The famous ones are ATLAS and CMS which spotted the famous Higgs-Boson back in 2013.
“it’s called C-M-S Compact Muon Solenoid however it is really not compact.
It’s a relative term, as you can see, nothing of that size is compact.”
塔莉卡·波色博士 此刻正坐在CMS的控制室 等待着
Dr. Talika Bose, sits in the control room of the CMS waiting for an exciting collision
to happen inside her three-storey science experiment, all thanks to the LHC.
“Every twenty five nanoseconds… you have a bunch colliding with another bunch.
假设这有一个质子 那有一个有质子 它们都有核
You may have a proton here and a proton there, which has a heart.
What we call shattering a heart event and out of that come out a whole mess of particles”
This is what she’s talking about.
When two protons collide, it looks like this.
To you and me this may look like a whole mess of particle parts but to Dr. Bose, this ‘mess’
can actually tell you what’s inside a proton.
“There are two important pieces of information that we get from this, one is whether it’s
curving this way or it’s curving that way.
That tell us whether it’s positively charged or negatively charged.
Then how large is the radius of curvature, because it could be curving like this or it
could be curving in a much larger radius and this has a direct relationship with essentially
what the velocity and consequently what the momentum of the particle is.”
And this is why the LHC is awesome.
Dr. Bose is basically watching millions of proton car crashes
in order to reverse-engineer the automobile.
Smashing atoms together can reveal what they’re made of!
物理学家们没有发现注射器 塑料 钢铁和玻璃 而是发现了中子 k中介子
But instead of injectors, plastics, steel and glass, physicists find neutrons, kaons,
pions, muons, and neutrinos.
By the way, physicists call particles are made of these things…
Hence the name LARGE.
Proton collisions like these help physicists reveal exactly what these tiny structures
that make up our universe are made of.
The technology is super advanced, but the science is the same as it’s always been.
We’re simply breaking things apart, hoping to understand how they tick.