Hey There, Chandra here!
Do you know which experiments are one of the most important in Quantum Physics?
without which, we perhaps wouldn't know much about  the quantum world
Can you Guess?
Well, if you were able to guess it, then that's awesome but if you weren't then it's fine anyways.
The experiment which matters alot in quantum world is scattering or collider experiment.
The first time ganger Marsden Experiment (also known as rutherford experiment), due to which we came to know about Nucleus,
it was also a kind of collider experiment,
In which we were bombarding Alpha Particles on thin gold sheet
Well if you don't know why we did it to Gold, then it doesn't matter,
Gold is the most malleable metal and for this reason we can make it as thin as we want.
And since we wanted the alpha particles to cross the metal sheet so we could observe and study the scattering.
That is why we used gold, so we could have a metal sheet of thickness worth few atoms
Since then, we have come a very long way both in terms of technology and development
and that kind of experiment has become a thing of the past.
Today we have very large particle holders all over the world who can do such experiments with great efficiency
and that too at very high speed.
But why at high speed??!
What will I get by doing such collisions at high speed, which we will not observe in the collisions of slow speed
Something to think about, right?
Well, the answer is very simple
If we are getting two + charged particles to collide at slow speed, obviously because of electric repulsion
they would repel each other even before colliding!
But at high speed not only these particles collide, but due to E = mc², if enough energy is accumulated at a point,
they could also give rise to black holes or other fundamental particles.
And this opens up a possibility of finding new physics.
After all this is how, we had discovered the Higgs
and Hopefully, we will also find signs of Supersymmetry, among other things.
Before running behind those hard and complex ideas
We should have atleast some understanding of how this particle accelerator works.
After all, the machine we use, the environment close to the big bang, this is the energy scale of that level,
we should know how that machine work?
So well, in this video we will do exactly the same thing
So if you are ready to learn the physics of particle accelerator in the world of particle physics with us
make sure to watch the video till the end, let's start.
Well, if you know, the first lightest element in our periodic table is hydrogen,
which consists of one electron and one proton.
Electrons are negatively charged and hence they feel an opposite force due to the electric field,
but the same time protons have positive charge and they feel a force along the electric field.
When we put these hydrogen atoms in the electric field and keep increasing the strength of the field.
So the electric force working on them, which is being felt due to the field, becomes very strong and after a while,
all the electrons are collected on this side of the setup and is separated from all of the protons.
After this we send them to be accelerated by the accelerator.
Maybe, if you are a curious person,
You must be thinking, we had just separated electrons and protons,
so what will happen to the electrons, don't we accelerate them at CERN?
Well, this is a really good question but sadly our CERN is a circular accelerator
i.e. its accelerating setup is in the shape of a circle.
But such a light particle like electron will continue to lose energy in the form of radiation, while obeying Maxwell Equations.
And accelerating them after a particular speed becomes almost impossible.
But there's proton, more massive than electron and losses quite less energy than electron in this circular accelerated motion.
That is why we can use them to achieve higher energy scale at CERN.
After separating the protons from hydrogen atom, we accelerate their speed in several stages.
First, it 's accelerated in LINAC or linear accelerator, which uses an electric field to accelerate.
which is achieved in small radiofrequency cavities made in these accelerators.
In these small chavites, the uniform electric field is maintained, in which the direction of the current varies.
But these oscillations are managed in such a way that the proton is in a particular part of this cavity,
they always feel a force in the forward direction.
and when their energy reaches 50 MeV and they are moving at 31.4% speed of light.
Then they are sent for a few rounds of Proton Synchrotron Boosters or PSB.
PSB is a circular accelerator, so it uses both electric and magnetic fields.
It uses Electric field to accelerate the charges and magnetic field to navigate.
Here the speed of charges is increased by using electric field
and their direction is changed by using magnetic field so they stay inside the PSB.
After this, when our proton has recaptured the energy of 1.4 GeV and is moving at 91.6% speed of light,
we send them to Proton Synchrotron, where its kinetic energy is increased to 26 GeV
and here it attains the 99.93% speed of light.
And then we send it to SPS where it accelerates up to 450 Gev or 99.9998% speed of light.
And then after splitting them, they are sent to the biggest 27KM circumference LHC.
Here, after doing a little bit more accelerating, when they attain the 99.9999991% speed of light
while moving on an energy scale of 4 TAV, they are collided.
But that's not the end.
Now after the collision, the question is to detect these particles,
How do we know what kind of particles have formed after this collision?
and is our original particles still intact?
Well, the answer is provided by particle physics
which studies the interaction of these particles with the matter and force fields.
For example, an electron always moves in a magnetic field on a particular trajectory or path
which depends on its charge and mass,
If we have any other particle which has the same charge as the electron, but abit more massive than electron.
then its trajectory will be different from the electron
and we can use this distinct signature of each particle to detect them.
Something similar happens in CERN's four detectors: CMS, ATLAS, ALICE aur LHCb.
Where we collect and share our data, which on average was 25 million gigabytes per year.
Physicsts study these data and try to make sense of them unravel the deep mysteries of the COSMOS.
All these detectors have their own roles,
CMS and ATLAS built from the focus of the studying Higgs and Higher Dimensions.
ALICE was created to study the state of fluid matter like quark gluon plasma.
And LHCb, well this special because it is made from perspective to solve the missing anti matter mystery of our world.
Well, I hope life gives all of us a chance
so that we can at once see the cool and beautiful accelerators like this with our eyes.
Would you like to go there and see it for yourself??
Do tell us in comment section down below.
See you in the next video, till then stay curious, keep learning, JAI HIND.
