Nuclear fusion is the fusing of atoms, thus causing a great release of energy. This is what powers (albeit somewhat partially, due to the fact that a fission bomb is needed to start the reaction) fusion bombs (thermonuclear) and the sun. Nuclear fusion as to reactors is being researched around the globe, and results are expected mostly in 2050 or so. It is being researched mainly at the Large Helical Device in Japan and the Tokamak Reactor in the US.

Most fusion research is directed at toroidal fusion, which uses supercooled superconducting magnets to hold a plasma in the shape of a torus inside a giant stainless steel reactor vessel while it is heated with microwaves. If the magnets can keep the plasma in shape long enough, the reaction will become self-sustaining.

As all the writeups thus far have been directed towards magnetic confinement fusion reactors, I feel I must mention the possibility of inertial confinement. Basically, you stick a fuel pellet in a target chamber and fire lasers or ion beams at it from all directions. The pressure from the beams both initiates fusion and confines the plasma. Neat, huh? Only thing is, most people (myself included) are convinced that this method is impractical for power generation, and that research in this vein is, rather, a weapons program. But hey, that's fine with me. I just think the NOVA laser is increfibly cool.

There is also a third option, often called Inertial Elctrostatic Confinement fusion, first proposed by Philo Farnsworth. In IEC, a space charge is generated at the center of a symmetrical configuration with accelerates and focuses fusion fuel ions to collide in the center of the space charge. More information on this concept can be found under fusor.

This is a highly subjective term paper placed into the public domain (this means here: author unknown) I am not to blame for incorrect information given (I do doubt that this is completely correct.) I am posting this for the overall humor of the paper, not the factual information provided.

Why nuclear fusion is so cool.......

For a fusion reaction to take place, the nuclei, which are positively charged, must have enough kinetic energy to overcome their electrostatic force of repulsion. This can occur either when one nucleus is accelerated to high energies by an accelerating device, or when the energies of both nuclei are raised by the application of very high temperature. The latter method, referred to the application of thermonuclear fusion, is the source of a lot of really cool energy. Enough energy is produced in thermonuclear fusion to suck the paint of 1 city block of houses and give all of the residents permanent orange afros. The sun is a example of thermonuclear fusion in nature. If I was an atom, I could only wish to be in a thermonuclear reaction. Thermonuclear reactions occur when a proton is accelerated and collides with another proton and then the two protons fuse, forming a deuterium nucleus which has a proton, neutrino and lots of energy. I have no idea what a deuterium nucleus is, but is must be 10 times cooler than just a regular nucleus. Such a reaction is not self sustaining because the released energy is not readily imparted to other nuclei. thermonuclear fusion of deuterium and tritium will produce a helium nucleus and an energetic neutron that can help sustain further fusion. This is the basic principal of the hydrogen bomb which employs a brief, controlled thermonuclear fusion reaction. This was also how the car in the Back to the Future movie worked. It had a much more sophisticated system of producing a fusion reaction from things like, old coffee grounds, bananas, and old beer cans. Thermonuclear reactions depend on high energies, and the possibility of a low-temperature nuclear fusion has generally been discounted. Little does the scientific community know about my experiments. I have produced cold fusion in my basement with things like: stale bread, milk, peanut butter and flat Pepsi. I have been able to produce a ten-megaton reaction which as little as a saltine cracker and some grass clippings. But enough about my discoveries. Early in 1989 two electrochemists startled the scientific world by claiming to achieve a room-temperature fusion in a simple laboratory. They had little proof to back up their discovery, and were not credited with their so-called accomplishment. The two scientists were Stanley Pons of the university of Utah and Martin Fleischmann of the University of Southampton in England. They described their experiment as involving platinum electrodes an electrochemical cell in which palladium and platinum were immersed in heavy water. These two losers said that the cell produced more heat than could be accounted for. Yeah right!! The week before I was talking to both men on the phone and I told them about all of the cool things you could do with platinum. I said "Now Martin, what you need to do is get your hands on some platinum and some heavy Mexican drinking water. The amount of chemicals in the Mexican drinking water is sure to cause a violent reaction with the platinum electrodes and produce lots of energy. I have been doing this sort of things in my basement for years." When I told him that though that NASA could power their shuttles with this sort of a reaction, he nearly wet his pants. Now as usual, I received no credit for MY discovery, but that is ok..I have grown used to it. I taught Einstein, Newton, and Ron Popeel (inventor of things like the pasto-matic, hair-in-a-can, and the pocket fisherman) everything they know. Besides, the two schmucks didn’t even follow my instructions for the experiment. However, until I reveal my secrets about cold fusion, it will remain only a proposed theory.

Nuclear fusion is also what powers the rest of the stars in the solar system. Stars carry out fusion in a thermonuclear manner. Thermonuclear is a really cool word which I am going to use several more times just because it is so cool. In a thermonuclear reaction matter is forced to exist in only in a plasma state, consisting of electrons, positive ions and very few neutral atoms. Fusion reactions that occur within a plasma serve to heat it further, because the portion of the reaction product is transferred to the bulk of the plasma through collisions. In the deuterium-tritium reaction the positively charged helium nucleus carries 3.5 MeV. The neutron escaped the plasma with little interaction and , in a reaction, could deposit its 14.1 MeV in a surrounding lithium blanket. I have know idea what that last sentence meant, but I am going to memorize it, because I will sound super smart if I tell someone about the neutrons activity in a plasma thermonuclear reaction. The neutrons activity would breed tritium and also heat as a exchange medium which could be used to produce steam to turn generator turbines. However, the plasma also loses thermal energy though a variety of processes: conduction, convection, and bremsstrachlng which is electromagnetic radiation about 1000 times stronger than the microwave in your kitchen.

Bermsstrachlng is the electromagnetic energy which is produced by the deceleration of a charged particle. Energy also escapes in the reaction through line radiation from electrons undergoing level transitions in heavier impurities, and through losses of hot nuclei that capture an election and escape and confining field. Ignition occurs when the energy deposited within the plasma by fusion reactions equals or exceeds the energy being lost. In order to achieve ignition, plasma must be combined and heated. Obviously, a plasma at millions of degrees is not comparable with an ordinary confining wall, but the effect of this incompatibility is not the destruction of the wall as might be expected.

I have found that if one uses Corning Ware in a microwave set on high, plasma can take place quite safely. It is important to note that tupperware is not suited well for thermonuclear reactions, and is best left to use to store weapons grade plutonium in. I find that the air tight lids work simply splendidly in keeping all of that nasty glowing radioactive dust to a minimum in my room.. Although the temperature of a thermonuclear plasma is very high and the power flowing through it may be quite large the stored energy is relatively small and would quickly be radiated away by impurities if the plasma touched a wall and began to vaporize it. A thermonuclear plasma is thus self-limiting, because any significant contact with the vessel housing causes it’s extinction within a few thousandths of a second. Therefore, plasma must be carefully housed and handled while it is occurring.

Most of the research dealing with fusion since 1950 has used magnetic fields to contain the charged particles that constitute a plasma. The density required in magnetic-confinement fusion is much lower than atmospheric density, so the plasma vessel is evacuated and them filled with the hydrogen-isotope fuel at 0.0000000. What is the deal with all of those zeros? I mean it means the same as 0..It must be one of those wacky science thingys. Sort of like why inflammable and flammable mean the same thing. Who knows. Anyway, Magnetic-field configurations fall into two typed: open and closed. Wow, that was real obvious. In an open configuration, the charged particles, which are spiraling along magnetic field lines maintained by a solenoid, are reflected at each end of a cell by stronger magnetic fields. I have found in my research that if one used a 9-volt battery (preferably from an old smoke detector) the reaction takes place much more efficiently. In this simplest type of mirror machine, many particles that have most of their velocity parallel to the solenoidal magnetic field are not reflected and can escape. This is a real problem for me when ever I try to perform a thermonuclear fission reaction. I have yet to find a solution to the problem, but for now stale Trident chewing gum works as a acceptable improvision for the problem. Present day mirror machines retard this loss by using additional cells to set up electrostatic potentials that help confine the hot ions within the central solenoidal field.

In a Closed reaction, the magnetic-field lines along which charged particles move are continuous within the plasma. This closure has most commonly taken the form of a toros, or doughnut shape, and the most common example is the tokamak. In a tokamak the primary confining field is totoidal and is produced by coils of surrounding the vacuum vessel. Other coils cause current to flow through the plasma by induction. This toroidally flowing current wraps itself around the plasma. Is it just me, or are there a lot of really useless big words. I mean, totoidally, what is this? My only thought is that is one of those many wacky science terms that people who you see on the Discovery Channel would use. The poloidal magnetic field, at right angles, that stronger toroidal field, acting together, yield magnetic field lines that spiral around the torus. This spiring ensures that a particle spends equal amounts of time above and below the totoidal midplane, thus canceling the effects of a vertical drift that occurs because magnetic field is stronger on the inside of the torus than on the outside.

Another cool thing about thermonuclear plasma is that a certain type of plasma called Tokamak plasma can be heated to temperatures of 10-15 million k by the current flowing in the plasma. Imagine how quick one could broil chicken. In less than ½ seconds, you could have a perfectly golden brown and tender chicken ready for dinner. At higher temperature the plasma resistance becomes too low for this method to be effective, and heating is accomplished by injecting beams of very energetic neural particles into the plasma. These ionize, become trapped, and transfer their energy to the build plasma through collisions. Alternatively, radio frequency waves are launched into the plasma at frequencies that resonate with various periodic particle motions. The waves give energy to these resonant particles, which then transfer it to the rest of the plasma through collisions. In some of my most recent expirations I have been able to use radio frequency waves to push electrons around the tokamak to maintain the plasma current. Such noninductive current drive allows the tokamak pulse to outlast the time limitly imposed by the fact that , in a transformer-driven tokmak reaction thingy, the plasma current lasts only as long as the current in the secondary coils reach their current limits, confinement is lost, and the plasma terminates until the transformer can be reset. Although the plasma in as inductively driven tokamak is pulsed, the electricity produced would not ve, because the thermal inertia of the neutron-capturing blanket would sustain stream generation between pulses. By allowing longer pulse or steady-state plasma operation, however, radio frequency current drive could lessen the thermal stresses in the fusion reaction. However, so far cooking with plasma has not been to practical for me.

Another approach to fusion pusued since about 1974, is termed inertial confinement. During my many patrols during the Viet..-NAM war, I further developed my theory’s and opinions regarding inertial confinement fusion. When I arrived home with a severely hyper-extended earlobe, I was in great pain and suffering, but I still managed to explain my findings to the scientific community. Essentially, my theory of inertial confinement fusion works similar to how the atomic bomb works. A small pellet of frozen deuterium and tritium are compressed to a very high temperature and densities in a process analogous to what is accomplished by bombarding the pellet from all sides, simultaneously with a really intense laser. I nearly put my eye out with the thing. It is certainty not a toy.

Anyway, back to fusion. After you have nuked the pellet thing with the super laser thingy, the pellet vaporizes and, by mechanical reaction, imparts inwardly directed momentum to their remaining pellet core. The inertia of the inwardly driven pellet material must be sufficient to localize the power of -9 seconds required to get significant energy release. In 1988, after my defeat in the presidential election, I helped the government preform underground tests in the Nevada desert. I had showed the government how to do this type of experiment in 1986, but it took them two years before they could get it right. I think that their chief nuclear engineers name was Forrest or something..Man what a idiot. He just could not get it right. Once again, people took credit for my discovery. The miniminum confinement condition necessary to achieve energy gain in a deuterium-tritium plasma is that of the product of the density in ions per cubic cm and energy containment time in seconds must exceed 6x10 -13th power. This was attained for the first time in a hydrogen plasma at the Massachusetts Institute of Technology in 1983. The temperature required to ignite a fusion reactor is in the range of 100-250 million k, several times the temperature of the center of the sun. What? How can you have a reaction several times the suns central temperature in a enclosed plasma environment? Is this some kind of wacky scientist joke or something? Anyway, the science geeks at M.I.T supposedly did produce this kind of fusion.

The goal on fusion is in effect, to produce and hold a small star. It is a daunting and tedious research which is considered to be of the most advanced in the world. Creating a small dwarf star in a man-made environment has thought to be the highest scientific challenge. Even though last weekend my little brother and I did create several dwarf stars, we were forced to put them out because the neighbors kept complaining about the light. The cop was a real jerk. I tried explaining to him what I was doing, but he kept asking me to do stupid things like: stand on 1 leg and recite the alphabet backwards, and touch my nose with my finger. Apparently the cop though that I was getting smart with him when I started to explain to him about the beauty of fission energy. Oh well, at least he didn’t arrest me..again...

[Editor's note, 9/28/2006: Erm. Assuming the author considered it as fiction, I simply fixed a link and added a few <p></p> tags so that the writeup wouldn't be quite so headache-inducing.]

Various forms of nuclear fusion take place within the stars, and without them there would be no life as we know it.

Stars on the main sequence radiate energy by the fusion of protons, which can be thought of as hydrogen nuclei. This is known as hydrogen burning, and ultimately it provides the energy by which humans live.

First, two protons are fused together to form a deuterium nucleus - a proton and a neutron. The creation of a neutron from a proton entails the release of a positron (an anti-electron) and a neutrino, a massless, chargeless particle. The nuclear equation can be represented as follows: note that the numbers in subscript represent charge and the numbers in superscript mass, and that both are preserved in all the following reactions.

11H+ + 11H+ ----> 12H+ + ν + 10e+.

Two particles of charge 1+ and mass 1 (protons) have been transformed to a particle of charge 1+ and mass 2 (a deuterium nucleus), a massless, chargeless neutrino, and a positron of charge 1+.

This deuterium nucleus then fuses with another proton to produce a helium-3 nucleus:

11H+ + 12H+ ----> 23He2+

Finally, two of these helium-3 nuclei fuse together to form a helium-4 nucleus (the common isotope of helium) and release two protons:

23He2+ + 23He2+ ----> 24He2+ + 11H+ + 11H+

This reaction releases energy for the same reason as all nuclear reactions - helium has a higher binding energy per nucleon than hydrogen, so energy is released equal to the difference in binding energies of the reactants and products.

Later in a star's life, while it is in the red giant phase, the core temperature becomes great enough (around 100 million degrees Celsius) to ignite further nuclear fusion reactions. First, beryllium (Be) is created from helium. Then carbon (C) is created from helium and beryllium. Finally, oxygen (O) is created from carbon and helium. These reactions are exothermic (they release energy), and thus they are spontaneous in the sense that they will continue unaided as soon as enough energy has been provided. However the activation energy in this case is too great for the reactions to occur in a main sequence star, so it does not occur until the red giant phase.

Stars which become supernovas release so much energy that they initiate endothermic fusion reactions: those whose products are actually less stable than the reactants. These reactions are responsible for all the elements heavier than iron-56, which has the highest binding energy per nucleon of any possible nucleus. Without supernovas, there would be no nickel, copper, zinc, silver, gold, iodine, platinum, lead, mercury, uranium or plutonium, to name some of the most familiar.

Source: Bryan Milner, Cosmology (OCR), 2000

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