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The God Particle

The Universe Is the Answer, What Is the Question?

If God particle is not there, the creation process will not advance further and there will be no life in the Universe.

The particles of matterModel of atom today

Quarks and electrons are fundamental

As far as we can tell no further sub-structure

Proton up up down (uud)Neutron down down up (ddu)All ordinary matter in the Universe is made up from these three particles

Overview In particle physics, elementary particles and forces give rise to the world around us.

Physicist explain the behaviour of these particles and how they interact using the standard model which is a widely accepted framework believed to explain most of the world we see around us.

Particle PhysicsIt is the branch of physics that studies the nature of the particle which are the constituents of matter (particle with mass) and radiation ( massless particle).e.g., Proton, Neutron, Photon

What would the world look like without the Higgs boson ?Yes, You wouldnt recognize the world!!

Without the Higgs boson or something like it giving mass to the basic bulding blocks of matter, electrons would zip about at the speed of light.They wont form

Standard ModelThe Standard Model describes the fundamental particles from which we, and every visible thing in the universe, are made, and the forces acting between them. All the matter that we can see, however, appears to be no more than about 4 percent of the total. A more exotic version of the Higgs particle could be a bridge to understanding the 96 percent of the universe that remains obscure, in the form of dark matter and dark energy.

What is Higgs Field ?The Higgs field is a force field that acts like a giant vat of molasses spread throughout the universe.Most of the known types of particles that travel through it stick to the molasses, which slows them down and makes them heavier.

According to Standard Model a field (Higgs field) is necessary to exist throughout the space and should break the symmetry laws of electroweak interaction.The existence of this field triggers the Higgs mechanism causing the gauge bosons to be massive.

This field exists only for 1trillionth of a second The higgs field is believed to be that its a energy that holds the particles to creates an atom.This field can be created by collision of protons with light speed.

What is Higgs Boson ?The Higgs boson is a particle that helps transmit the mass-giving Higgs field, similar to the way a particle of light, the photon, transmits the electromagnetic field.

Why it is called God particle?The term God particle was coined by American experimental physicist (Nobel Laureate) Leon M. Lederman in his popular science book on particle physics: The God Particle: If the Universe Is the Answer, What Is the Question?

Symmetries and forces:

According to Standard Model the fundamental forces arise from symmetry and are transmitted by particles called gauge bosons. The weak force symmetry should cause its gauge bosons (W and Z boson) to have zero mass but experiments show that the gauge bosons are very massive and short ranged.

Higgs Mechanism It is a mathematical model which was devised by 3 group of physicist (Higgs, Englert and Brout, Guralnik, Hagen and Kibble) almost at the same time to describe why and how gauge bosons could be massive in spite of their symmetry.

They showed that the symmetry would be broken if an unusual type of field exist throughout the space which would enable particles to have mass.

Peter HiggsThe Higgs Boson is named for Peter Higgs who, along with two other teams, proposed the mechanism that suggested such a particle in 1964 and was only one to identify some of its theoretical properties.

Peter HiggsKibble, Hagen and Guralnik (from right to left)

EnglertBrout

PropertiesIt is a boson.Mass = 125.09(+-)0.21(stat)(+-)0.11(syst)Mean Lifetime = 1.56*10-22 secElectric Charge = 0Color charge = 0Spin = 0Parity = positive

What is God particle experiment?According to the theory, a field exists that has non zero strength everywhere even in empty space, and that particle acquire mass by interacting with this so called higgs field.

If this theory is true, a matching particle should also exist and be detectable, providing a crucial test of the theory.

About the ExperimentOne of the primary goals of the Large Hadron Collider at Cern in Geneva, Switzerland, the most powerful particle accelator and one of the most complicated scientific instrument ever built is to test the existence of the Higgs Boson and measure its properties which would allow physicists to confirm this cornerstone of modern theory.

Creating New Particles

positron (e+)

electron (e-)

muon (-)

antimuon (+)E=mc2 !

Back to the particle acceleratorsOne such accelerator was SPEAR a ring which collided electrons and positrons togetherIn 1974 evidence for a fourth quark charm (c) was seen at the SPEAR

In 1975 evidence for a particle like the electron and the muon but much heavier the tau (t)

SIGNIFICANCE Validating the standard model

Explain symmetry breaking

Explain how particles acquire mass

Existence of a scalar field in the universe

THE LARGE HADRON COLLIDER

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THE LARGE HADRON COLLIDER It is the worlds largest and most powerful particle collider built by CERN from 1998 to 2008. It is built in collaboration with 10,000 scientists and engineers. It has a tunnel with 27km in circumference and as deep as 175m (574 ft) beneath the Franco-Swiss border near Geneva Switzerland.

Its synchrotron is made to collide two opposite particle beams of either proton at up to 4TeV or lead nuclei (574TeV per nucleus or 2.76 per nucleon) with energies increased to around 6.5Tev (13TeV collision energy) in 2015. The data is anticipated to be produced at the rate of tens of petabytes per year which is analyzed by a grid based computer network connecting 140 computer centers in 35 countries.

There are 1,232 dipole magnets to keep the beam at circular path and 392 quadrapole magnets to keep the beam focused. Approximately 96 tones of superfluid He-4 is needed to keep the magnets made of copper-clad niobium-titanium at the operating temperature of 1.9K (-271.25C) making it the largest cryogenic facility in the world. The speed of the proton is 3 m/s slower than the speed of light.

DETECTORS IN LHCATLAS (A toroidal LHC apparatus) and CMS (Compact MUON solenoid): They are used for detecting things like new mass and extra dimensionsALICE (A large ion collider experiment): It is built to study a fluid form of matter called quark-gluon plasma that existed shortly after the big-bang. LHCb (Large hadron collider beauty): It is built to study the anti-matter. TOTEM (Total elastic and diffractive crossection measurement): It aims to measure the total crossection, elastic scattering etc.MoEDAL (Monopole and exotic detectors at the LHC): It aims to directly search for magnetic monopole or dyon and other highly ionizing stable massive particles.LHCf (Large Hadron Collider forward): It aims to study the particles in the forward region of collision. It intends to study the energy of neutral pions which can explain the origin of the ultra high energy cosmic rays.30

What are they trying to do in this experiment?

Scientists at the Large Hadron collider, smashed together beams of proton the hearts of tom at close to the speed of light.A

which recreated the conditions that existed a fraction of a second after the Big Bang.

After the collision they rapidly decay.

If Higgs Boson is right then a few Higgs boson should be created in every trillion collisions.

The Large Hadron Collider(LHC)

The Large Hadron Collider (LHC) is the worlds largest and most powerfulparticle accelerator.The LHC was built in collaboration with over 10,000 scientists and engineers from over 100 countries.

Front panel of LHC

Back panel of LHC.The cylindrical tubes shown in the image are Super conducting magnets.

Higgs boson Experiment

When two high-energy particle protons are travelling through a circular loop of distance 27km with a speed of light .These protons rotates around the circuit in clockwise direction and some in anticlockwise direction are made to collide inside the machine .This whole process is observed by the a detector namely ATLAS(detector).By collision the protons are smashed in to tiny particles .This tiny particles are named as QUARKS & LEPTONS.

CMS Assembly

How to get around the 27-km tunnel that houses the LHC ?

Installation of the Silicon tracking detector in the CMS experiment

Proton-Proton Collisions at LHCA typical collision, in yellow, and some of the new particles that result from it, such as photons (in red) from decay of Higgs Boson.

First Steps to Discovery (2011)

CERN shows a CMS proton-proton collision in which four high energy electrons (green lines and red towers) are observed from the decay of a Higgs boson in a 2011 event.

CERN's atom smasher, the Large Hadron Collider, alone cost some $10 billion to build and run.

This includes the salaries of thousands of scientists and support staff around the world who collaborated on the two experiments that independently pursued the Higgs.HOW MUCH DID IT COST?

Result of the experiment -

In July 2012, the scientists at the CERN nuclear research facility found the Higgs Boson, the so called God particle.

The leaders of the experiment said that there were two independent teams who have observed a particle similar to Higgs with mass 126 GeV.

According to the scientists they have more than five sigma certainty that the particle they saw was the Higgs Boson.

THE END