The Large Hadron Collider… it's a massive
beautiful piece of human ingenuity, engineering
and...
Wait a minute, that's not the LHC.
This is the Large Hadron Collider.
Hey everyone, Trace here on location at the
Large Hadron Collider.
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!1 But if we look closer
that beam is actually made up of bunches of
protons...
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.
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: four!9 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?
Who knows.
Scientists still have be watching at just
the right fraction of a second, to discover
a new particle.
Thats where the "experiments" come in.
They sit on the LHC ring at collision points8,
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."
Dr. Talika Bose, sits in the control room
of the CMS waiting for an exciting collision
to happen inside her three-story science experiment,
thanks to the LHC.
"Every twenty five nanoseconds… you have
a bunch colliding with another bunch.
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!
But instead of injectors, plastics, steel
and glass, physicists find neutrons, kaons,
pions, muons, and neutrinos.
By the way, physicists call particles made
of these things…
HADRONS.
Hence the name LARGE.
HADRON.
COLLIDER.
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.
