Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
antimatter full report


Antimatter is exactly what you might think it is -- the opposite of normal matter, of which the majority of our universe is made. Until just recently, the presence of antimatter in our universe was considered to be only theoretical. In 1928, British physicist Paul A.M. Dirac revised Einstein's famous equation E=mc2. Dirac said that Einstein didn't consider that the "m" in the equation -- mass -- could have negative properties as well as positive. Dirac's equation (E = + or - mc2) allowed for the existence of anti-particles in our universe. Scientists have since proven that several anti-particles exist.
When antimatter comes into contact with normal matter, these equal but opposite particles collide to produce an explosion emitting pure radiation, which travels out of the point of the explosion at the speed of light. Both particles that created the explosion are completely annihilated, leaving behind other subatomic particles. The explosion that occurs when antimatter and matter interact transfers the entire mass of both objects into energy. Scientists believe that this energy is more powerful than any that can be generated by other propulsion methods.

Antimatter rockets are what the majority of people think about when talking of rockets for the future. This is hardly surprising as it is such an attractive word for the writers of science fiction.
It is, however, not only interesting in the realm of science fiction. Make no mistake; antimatter is real. Small amounts, in the order of nanograms, are produced at special facilities every year. It is also the most expensive substance of Earth; in 1999 the estimated cost for 1 gram of antimatter was about $62.5 trillion.
The reason it is so attractive for propulsion is the energy density that it possesses. Consider that the ideal energy density for chemical reactions is 1 x 107 (10^7) J/kg, for nuclear fission it is 8 x 1013 (10^13) J/kg and for nuclear fusion it is 3 x 1014 (10^14) J/kg, but for the matter-antimatter annihilation it is 9 x 1016 (10^16) J/kg. This is 1010 (10 billion) times that of conventional chemical propellants.
This represents the highest energy release per unit mass of any known reaction in physics. The reason for this is that the annihilation is the complete conversion of matter into energy governed by Einstein's famous equation E=mc2, rather than just the part conversion that occurs in fission and fusion.
Antimatter is exactly what you might think it is -- the opposite of normal matter, of which the majority of our universe is made. Until just recently, the presence of antimatter in our universe was considered to be only theoretical. In 1928, British physicist Paul A.M. Dirac revised Einstein's famous equation E=mc2. Dirac said that Einstein didn't consider that the "m" in the equation -- mass -- could have negative properties as well as positive. Dirac's equation (E = + or - mc2) allowed for the existence of anti-particles in our universe. Scientists have since proven that several anti-particles exist.
These anti-particles are, literally, mirror images of normal matter. Each anti-particle has the same mass as its corresponding particle, but the electrical charges are reversed. Here are some antimatter discoveries of the 20th century:
¢ Positrons - Electrons with a positive instead of negative charge. Discovered by Carl Anderson in 1932, positrons were the first evidence that antimatter existed.
¢ Anti-protons - Protons that have a negative instead of the usual positive charge. In 1955, researchers at the Berkeley Bevatron produced an antiproton.
¢ Anti-atoms - Pairing together positrons and antiprotons, scientists at CERN, the European Organization for Nuclear Research, created the first anti-atom. Nine anti-hydrogen atoms were created, each lasting only 40 nanoseconds. As of 1998, CERN researchers were pushing the production of anti-hydrogen atoms to 2,000 per hour.
Particle Annihilation
When antimatter comes into contact with normal matter, these equal but opposite particles collide to produce an explosion emitting pure radiation, which travels out of the point of the explosion at the speed of light. Both particles that created the explosion are completely annihilated, leaving behind other subatomic particles. The explosion that occurs when antimatter and matter interact transfers the entire mass of both objects into energy. Scientists believe that this energy is more powerful than any that can be generated by other propulsion methods.
The problem with developing antimatter propulsion is that there is a lack of antimatter existing in the universe. If there were equal amounts of matter and antimatter, we would likely see these reactions around us. Since antimatter doesn't exist around us, we don't see the light that would result from it colliding with matter.
It is possible that particles outnumbered anti-particles at the time of the Big Bang. As stated above, the collision of particles and anti-particles destroys both. And because there may have been more particles in the universe to start with, those are all that's left. There may be no naturally-existing anti-particles in our universe today. However, scientists discovered a possible deposit of antimatter near the center of the galaxy in 1977. If that does exist, it would mean that antimatter exists naturally, and the need to make our own antimatter would be eliminated.
There is technology available to create antimatter through the use of high-energy particle colliders, also called "atom smashers." Atom smashers, like CERN, are large tunnels lined with powerful super magnets that circle around to propel atoms at near-light speeds. When an atom is sent through this accelerator, it slams into a target, creating particles. Some of these particles are antiparticles that are separated out by the magnetic field. These high-energy particle accelerators only produce one or two picograms of antiprotons each year. A picogram is a trillionth of a gram. All of the antiprotons produced at CERN in one year would be enough to light a 100-watt electric light bulb for three seconds.
Atom smasher
Antiproton Decelerator (AD)
The Antiproton Decelerator is a very special machine compared to what already exists at CERN and other laboratories around the world. So far, an "antiparticle factory" consisted of a chain of several accelerators, each one performing one of the steps needed to produce antiparticles. The CERN antiproton complex is a very good example of this.
At the end of the 70's CERN built an antiproton source called the Antiproton Accumulator (AA). Its task was to produce and accumulate high-energy antiprotons to feed into the SPS in order to transform it into a "proton-antiproton collider". As soon as antiprotons became available, physicists realized how much could be learned by using them at low energy, so CERN decided to build a new machine: LEAR, the Low Energy Antiproton Ring. Antiprotons accumulated in the AA were extracted, decelerated in the PS and then injected into LEAR for further deceleration. In 1986 a second ring, the Antiproton Collector (AC), was built around the existing AA in order to improve the antiproton production rate by a factor of 10.
The AC is now being transformed into the AD, which will perform all the tasks that the AC, AA, PS and LEAR used to do with antiprotons, i.e. produce, collect, cool, decelerate and eventually extract them to the experiments.
What does the AD consist of
The AD ring is an approximate circle with a circumference of 188 m. It consists of a vacuum pipe surrounded by a long sequence of vacuum pumps, magnets, radio-frequency cavities, high voltage instruments and electronic circuits. Each of these pieces has its specific function:
- Antiprotons circulate inside the vacuum pipe in order to avoid contact with normal matter (like air molecules), and annihilate. The vacuum must be optimal, therefore several vacuum pumps, which extract air, are placed around the pipe.
- Magnets as well are placed all around. There are two types of magnets: the dipoles (which have a North and a South pole, like the well-known horseshoe magnet) serve to change the direction of movement and make sure the particles stay within their circular track. They are also called "bending magnets". Quadrupoles (which have four poles) are used as 'lenses'. These "focusing magnets" make sure that the size of the beam is smaller than the size of the vacuum pipe.
- Magnetic fields can change the direction and size of the beam, but not its energy. To do this you need an electric field: this is provided by radio-frequency cavities that produce high voltages in synchronicity with the rotation of particles around the ring.
- Several other instruments are needed to perform more specific tasks: two cooling systems "squeeze" the beam in size and energy; one injection and one ejection system let the beam in and out of the machine.
How does the AD work
Antiparticles have to be created from energy (remember: E = mc2). This energy is obtained with protons that have been previously accelerated in the PS. These protons are smashed into a block of metal, called a target. We use Copper or Iridium targets mainly because they are easy to cool. Then, the abrupt stopping of such energetic particles releases a huge amount of energy into a small volume, heating it up to such temperatures that matter-antimatter particles are spontaneously created. In about one collision out of a million, an antiproton-proton pair is formed. But given the fact that about 10 trillion protons hit the target (about once per minute), this still makes a good 10 million antiprotons heading towards the AD.
The newly created antiprotons behave like a bunch of wild kids; they are produced almost at the speed of light, but not all of them have exactly the same energy (this is called "energy spread"). Moreover, they run randomly in all directions, also trying to break out 'sideways' ("transverse oscillations"). Bending and focusing magnets make sure they stay on the right track, in the middle of the vacuum pipe, while they begin to race around in the ring.
At each turn, the strong electric fields inside the radio-frequency cavities begin to decelerate the antiprotons. Unfortunately, this deceleration increases the size of their transverse oscillations: if nothing is done to cure that, all antiprotons are lost when they eventually collide with the vacuum pipe. To avoid that, two methods have been invented: 'stochastic' and 'electron cooling'. Stochastic (or 'random') cooling works best at high speeds (around the speed of light, c), and electron cooling works better at low speed (still fast, but only 10-30 % of c). Their goal is to decrease energy spread and transverse oscillations of the antiproton beam.
Finally, when the antiparticles speed is down to about 10% of the speed of light, the antiprotons squeezed group (called a "bunch") is ready to be ejected. One "deceleration cycle" is over: it has lasted about one minute.
A strong 'kicker' magnet is fired in less than a millionth of a second, and at the next turn, all antiprotons are following a new path, which leads them into the beam pipes of the extraction line. There, additional dipole and quadrupole magnets steer the beam into one of the three experiments.
The AD experiments
Three experiments are installed in the Antiproton Decelerator's experimental hall:
ASACUSA:Atomic Spectroscopy and Collisions using Slow Antiprotons
ATHENA:Antihydrogen Production and Precision Experiments and
ATRAP:Cold Antihydrogen for Precise Laser Spectroscopy.
ATHENA and ATRAP's goal is to produce antihydrogen in traps, by combining antiprotons delivered by the AD with positrons emitted by a radioactive source.
Antihydrogen atoms were first observed at CERN in 1995, and later (1997) at Fermilab. In both cases they were produced in flight, that means they moved at nearly the speed of light, i.e. much too fast to allow precise measurements on any of their proprieties! They made unique electrical signals in detectors that destroyed them almost immediately after they formed. Now the idea is to produce slow antihydrogen atoms and store them into "traps", allowing extremely accurate comparisons of the properties of hydrogen and antihydrogen.
ASACUSA, on the other hand, will synthesize "exotic" atoms, in which an electron is replaced by an antiproton. Precise laser spectroscopy of these exotic atoms is expected to reveal lots of information on the behavior of atomic systems.
Antiparticles have either a positive or a negative electrical charge, so they can be stored in what we call a trap which has the appropriate configuration of electrical and magnetic fields to keep them confined in a small place. Of course, this has to be done in good vacuum to avoid collisions with matter particles. Antiatoms are electrically neutral, but they have magnetic proprieties that can be used to keep them in "magnetic bottles".
Portable trap
PET Scan
Particle physicists regularly use collisions between electrons and their antiparticles, positrons, to investigate matter and fundamental forces at high energies. When electron and positron meet, they annihilate, turning into energy which, at high energies, can rematerialize as new particles and antiparticles. This is what happens at machines such as the Large Electron Positron (LEP) collider at CERN.
At low energies, however, the electron-positron annihilations can be put to different uses, for example to reveal the workings of the brain in the technique called Positron Emission Tomography (PET). In PET, the positrons come from the decay of radioactive nuclei incorporated in a special fluid injected into the patient. The positrons then annihilate with electrons in nearby atoms. As the electron and positron are almost at rest when they annihilate, there is not enough annihilation energy to make even the lightest particle and antiparticle (the electron and the positron), so the energy emerges as two gamma rays, which shoot off in opposite directions to conserve momentum.
Antimatter as a propulsion system
This is not some incredible new technology that will power us throughout the galaxy. At the most basic level the antimatter rocket is still a Newtonian rocket, governed by the three laws of motion and it still conforms to Einstein's theory of special relativity, in other words it cannot exceed the speed of light.
Still if we are enable to develop such a propulsion system in the future it will surely render any other Newtonian rocket obsolete overnight, the system has the highest predicted efficiency, specific impulse and probably the highest thrust to weight ratio. There does seem to be a serious amount of disagreement over this last point, the general feeling seems to be that the thrust to weight will at least comparable to today's very powerful chemical rockets.
What this means is that only 100 milligrams (1/10 gram) of antimatter would be needed to match the total propulsive energy of the Space Shuttle (all those huge tanks of fuel!).This fact has led to the interesting observation that future advanced spacecraft, such as the antimatter rocket, will not be designed around their propellant tank like conventional craft. Instead the craft will be designed around the reactors (for nuclear craft) or around the systems and chambers to cause annihilation (for antimatter craft). Radiation shielding will also become a key component of spacecraft design.
Antimatter propulsion systems
Once we have produced and stored the antimatter we can use it in propulsion by releasing it into a chamber and allowing it to annihilate with normal matter which produces its tremendous energy in the form of energetic sub-atomic particles. There are actually two choices for propulsion. Well electron-positron annihilation produces high energy gamma rays which are impossible to control, hence useless for propulsion, and on top of this are potentially very dangerous. Whereas the proton-antiproton annihilation produces charged particles (mostly pions moving at velocities close to that of light) that can be directed with magnetic fields, maximizing propellant mass.
The fact that there is this mass left over after the annihilation means that the full conversion of mass to energy has not occurred as it does in the electron-positron annihilation, therefore slightly less energy has been produced.
This energy, however, still far exceeds any other method and the resulting particles allow this energy to be harnessed by directing it with magnetic forces. In other words the perfect reaction does not produce perfect propulsive result. Another important advantage for antimatter rockets over nuclear rockets is that heavy reactors are not required, the reaction is spontaneous. There are four main designs for an antimatter rocket, they are listed here in increasing specific impulse:
¢ Solid Core - Annihilation occurs inside a solid-core heat exchanger, the reaction superheats hydrogen propellant that is expelled through a nozzle. High efficiency and high thrust, but due to the materials the specific impulse is only 1000secs at best.
¢ Gas Core - Annihilation occurs in the hydrogen propellant. The charged pions are controlled in magnetic fields and superheat the hydrogen; there is some loss in the form of gamma rays that cannot be controlled. specific impulse of 2500secs.

Antimatter Spacecraft
¢ Plasma Core - Annihilation of larger amounts of antimatter in hydrogen to produce a hot plasma. Plasma contained in magnetic fields, again some loss in form of gamma radiation, the plasma is expelled to produce thrust. There are no material constraints here so higher specific impulse is possible (anywhere from 5,000 to 100,000secs).
¢ Beam Core - Direct one to one annihilation, magnetic fields focus the energetic charged pions that are used directly as the exhausted propellant mass. These pions travel close to speed of light so the specific impulse could be greater than 10,000,000secs.
The spacecraft will have to be designed to be very long as the annihilation products travel close to the speed of light.
Journey time
Estimates for travel times to Mars for an advanced antimatter rocket using the beam core approach are anywhere from 24 hours to 2 weeks, it is probable that it will be somewhere in between. Compare this to the space shuttle using its conventional chemical propulsion when a trip to Mars would take between 1 and 2 years.
Over 99.9% of the mass of neutral antimatter is accounted for by antiprotons and antineutrons. Their annihilation with protons and neutrons is a complicated process. A proton-antiproton pair can annihilate into a number of charged and neutral relativistic pions. Neutral pions, in turn, decay almost immediately into gamma rays; charged pions travel a few tens of meters and then decay further into muons and neutrinos. Finally, the muons decay into electrons and more neutrinos. Most of the energy (about 60%) is thus carried away by neutrinos, which have almost no interaction with matter and thus escape into outer space.
The overall structure of energy output from an antimatter bomb is highly dependent on the amount of regular matter in the area surrounding the bomb. If the bomb is shielded by sufficient amounts of matter, the gamma rays are absorbed and the pions slow down before decaying. Part of the kinetic energy is thus transferred to the surrounding atoms, which heat up. In the event of an antimatter detonation in the open atmosphere, most of the energy will ultimately be carried away by the neutrinos, and the remainder by 10-100 MeV gamma rays. The neutrinos would pass through the earth without being attenuated, while gamma rays are relatively weakly absorbed by matter: they lose roughly half of their energy per 500-1000 m of air, compared to only 20 cm of concrete. The explosion would not cause much physical damage because its energy would be evenly dispersed over large area, although the gamma rays may harm people standing nearby. Thus even if the impossible problem of producing enough antimatter were solved, the antimatter bomb would not be as practical or destructive as a conventional nuclear weapon.
About 15 billion years ago, matter and antimatter were created in a gigantic Big Bang in equal amounts, at least according to today's best theory. It is therefore surprising that our Earth, the solar system, and our galaxy (the Milky Way) do not contain any antimatter.
To explain this absence, scientists have come out with two possibilities: either antimatter completely disappeared during the history of universe, or matter and antimatter have been separated from each other to form different regions of the universe.
In the second case, we would be located in a region where only matter exists (or rather what we call 'matter'), but some antimatter coming from an 'anti' region outside our galaxy could still have a chance to reach us. This antimatter would be in the form of anti-nuclei (like anti-Helium, anti-Carbon, etc..) as opposed to lighter antiparticles (such as antiprotons) which are also created in high energy collisions between ordinary matter. To search for this extragalactic antimatter, the best way is to place a particle detector in space.
A worldwide collaboration of physicists, lead by Nobel prize laureate Prof. Samuel Ting of MIT, decided to build the 'Alpha Magnetic Spectrometer', or AMS. AMS is a high-energy particle detector, which will try to detect the passage of such very small amounts of antimatter, while orbiting at an altitude of a few hundred kilometers above the atmosphere.
Some of the main challenges of the project are very technical: having to be carried on the Space Shuttle, each component of the apparatus has to be miniaturized as much as possible to keep the total volume to a maximum of 10 cubic meters and the weight to a maximum of 3 tons (a typical high energy apparatus at LEP with the similar detecting principles is about 1000 cubic meters in volume and 100 tons in weight). Even more important is the power consumption: AMS should not need more than 2 kW (kilowatts) of electricity, provided by the solar panels of the Space Station. And 2kW is less than what a kitchen oven needs!

A first simpler version of the experiment, AMS-01, traveled on the Space Shuttle Discovery for a ten-day mission in 1998. The apparatus consisted of a 6-layer 'silicon microstrip track detector' surrounded by a permanent magnet and a few other systems.
Silicon microstrips can localize the passage of charged particles with a precision of a few hundredth of a millimeter (less than a human hair). The magnet produced a magnetic field where incoming particles were deflected in opposite directions. Nuclei are thus identified by measuring both their mass and charge. During the 10 days that AMS was in space, not a single antinucleus was seen among the 3 million nuclei that traversed the experiment.
In 2004, a new version of the experiment, called AMS-02, will be installed on the International Space Station. AMS-02 will again be searching for any extragalactic antimatter, but this time with more sensitivity, over a longer time period and in a wider energy range.
The new apparatus will be equipped with a superconducting magnet, providing a much higher magnetic field, and an enhanced silicon tracker, able to record billions of tracks of matter (and antimatter) particles. Other detectors have also been added to the design to better identify and measure incoming particles and nuclei. AMS-02 will be installed on the long arm of the ISS and exposed to cosmic rays for three years.
This very moment, a few modules of ISS are already orbiting over our heads. With the experimental data collected during this second mission, AMS hopes to find the last traces of big-bang antimatter, if there are any left!
Problems in Production
We would need at least several milligrams of antimatter to fuel a beam core antimatter engine in local operations and several kilograms for interstellar travel to Alpha Centuri. Given that currently 1-10 nanograms of antiprotons are produced a year at Fermilab (Chicago) and CERN (Geneva), a beamed core engine is not feasible in the near future.
Problems in Storage
The Penning trap has been developed, it is a portable antiproton trap which is capable of storing 1010 (10^10) antiprotons for one week using the superposition of electric and magnetic fields. The next stage is an improvement to 1012 (10^12) antiproton storage. For complete antimatter propulsion it is thought that 1020 (10^20) anti-protons will need to be stored.
¢ What can antimatter be used for
There are several different uses for antimatter, the main one being for medical diagnostics where positrons are used to help identify different diseases with the Positron Emission Tomography (or PET scan). For other uses, we are still in the first phases of development and it's difficult to foresee what will happen in the next ten years.
¢ Can we use antimatter to propel a car or a spaceship
In principle, yes, but in practice it is very difficult. You all know that the Star Trek Spaceship Enterprise flies around powered by antimatter. But in reality, making antimatter is so difficult that it is hard to foresee it ever being used as a propellant fuel. In order to propel a matter spacecraft weighing several tons up to the speed of light, you would need an equal amount of antimatter and, using the present technology, it would take millions and millions of years to produce a sufficient amount. However, if you had a gram of antimatter, you could drive your car for about 100.000 years.
¢ What does antimatter look like
Matter and antimatter are identical. Looking at an object means seeing the photons coming from that object; however, photons come from both matter and antimatter. If there were a distant galaxy made out of antimatter, you couldn't distinguish it from a matter galaxy just by seeing the light from it.
¢ How can you be so sure there is not antimatter around
If there was antimatter here, around us, it would annihilate with matter and we would see light coming out. But we don't...About the possibility of antimatter in space (antistars or antigalaxies), theorist have reasons to believe that the Universe is all made of matter. But we are not 100% sure, and that's way there are experiments, like AMS, which are going to look for it.
¢ If the only difference between a particle and its antiparticle is the charge, how do you distinguish a neutron from an antineutron
Neutrons are made of quarks, and antineutrons are made of antiquarks. Quarks and antiquarks have opposite charges, even though they sum up to zero in both cases. And a very good way to recognize them is to put a neutron close to an antineutron and see how they immediately annihilate.
¢ What about antiphotons
Photons have zero charge and do not contain inside objects that are charged, so a photon can not be distinguished from an antiphoton. Photon and antiphotons are the same thing, i.e. the photon is its own antiparticle.
¢ How do sound waves propagate in antimatter
If there is a difference between matter and antimatter, it is very very tiny, that's why we are doing experiments here at CERN to investigate it. They are so similar that sound waves, that are vibrations of matter or antimatter, would be identical. An antimatter piano would sound exactly as a matter one.
¢ How does the gravitational field act on antimatter
The gravitational force depends from the energy of an object, and since matter and antimatter have both positive energy, gravitation acts on them in the same way. This means that an object made of matter and one made of antimatter would both stand on the floor, the latter one not flying off the sky.
Due to the highest energy release per unit mass of any known reaction ,we can say that antimatter will be a future energy source but first need a reliable method of producing large amount of it.
Cooling: By analogy with the kinetic theory of gases where heat is equivalent to disorder, the term cooling designates the reduction of beamâ„¢s transverse dimensions and energy spread. Different techniques can be used to this effect. Electron cooling, more effective at low energy, uses an electron beam merged with the antiproton beam, and acts as a heat exchanger between the two beams. In the case of stochastic cooling, an error signal generated in a monitor is fed back, via a collector, to the beam sample which created it, eventually centering the sampleâ„¢s characteristics towards the average value, after a large number of passages through the apparatus.
Muon: an elementary particle having a mass 209 times that of the electron, a negative electric charge, and mean lifetime of 2.210-6 seconds.
Neutrino: An electrically neutral particle that is often emitted in the process of radioactive decay of nuclei. Neutrinos are difficult to detect, and their existence was postulated twenty years before the first one was actually discovered in the laboratory. Millions of neutrinos produces by nuclear reactions in the sun pass through your body every second without disturbing any atom.
Pion: it is produced either in a neutral form with a mass 264 times that of an electron and a mean lifetime of 8.410-7 seconds or in a positively or negatively charged form with a mass 273 times that of an electron and a mean life time of 2.610-8 seconds.
Quarks: Subatomic particles which possess a fractional electric charge, and of which protons, neutrons etc. are believed to be composed.
Radio-Frequency or RF: The alternating voltage that provide (or takes) energy to (or from) the beam to accelerate (or decelerate) it.
Specific impulse: It is an important parameter in spacecraft propulsion. It is the thrust produced per unit weight flow rate of the propellant. The unit is in seconds.
Synchrotron: Modern circular accelerator, where the particles are guided by dipole magnets, focused by quadrupole magnets, and accelerated by RF electric fields.
eV: The electron-Volt (eV) is the energy unit which corresponds to the acceleration of a particle having the charge of the electron through a voltage difference of one volt.
LEAR: CERNâ„¢s Low Energy Antiproton Ring, where the first nine atoms of anti- hydrogen were observed.
PS: CERNâ„¢s Proton Synchrotron, which accelerated protons to its nominal energy of 25 GeV for the first time in 1959, it has been upgraded to also accelerate heavy ions, leptons (electrons and positrons), and antiprotons. Its now at the heart of CERNâ„¢s accelerator complex.
LEP: CERNâ„¢s 100 GeV Large Electron-Positron collider, started in 1989, and due to stop at the end of 2000. Its collision energy has now been upgraded to 202 GeV.
¢ Fundamentals of Compressible Flow with Aircraft & Rocket propulsion by S. M. Yahiya


The history of antimatter begins with a young physicist named Paul A.M.Dirac (1902-1984) and the strange implications of a mathematical equation. This British physicist formulated a theory for the motion of the electrons in electric and magnetic fields. Such theories had been formulated before, but what was unique about Dirac’s was that his included the effects of Einstein’s Special Theory of Relativity. This theory was formulated by him in 1928.Mean while he wrote down an equation, which combined quantum theory and special relativity, to describe the behavior of the electron. Dirac’s equation won him a Nobel prize in I 933,but also posed another problem; just at the equation x2 = 4 can have two solutions (x 2, x = -2). So Dirac’s equation would have two solutions, one for an electron with positive energy, and one for an electron with negative energy. This led theory led to a surprising prediction that the electron must have an “antiparticle” having the same mass but a positive electric charge.

1n1932, Carl Anderson observed this new particle experimentally and it was named “positron”. This was the first known example of antimatter. In 1955, the anti proton was produced at the Berkeley Bevatron, and in 1995, scientists created the first anti hydrogen atom at the CERN research facility in Europe by combining the anti proton with a positron Dirac’s equation predicted that all of the fundamental particles in nature must have a corresponding “Antiparticle”. In each case, the masses of the particle and anti particle are identical and other properties are nearly identical. But in all cases, the mathematical signs of some property are reversed. Anti protons, for example have the same mass as a proton, but the opposite electric charge.

Since Dirac’s time, scores of these particle-antiparticle pairings have been observed. Even particles that have no electrical charge such as the neutron have anti particle.

Presented By

Just opposite to the normal MATTER.
Basic components are:
So anti-matter is the mirror image of matter
In 1930, Paul Dirac said that the anti-matter should exist.
In 1932, Carl Anderson discovered positron.
In 1950, physicists at the Lawrence Radiation Laboratory used Bevatron accelarator to produce the anti-matter.
Protons are smashed in high energy particle collider.
Matter-antimatter particles are spontaneously created.
Created from radio active decay.
Created naturally from energy.
Only 1 to 10 nano grams produced in a year.
Most expensive substance on earth.
According to NASA 1 gram cost about $62.5 trillion.
So not economical in using current technology.
Current trap can only store 1010 antiproton for one week.
Next stage an improvement to 1012 antiproton storage.
For complete antimatter propulsion, 1020 antiprotons needed to be stored.
Anti-matter is a fuel source that produce a huge amount of energy.
1 gm of anti-matter can heat 1 kg of water to a temperature of 20000 times of temperature of the core of the sun.
The reaction of 1kg antimatter with 1kg matter produce energy equivalent to 43 megatons TNT.
Energy is produced mainly due to annihilation of matter & anti-matter.
When anti-matter comes contact with normal matter, this equal and opposite charge collide to produce an explosion emitting pure radiation which have very high energy.
Two choice of propulsion
1)Electron-positron annihilation.
produces high energy gamma rays.
impossible to control.
very dangerous.
2)Proton-antiproton annihilation.
produces charged particles.
mass left over after annihilation.
Anti-matter pulse propulsion is a variation of pulse propulsion based upon the injection of anti-matter into the mass of nuclear fuel.
Energy released by that fuel is very higher than any coventional fuels.
FUEL: 100% of the matter and anti-matter is converted into energy which can used as fuel.
MEDICIN: It is used in positron emission tomography.
RESEARCH: Positron annihilation spectroscopy is used in material research.
An anti-matter weapon is a hypothetical device using anti-matter as a power source.
It is more deadly weapon.
There is a lack of anti-matter existing in universe.
Due to the highest energy release per unit mass of any known reaction we can say that antimatter will be a future fuel but need a reliable method of producing large amount of it.

Important Note..!

If you are not satisfied with above reply ,..Please


So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page
Popular Searches: full pdf on antimatter seminar report, packing of particles, egprs gamma, antimatter bomb energy, gamma beta chi, famous educationists in, seminar report on power generation using antimatter***,

Quick Reply
Type your reply to this message here.

Image Verification
Please enter the text contained within the image into the text box below it. This process is used to prevent automated spam bots.
Image Verification
(case insensitive)

Possibly Related Threads...
Thread Author Replies Views Last Post
  TQM Total quality management full report project report tiger 5 11,128 18-09-2016, 08:41 PM
Last Post: velraj
  magnetic refrigeration full report project report tiger 45 38,686 21-07-2015, 03:10 PM
Last Post: seminar report asees
  thermoacoustic refrigeration full report project report tiger 12 17,548 06-03-2015, 06:28 PM
Last Post: Guest
  the gurney flap full report project report tiger 1 2,485 04-12-2014, 02:02 PM
Last Post: pricemuzDet
  exhaust gas recirculation full report project report tiger 8 9,342 05-11-2014, 09:06 PM
Last Post: jaseela123
  IMPROVEMENT OF THERMAL EFFICIENCY BY RECOVERY OF HEAT FROM IC ENGINE EXHAUST full rep project report tiger 7 7,162 18-10-2014, 10:35 PM
Last Post: jaseela123
  reverse engineering full report project report tiger 3 5,457 11-10-2014, 10:49 PM
Last Post: Guest
  sensotronic brake control full report computer science technology 13 21,843 07-10-2014, 10:01 PM
Last Post: seminar report asees
  anti lock braking system full report project report tiger 6 7,122 23-09-2014, 07:25 PM
Last Post: seminar report asees
  DTS-SI ENGINE FULL REPORT seminar class 1 3,496 14-09-2014, 09:11 PM
Last Post: [email protected]