a seminar on boson. presentation by Bidhan krushna Mohanta

1. Karanjia Autonomous College,
Karanjia
Educational institution in Karanjia, Odisha
a learning assignment on particle physics
Boson
SUBMITTED BY
BIDHAN KRUSHNA MOHANTA

2. गुरु ब्रम्हा गुरु विष्णू
गुरुुः देिो महेश्वरा
गुरु शाक्षात परब्रम्हा
तस्मै श्री गुरुिे नमुः
Guide - Satyabrata Singh
Dharua

3. welcome everyone to the
part of Mysterious
physics science
PARTICLE PHYSICS
Elementary particles
Stable particles
BOSONS

4. Particle physics (also high
energy physics) is the branch
of physics that studies the nature
of the particles that
constitute matter and radiation.
Although the word "particle"
can refer to various types of
very small objects
(e.g. protons, gas particles,
or even household dust)

5. In 1930 the known elementary particles are the proton, the electron and the
photon.

7. Neutrons
 Chadwick proved the
existence of the
neutron
+
+
+
+
+
++
-
-
-
-
--
-
-
+

8. Elementary
particles
Elementary particles is a particle with no substructure, thus
not composed of other particles.

9. Resonances:
Resonances are those elementary particles which have half live
=10-23 second.
These particles are short lived.
Resonances move with the velocity of
light.
These particles can move about 10-15 meter before
decaying.

10. Stable particles:
These are those elementary
particles which have half live
greater than or equal to 10-16
Stable particles are divided into two
types of bosons and fermions.

11. mysterious science
BOSONS

12. Bosons are the elementary particles which obey Bose-
Einstein’s statistics.
They have a particle spin equal to an integer
that is 1, 2, 3 etc.
Bosons particles are named after
Indian physicist Satyendra Nath
Bose.

13. There are two major types
of bosons:
1. Elementary bosons
2. Composite bosons

14. Elementary
bosons
Graviton
Photon
W BOSONS
Higgs boson
Z BOSONS
Gluon

15. Graviton
A graviton is a hypothetical bosons which is
undetected
• A graviton has zero charge and spin2.
• A spin2 bosons is also called as a tensor boson.
• Gravitons travels with the velocity of light.
Photon
Photon is an elementary boson and is defined as a
discrete bundle of electromagnetic energy.
• A photon has zero rest mass and zero rest energy.
• Photon has no charge.
• It move with the constant velocity of light.
• It have integral spin.
• Antiparticle of photon is photon itself.
• Photons are indistinguishable from one another.

16. W BOSONS W-bosons forms the 3rd type of elementary
bosons
• W-bosons are named after weak force.
• W-bosons have either positive or negative charge.
• The antiparticle of w+ bosons is w- boson.
• W-bosons possess a magnetic moment.
• W-bosons are generally obtained in nuclear decay.
Z BOSONS z-bosons is an example of 4th type
of elementary bosons.
Z-bosons are electrically neutral having no charge.
• The antiparticle of z-boson is z-boson itself.
• The spin of w+, w- and z boson is one.
• W and z bosons are almost 100 times as large as proton.
• Z bosons can’t change the electric charge or any other property
of any particle.

17. Gluon
• Gluon is a fundamental force carriers and is a mediator for strong force.
• Gluon is analogous to the exchange of photons in electromagnetic
interaction between two charged particles.
• Gluon is a vector gauge bosons.
• Gluon does not have electric charge but carry the colour charge.
• The spin of gluon is one.
• There are 8 types of gluon.
Higgs boson
• Higgs boson is another elementary bosons. It is named after Peter Higgs.
• Higgs boson is a quantum excitation of Higgs field which has non-zero
constant value in vacuum• The existence of Higgs boson was confirmed by
data collected at large hadron collider of Geneva.
• The so called god particle is supposed to be building block of the universe.
• Scientist now believe that Higgs boson is the particle that gives all matter
its mass.
• The antiparticle of Higgs boson is Higgs boson itself.

18. Composite
Bosons
MESONS
➢ π mesons
➢ K-mesons
➢ η-mesons
➢ P-mesons
➢ φ-mesons

19. Π-MESONS:
• π-mesons (pions) are the lightest mesons.
• There are three members in the family of pions
that is π+, π- ,π0 .
• All π-mesons are spinless.
Π+-MESONS:
• π+ mesons has a positive charge equal to that of an
electron.
• It has a rest mass of 273 times the mass of an electron.
• The mean life of π+ -meson is 2.55 X 10-8 sec.
Π— MESONS:
• Π- meson has a negative charge and is antiparticle of the
positive π-meson.
• It has same mass, same half life, same mean life as a
positive pion.
Π0-MESONS:
• Π0-meson (Neutral π-meson) has no charge.
• The rest mass of π0 -meson is 264 me.
• The half life of π0 meson is 5.5 X 10-17sec. and its mean life
is 8 X 10-17 sec.

20. K-MESONS:
• There are four members in the family of kappa mesons or Kaons that is K+
mesons, K- meson, neutral kaon and anti-neutral kaon .
K+-MESONS:
• Positive Kaon (K+ meson) has positive charge equal to that of an electron.
• The rest mass of positive kaon is 966 times the mass of electron.
• The half life of positive kaon is 8 X 10-9 sec.
NEGATIVE KAON:
• Negative Kaon (K--meson) is the antiparticle of K+ meson.
• It has a negative charge equal to that of an electron
• Negative kappa meson or negative kaon has same half life as positive
kaon.
NEUTRAL KAON:
• Neutral Kaon (K0) has no charge.
• Its rest mass is 974 times that of an electron.
• The half life of neutral kaon is 7 X 10-17 sec.
ANTI NEUTRAL KAON:
• Anti-neutral Kaon has no charge and is antiparticle of neutral kaon.
• Its half life is 4x10-5 second.

21. ETA-MESONS:
• The eta (n) meson is a boson elementary particle and was discovered in
the collision between pion and nucleon at the Bevatron particle accelerator
by A. Pevsner.
• The mass of eta meson is 1074 times the mass of an electron.
• Eta meson does not carry any charge.
• The mean life of eta meson is less than 10-16 sec.
• The spin of Eta meson is zero.
• The anti-particle of eta meson is eta meson itself.
RHO-MESON:
• Rho meson is a boson elementary particle which has got three members in
its family Just like pions.
• Rho mesons carries the nuclear force within the atomic nucleus.
• Rho mesons are heavier than π-mesons and kaons.
Φ-MESONS:
• Phi meson is another elementary boson which is a vector meson.
• Earlier phi-meson was thought to be pentaquark.
• The antiparticle of phi-meson is phi-meson itself.
• By the collision of electron and positron, phi-mesons are produced.

22. The Large Hadron Collider (LHC)
is the world's largest and most
powerful particle accelerator.
Peter
Higgs
It first started up on 10 September 2008,
and remains the latest addition to
CERN’s accelerator complex.

23. The LHC consists of a 27-kilometre ring of superconducting magnets with a number of
accelerating structures to boost the energy of the particles along the way.
Inside the accelerator, two high-energy particle beams travel at close to the speed of light
before they are made to collide.

24. This requires chilling the magnets to -271.3°C – a
temperature colder than outer space. For this reason, much
of the accelerator is connected to a distribution system of
liquid helium, which cools the magnets, as well as to other
supply services.

25. Finding the Higgs boson, scientists say, will open the door to
the study of other unknowns, like dark matter. Some have
even imagined that, if the Higgs could ever be manipulated, it
could lead to all sorts of science fiction scenarios, like travel
at the speed of light, and more.