"Catch me if you can" - the story of Neutrino hunting

 Part II

The reason behind picking up the neutrino story at first, just because "they have an attitude". They just give a damn to others. But the question is when neutrinos are so reluctant about others why should we care about them, why neutrino matters? So the answer is - if we can catch them, they will reveal to us so many unknown secrets of the Universe. These tiniest particles are fundamental, elementary in nature. That means it cannot be chopped further. The existence of the neutrino was experimentally proved by Fredrick Reines and Clyde Cowan. Before starting the hunting story, let's figure out the motivation of neutrino hunters.

The neutrinos hardly interact with anything and can pass through any matter very easily. This fact leads those hunters to a thought that neutrinos must travel in a straight line for millions and billions of years. So they could be the best storyteller of the universe, as they can carry the information of their source. Neutrinos take birth from various sources such as, from any nuclear reactor, particle accelerator (large hadron collider, at CERN), or maybe from Earth surface due to the presence of radioactive elements and also from our body because of radioactive .decay of potassium. One of the largest sources of neutrinos is our Sun. They are known as solar neutrinos but the highest energetic neutrinos are born in deep space, as the deep space of the Universe is full of violent and mysterious events such as supermassive black holes, supernova explosion, pulsars. So these high energy neutrinos are the messenger of those far reached unknown things of the Universe which bears tantalizing physics mysteries. Scientists immediately understood that there is a sea of possibilities that can be obtained if they can catch them. All the secrets of this Universe lie in the past if we want to uncover them, the neutrino could be the best clue. 

These facts not only excites the particle physicists but also draws the attention of cosmologists and astrophysicists. This is a new way perhaps the best way to look into the secrets of the universe. Scientists thought about a new kind of telescope, known as the neutrino telescope. This ambition lead scientists to the making of the world's largest neutrino observatory in south-pole, named as Icecube neutrino observatory.  Though the project is ambitious, the challenges are enormous. The biggest challenge is to catch the neutrino as they don't interact and can pass through any object.

Ice Cube Neutrino Observatory, South Pole (Antarctica)

A beam of light produced by neutrino

But why the South Pole is chosen as the place for this neutrino observatory? That is also an interesting story. The ice of the South Pole itself acts as a detector in this project. The specialty of the South Pole's ice is- it's the clearest thing available on Earth. The detector is one cubic kilometer in size which is buried under the ice between 1.5 km to 2.5 km. Within this one cubic kilometer volume, there are 5160 light detector sensors have been installed to detect any light source within it. We know when a jet plane travels faster than the speed of sound, it produces a sonic boom behind it. Similarly, when high energetic neutrinos came in contact with ice, it produces a zoo of particles. These particles leave a beam of light behind them which are to be detected by those optical sensors eventually. Does anyone have any idea what is the frequency of detection of those neutrino particles? You may think that it is a joke. But believe me, the possibility is only 10 neutrinos are being detected in a whole year in this project. Don't you think it is a far more thrilling and tiring job than what detectives do? Sometimes I think nothing can be more thrilling and poetic than the neutrino story... Just think these dark particles are carrying messages from the most energetic cosmic engines of our Universe when they finally reach, they left a little bit of light behind them to show their presence. What an insignificant way of presenting the most significant mysteries of the Universe.

Keep an eye for more stories on neutrino hunting and stay amazed...