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Episode 1:
Why fundamental science is important

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For millennia, we have looked up at the stars

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and wondered about the nature of the Universe
and our place in it.

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How big is the Universe?
How old is it?

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What makes the stars shine?

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By performing fundamental research
to answer these questions

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scientists have helped advance
our collective knowledge

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bringing benefits to all of humanity.

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But far from extinguishing our curiosity,

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the answers we find lead to new questions.

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What is the nature of gravity?

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Does the Universe only have
three dimensions of space,

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or are there more to find?

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Why did all the anti-matter
produced in the Big Bang disappear,

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leaving a Universe made of matter?

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What is the origin of mass?

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Here at CERN, physicists from all over the world

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have come together to answer
some of these challenging questions.

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To further our understanding
of the laws that govern the Universe,

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we smash together particles at high energies

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and record what happens
with giant particle detectors

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such as the Compact Muon Solenoid
(or CMS) experiment.

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The Large Hadron Collider accelerates protons

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to nearly the velocity of light

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before colliding them
inside the very heart of CMS.

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The energy of the colliding protons
transforms into matter

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spraying particles in every direction.

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The CMS detector acts as a high-speed camera

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recording collisions 40 million times a second

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for further analysis.

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The LHC is helping us
explore uncharted territory.

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Episode 2:
Conception of LHC/CMS

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The Large Hadron Collider
occupies a 27-kilometre underground ring,

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located around 100 metres below
the Swiss-French border near Geneva.

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It is the most powerful particle accelerator
ever built,

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and is designed to collide protons together
up to 40 million times each second.

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These collisions take place
at four points around the ring.

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At each collision point
sits a large particle detector.

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Each detector is built and operated
by different international collaborations.

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CMS and ATLAS
are the two general-purpose detectors

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designed to observe any signs of new physics
that nature might manifest.

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CMS stands for Compact Muon Solenoid.

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It gets its name from the fact that,
at 15 metres high and 21 metres long,

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it really is quite compact
for all the detector material it contains.

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And it's designed to detect
particles known as muons very accurately;

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and it has the most powerful
solenoid magnet ever made.

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The detector weighs 14,000 tonnes,

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and has around 75 million individual channels

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for detecting and identifying assorted particles.

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CMS is made of several layers,
like a cylindrical onion:

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The innermost sub-detector is the silicon Tracker,

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which registers the trajectories
of charged particles.

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The next layers are
the Electromagnetic Calorimeter

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and the Hadron Calorimeter

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which collectively measure the energies
of electrons, photons

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and composite particles called hadrons.

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Then comes the solenoid magnet itself

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and finally the muon detectors
that make up the outer layers.

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Data from collision events
that are potentially interesting

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are stored for further analysis,

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and the uninteresting ones are discarded.

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Analysis itself is performed around the globe,
using the Worldwide LHC Computing Grid

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that connects thousands of computers
in many countries

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into a single framework.

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CMS has published
over 300 scientific papers so far,

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with 64 petabytes of data collected
and analysed until the beginning of 2013.

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Episode 3:
Construction and operation of CMS

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The CMS experimental site is located
in the French commune of Cessy,

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about 10 km away from CERNâs main campus.

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Excavation of the large underground cavern
that houses the CMS detector began in 1999.

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During early digging on site,
the engineers came across something unexpected:

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the ruins of a Roman villa
dating back to 309 and 315 AD

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with broken coins and pottery.

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The second challenge was expected,

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the diggers would have to get past
an underground flow of water.

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CERN engineers dealt with this
by freezing the water,

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digging through it and applying concrete,

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as they prepared the 100-metre-deep shaft.

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Meanwhile, the CMS detector itself
was being constructed on the surface,

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with parts sent to Cessy from all over the world.

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CMS is designed in slices.

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After construction,
each slice was lowered through the shaft

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into the experimental cavern

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and then assembled on the floor.

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The heaviest slice, weighing 2000 tonnes

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took around ten hours to be lowered
in a very delicate operation

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In 2009, CMS recorded
its first collisions between protons,

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and there were celebrations across the globe.

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On 4 July 2012, CMS announced the discovery
of a new particle to the world,

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now confirmed to be a Higgs boson.

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Physicists continue to search
for many new particles and phenomena

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to resolve the many remaining
unanswered questions.

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Episode 4:
What are the future challenges of CMS?

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Discovering the Higgs boson in 2012
has helped cement our knowledge

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of how fundamental particles
in the entire Universe gain mass.

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This was the first step for the LHC

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and it will take years to study the properties

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of this newly discovered particle.

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The accelerator has been built
with a long-term exploration in mind.

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Our best understanding
of all the particles in the Universe

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and three of the four known forces
that govern them

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is encoded in what is known as
the Standard Model of particle physics.

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However, despite decades of correct prediction
after correct prediction

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physicists know that the Standard Model
does not show us the whole picture.

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Theorists have proposed several extensions
to the Standard Model,

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many of which include predictions
that can be tested at the LHC and CMS.

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These include searches for dark matter
and extra dimensions,

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as well as explanations
of the matter-antimatter asymmetry

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of our Universe.

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The LHC accelerator started a new run in 2015

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at the highest energy ever achieved
by a particle accelerator.

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This new realm is expected
to provide a wealth of new data,

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which CMS scientists
will eagerly analyse for years to come

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in the hopes of unlocking more
of Natureâs most closely guarded secrets.

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The Compact Muon Solenoid will operate
for at least another two decades,

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undergoing a steady evolution over time.

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New sub-detectors are being manufactured,

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existing ones are being upgraded.

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A new scientific journey has just begun

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and we are really looking forward
to continuing this adventure,

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looking at the deepest secret of nature.