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The Boson is supposed to be the basis of everything in existence. From the debris of colliding particles will also emerge the answer to one of our oldest questions: how did the universe begin?
The second time around, it may prove more fortuitous. In June 2008, before visiting CERN, or the European organisation for nuclear research, and while camping in Divonne, a charming little French village about 20 km from the world’s largest and most ambitious accelerator centre in Europe, this is what I wrote: One can hear the soft beat of a contemporary tune played out somewhere in the valley, as church bells toll in the distant background of an otherwise tranquil village, and the mighty Alps appear almost serene with anticipation of the large hadron collider humming into operation.
On September 10, protons in the collider started circling around in the underground tunnel from ‘a large ion collider experiment’ or Alice detector, and travelling at 99.999991 per cent of the speed of light they went around the tunnel 11,245 times per second with about six hundred collisions taking place every second, building up massive energy. And then the experiment had to be shut down, because of a leak of liquid helium which cools its giant magnets.
Some said that the experiment was doomed from the beginning. Others stated that the $8 billion tag was too large. A few felt it was a challenge thrown at God. But the 10,000 scientists from 100 countries who collaborated on the project, said the wait would be worth it, to solve a 30-year-old puzzle: does the Higgs particle exist?
The sub-atomic world is an esoteric one. The particle is supposed to explain the origin of mass in the universe, and is said to be behind the mysterious ‘dark matter’ that astronomers say exists in the galaxies. The elementary particles which build up the nucleus of an atom, the building block of all matter, consists of neutrons and protons bound together by mesons. The incredible temperature attained after the collision of two nuclei — a million times more than the temperature at the interior of the sun — simply melts the particles, dissolving them into a plasma of their interior inhabitants, the quarks which are glued together by gluons.
However incredible it may seem, the universe in its first few moments after the Big Bang also consisted of a plasma of quarks and gluons. The underground mini-bang aims to capture the primordial moments of the very creation of the universe.
To accelerate the particles, huge superconducting magnets are needed, which are cooled down to minus 271 degree centigrade or just 1.9 degree above absolute zero — a feat which can be achieved with the most developed form of cryogenics. Almost 12 million litres of liquid nitrogen will be vapourised during the initial cooling down period and over 700,000 litres of liquid helium would be used in the process. The collider is the most power-hungry machine ever made and the temprature inside is lower than the coldest part of our universe.
CERN came into being as Europe was coming out of the ravages of World War II, and when some of its visionaries decided to build an accelerator complex to look at the deepest and darkest mystery of nature. They foresaw that the effort would create a surge in technology unmatched anywhere else, thus putting Europe on the road to rapid recovery.
The United Kingdom, France, Germany, Italy and other European countries took the leading role in raising funds, even borrowing them from the US. The vision paid off. The law that unites electromagnetism and the central force of radioactivity were discovered at CERN. The earlier discoveries in fundamental particles led to the invention of the web system of computing, now known as the world wide web.
By 1984, Carlo Rubbia and Simon van der Meer of CERN got the Nobel Prize for their contribution to accelerator physics. To Rubbia goes the credit for the large hadron collider. It took scientists 15 years to build, with contributions from the European Union and several countries, including India. In the beginning, India was represented by one person. But by the 1980s, there was a paradigm shift.
A group led by the late P K Malhotra of the Tata Institute of Fundamental Research joined the CERN effort. Scientists from the Variable Energy Cyclotron Centre in Kolkata, Institute of Physics in Bhubaneswar, IIT-Bombay and those in the universities of Rajasthan, Jammu and Punjab in Chandigarh collected together to design and build the photon multiplicity detector, funded by the department of science and technology and the department of atomic energy. This would form part of the collider.
In India, a project of this size had never been attempted before. Physicists at the Saha Institute of Nuclear Physics, designed and fabricated an original chip, called Manas, and about one lakh of these are hanging in the muon arm detector of Alice. The Institute also built one of the muon arms in collaboration with the Aligarh Muslim University.
The work was won by the Indians against tough competition. The Institute of Physics has been participating in Alice since the beginning and has contributed to all aspects of designing, fabrication, testing, installation and commissioning of the photon multiplicity detector. India scientists have also contributed to simulation studies and software development for data analysis.
The Raja Ramanna Centre of Advanced Technology has contributed $40 million worth of superconducting steering magnet jacks on which the beam lines stand. By the 1990s, India had became a key player on the world scientific stage and ceased to be a spectator. The Brookhaven National Laboratory in the US invited India scientists to participate in the Star detector to look for photons in the debris left by the heavy ion collider.
There are three great beasts of detectors at the large hadron collider — Alice, cryogenic muon spectrometer, or CMS, and ‘A Torroidal LHC Apparatus’ or Atlas, each costing over a billion dollars. Among the debris of colliding sub-atomic particles, these monstrous machines will be sifting for evidence to answer the most fundament questions of science. And our workhorses, the photon multiplicity detector and the Manas chips will help them search for the answers in the primordial plasma.
In a world where wars, poverty and global crises scar the lives of many, the beauty and aesthetics of an idea called CERN is like a pole star guiding our soul to a wonderful world, in a beautiful universe. And we are discovering it all over again.
