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ABSTRACT

The Large Hadron Collider is the world’s largest and the highest-energy particle accelerator .The LHC lies in a 27 km tunnel in circumference beneath Franco- Swiss border near Geneva, Switzerland. It was built by European Organisation of Nuclear Research (CERN) in order to produce very high energy particle collisions .
This synchrotron is designed to collide opposing particle beams of either protons at an energy of 7 TeraElectronVolts (or 1.12 microjoules) per particle, or lead nuclei at an energy of 574 TeV (or 92.0 μJ) per nucleus.
The LHC became the world's highest-energy particle accelerator on 30 November 2009, achieving a world record 1.18 TeV per beam and surpassing the record previously held by the Tevatron at Fermilab in Batavia, Illinois.
Scientists hope that the LHC will help answer many of the most fundamental questions in science: Will the collider either demonstrate or rule out the existence of the elusive Higgs Boson(s), completing (or refuting) the Standard Model? , What is the nature of the Dark Matter which appears to account for 23% of the mass of the Universe? What is the origin of mass? Why do tiny particles weigh the amount they do? Why do some particles have no mass at all?


INTRODUCTION

"Particle physics is the unbelievable in pursuit of the unimaginable. To pinpoint the smallest fragments of the universe you have to build the biggest machine in the world. To recreate the first millionths of a second of creation you have to focus energy on an awesome scale."
The Large Hadron Collider (LHC) is the world's largest and highest-energy particle accelerator .It is a gigantic scientific instrument which lies in a tunnel 27 kilometres in circumference, as much as 175 metres beneath the Franco-Swiss border near Geneva, Switzerland This Synchrotron is used by physicists to study the smallest known particles – the fundamental building blocks of all things. It will revolutionise our understanding, from the minuscule world deep within atoms to the vastness of the Universe.
The Large Hadron Collider was built by the European Organization for Nuclear Research (CERN) with the intention of testing various predictions of high-energy physics, including the existence of the hypothesized Higgs boson and of the large family of new particles predicted by supersymmetry. It is funded by and built in collaboration with over 10,000 scientists and engineers from over 100 countries as well as hundreds of universities and laboratories.
Two beams of subatomic particles called 'hadrons' – either protons or lead ions – will travel in opposite directions inside the circular accelerator, gaining energy with every lap. Physicists will use the LHC to recreate the conditions just after the Big Bang, by colliding the two beams head-on at very high energy. People sometimes refer to recreating the Big Bang, but this is misleading. What they actually mean is:
•recreating the conditions and energies that existed shortly after the start of
the Big Bang, not the moment at which the Big Bang started
•recreating conditions on a microscale, not on the same scale as the original
Big Bang and

LARGE HADRON COLLIDER
•recreating energies that are continually being produced naturally (by high
energy cosmic rays hitting the earth’s atmosphere) but at will and inside
sophisticated detectors that track what is happening
No Big Bang – so no possibility of creating a new Universe.
On 10 September 2008, the proton beams were successfully circulated in the main ring of the LHC for the first time,but nine days later, operations were halted due to a serious fault between two superconducting bending magnets. Repairing the resulting damage and installing additional safety features took over a year.
On 20 November 2009, the proton beams were successfully circulated again, with the first proton–proton collisions being recorded three days later at the injection energy of 450 GeV per beam. The LHC became the world's highest-energy particle accelerator on 30 November 2009, achieving a world record 1.18 TeV per beam and surpassing the record previously held by the Tevatron at Fermilab in Batavia, Illinois.
After the 2009 winter shutdown, the LHC was restarted and the beam was ramped up to 3.5 TeV per beam, half its designed energy, which is planned for after its 2012 shutdown. On 30 March 2010, the first planned collisions took place between two 3.5 TeV beams, which set a new world record for the highest-energy manmade particle collisions

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