Nuclear Fusion

Hot fusion refers to the process of creating energy by fusing together atomic nuclei at extremely high temperatures, usually in the range of millions of degrees Celsius. This process is what powers the sun and other stars, and is a focus of research as a potential future energy source on Earth.

Variable yield, colloquially known as dial-a-yield, works by modifying a variety of factors which adjust the strength of the nuclear (or thermonuclear) explosion.

Most modern nuclear weapons are boosted weapons which contain a hollow-pit. There is a tank with some quantity of deuterium / tritium gas mixture which is injected into the hollow pit to increase the yield of the primary before detonation. The amount of gas can be adjusted, increasing or decreasing the yield of the primary.

Also, the timing, duration and intensity of the neutron beam fired into the core upon compression of the primary, can be adjusted as well, which can also affect the yield of the primary detonation.

Another proposed method involves firing the primary at such a low yield, preventing a fusion reaction from starting in the weapon's secondary. There may also be a means to control the amount of radiation or plasma sent to the secondary by means of the interstage assembly to allow the secondary to ignite (or not).

In earlier weapons, sometimes the secondary was removed, or the primary was augmented with rings of fissile material around the primary, which would have increased the amount of fissile material in the weapons. These adjustments would have been done when the weapon was assembled, producing the various types of mods where one weapon in the same class would have a significantly different yield than another weapon sharing the same pit, explosive package, etc.

The primary issue is one of containment.

In order to initiate a nuclear fusion reaction, you need to strip away the electron shells of the atoms, and you need to move the nuclei close enough together for the attractive strong interaction to overcome the repulsive electromagnetic interaction. Stripping away the electron shells, i.e. creating a plasma, requires ultra high temperatures. Moving the nuclei close enough together requires ultra high pressures.

Problem: We have nothing that can maintain and/or contain this temperature and pressure. No currently known material can do this. The stars do it easily, because of gravity, but a reactor large enough to take advantage of gravity would be much larger than the Earth. Not even Jupiter is large enough, though some say it is close.

So, we are left with alternative forms of containment.

One possibility is magnetic containment. Problem is, in order to do that, we need superconducting magnets, so we are faced with having ultra cold components in close proximity to ultra hot components. That, to say the least, is technologically difficult. Presently, the ITER, a tokamak design, is being constructed in Cadarache, France to attempt this. Timeline is set for first testing in 2019, with first fusion in 2026. Note, however, that we are only talking 500 MW of power, and then, only for 480 seconds. All this at a projected cost of 15 billion euros.

Another possibility is inertial containment. This is how the hydrogen bomb works, but that is an uncontrolled, destructive reaction. The NIF, a laser implosion device, has been constructed in Livermore, California (USA). It generates 4MJ pulses that can theoretically induce 45MJ fusion pulses. Problem is, that it takes 422MJ to charge the system's capacitors, so the total energy curve is backwards, and the system heats up so much that cooldown is required after each firing - they are attempting to be able to do 5 firings a day - hardly any kind of continuous output. As a result, this is only an experimental facility, though so is the ITER, described above.

Best guess - we will not achieve controlled fusion power for at least 100 years. Even the projected goals for the next 50 years do not include any kind of sustainable reaction, let alone any kind of commercial deployment.

Asian fusion refers to a style of cuisine that combines elements from various Asian culinary traditions. It often involves blending flavors, techniques, and ingredients from different Asian regions to create innovative and unique dishes.

In fusion, there needs to enough energy to overcome the Coulomb forces of the particles you are trying to fuse, and get the particles close enough that nuclear attraction takes over. This is the short answer.

Hydrogen and oxygen. On the sun two hydrogen atoms and one oxygen atom are fused at the core which keeps the suns light going and giving it more energy. The result of this is water. H2( hydrogen 2 ) O( oxygen ) h2o

Fusion is when a force causes the nuclei of two atoms to merge together. Say, for instance, two hydrogen atoms (each containing a single proton in their nucleus) are near each other. Normally, they give great resistance to being put too close. However, a force (most likely incredible heat) manages to force their nuclei together. They become a single nucleus, containing two protons. It now has the structure of helium, and is considered to be it.

Nuclear fusion is the fusion of two nuclei (atoms) which, when combined, form a highly unstable element or isotope, which almost immediately breaks up, producing energy and more, smaller nuclei to continue this chain reaction. The energy given of can be harnassed as heat to heat water into steam to turn a turbine to produce electricity, in which case the reaction would be controled, or it can be allowed to go out of control, in which case it would produce a massive explosion.

Nuclear fusion and fission are both processes that involve releasing energy from the nucleus of an atom. They can both produce large amounts of energy and are used in nuclear power plants.

There is currently no evidence to suggest that a hydrogen bomb has been used in Afghanistan. The conflict in Afghanistan is primarily fought using conventional weapons such as firearms, explosives, and missiles. The use of a hydrogen bomb would have widespread and devastating consequences far beyond the immediate area of conflict.

Fusion reactors are very much safer because-- 1) They can't "run away" 2) They leave few radioactive products when worn out. 3) They have no radioactive spent fuel. 4) They don't become dangerous if anything fails, they just stop.

Yes, nuclear fusion is the process by which the sun produces energy through the fusion of hydrogen atoms into helium. This process releases vast amounts of energy in the form of light and heat, making it the most plausible explanation for the source of solar energy.

Smaller nuclei fuse to become larger ones.

The sun is mostly hydrogen and helium. This is how stars start out. They make energy by squeezing the hydrogen nuclei together till they stick:

- two simple hydrogen (H1) nuclei (protons) get stuck into a Deuterium (H2) nucleus. One proton turns into a neutron by absorbing a nearby electron (the two atoms each had an electron to start with but see below).

- the Deuterium nucleus gets another proton stuck onto it and becomes either Tritium (H3) or Helium 3 (He3). Another proton will make it He4 which is regular helium. (or maybe H4 or Li4 but they decay into He4. He4 fills out the inner orbital so it's really stable.)

- and so on and so on. As a star gets older, it starts having more He and Li and Be and heavier elements from this process. If there's enough helium or Lithium, they'll start fusing with each other and make even bigger nuclei, faster.

At each step, energy comes off because it's in a lower energy state - like magnets that are stuck together instead of apart - but in the case of nuclei, it's the Protons that attract the Neutrons and vice versa, thru The Strong Force. But at the same time, all the protons are repelling each other! They're both + charged! Also, if they're cold atoms like you find on earth, they each have electron shells 100,000 times bigger than the nucleus, like a sand particle being suspended in the middle of a big balloon, so two neighboring atoms never get close enough to fuse.

To make it stick together, you have to get the protons and neutrons close enough for The Strong Force to kick in and overwhelm the proton-proton repulsion. Fortunately in the sun, it's so hot (the atoms and atom pieces are flying around so fast) that the electrons have been totally ripped off their nuclei and fly around free with the nuclei - that's called a Plasma. If two protons or other nuclei manage to stumble into each other hard enough, they'll fuse.

As time goes on, heavier and heavier nuclei form. Unfortunately these reactions require more compression and heat. Gravity is still working, so the nuclei keep fusing. the biggest the nuclei become is around where Iron is on the list of elements. At that point, there's no energy coming off at all- it's sortof an energy valley and this is the lowest point. The star becomes a white dwarf, or explodes as a supernova and the core becomes a neutron star or black hole, depending on how big it is.

Heavier nuclei are made either when the star explodes as a supernova, or by a process in red giant stars. The sun is too small for either of these two to happen. The heavy elements on earth are assumed to come from some other supernova like 5 billion years ago.

The Sun carries out nuclear fusion at its core, where hydrogen atoms combine to form helium, releasing energy in the process. This energy pushes outward, counteracting the Sun's own gravity. As the core fuses hydrogen into helium, the core contracts and the outer layers expand, leading to the Sun bloating outward.

Planets do not naturally generate nuclear fusion. Nuclear fusion occurs in stars, where the extreme heat and pressure at the core allows hydrogen nuclei to merge and form helium, releasing energy in the process. Planets lack the conditions necessary for sustained nuclear fusion reactions.

Nuclear fusion reactions occur in the core of stars, including the Sun, where high pressure and temperature conditions allow hydrogen atoms to combine and release a tremendous amount of energy. Scientists are also working on creating controlled nuclear fusion in experimental reactors on Earth as a potential source of sustainable energy.

In general, nuclear fusion produces a new atom (or, in some cases, two atoms), a change in the amount of heat present and possibly some other emission. The specific products of nuclear fusion depend on what is being fused.

The fusion of 2H + 2H produces 3H + a proton + 4.02 MeV

The fusion of 2H + 3H produces 4He + a neutron + 17.6 MeV

The fusion of 6Li + 2H can produce 4He + 4He + 22.4 MeV

In the cases where fusion produces atoms heavier than iron, the reaction is endothermic, consuming heat rather than producing it.

Yes, nuclear fusion is a potential source of energy that has not yet been fully developed for practical use. It involves combining two light atomic nuclei to form a heavier nucleus, releasing a large amount of energy in the process. Scientists are working on harnessing fusion as a cleaner and more sustainable alternative to nuclear fission and fossil fuels.

It hasn't been achieved yet, and it seems doubtful that it is possible. You may want to read the Wikipedia article on cold fusion to get a more detailed overview.

To summarize it: the muon-catalyzed kind definitely is possible and is routinely done by researchers in the field - the problem is that it requires more energy to generate the muons than you can get out of the fusion. The Fleischmann and Pons kind appears to have been poor laboratory technique (I'm being charitable here, and not suggesting that it was deliberate fraud).

In nuclear fusion, lighter atomic nuclei combine to form a heavier nucleus, releasing energy in the process. Since the total mass of the products is less than the sum of the masses of the initial nuclei (due to the released energy according to Einstein's mass-energy equivalence, E=mc^2), the mass per nucleon decreases after fusion.

Nuclear fusion takes place only in the core of the Sun, or any star. Extremely high energy (temperatures) are required to force atomic nuclei together. The fusion reaction releases heat energy, which continues the fusion of other nuclei.

So far, only one reactor has successfully produced more energy than was expended, and that one is in California. But 23 countries currently have experimental reactors: USA, Canada, China, Japan, Australia, India, Iran, Kazakhstan, Pakistan, South Korea, the European Union, the Czech Republic, Spain, France, Germany, Italy, Netherlands, Portugal, Russia, Switzerland, UK, Ukraine, and Sweden.

The only place in which nuclear FUSION takes place is in stars (the sun included), and in the detonation of a hyndrogen bomb. If you are asking about nuclear FISSION (an entirely different process), restate the question.