Questions tagged [fusion]
The fusion tag is used for questions about nuclear fusion, both the basic process at a physical level and it's use as a potential energy source.
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Why is humanity investing so little on fusion research? [closed]
Optimists expect fusion industry to be a reality in 2080 to 2100. Fusion means clean and unlimited amount of energy, it is the fuel of the universe. Fusion will solve most of our time problems ...
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How useful could neutrons as energy directors in fusion (similar to laser-accelerated electrons)
If you directed fast,'hot' neutrons towards a small amount of homogeneously mixed fusion fuel at a point, is fusion likely where the involvement of the neutrons need only be in providing energy and ...
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What can be learned from Wendelstein 7-x experiment?
This experiment achieved a stable plasma for 26 seconds.
What do we learn from it in general(why it was done)? and specifically about the possibility of achieving positive energy flow ($Q>1 $) by ...
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'Forces' enacted by hot neutrons in fusion bomb - Pauli exclusion
Are Pauli exclusion 'forces' on a neutron 100% electromagnetic (Lennard-Jones seems more acute relationship compared to electrostatic force)
If so does that neutrons have two forces between them - '...
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46 views
Can the fusion of deuteron-like nuclei form a new type of periodic table
In late 2019, The Indian Lattice Gauge Theory Initiative, theorized the existence of exotic particles, "which can be formed through the fusion of heavy baryons, similar to the formation of nuclei of ...
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How do we know fusion energies?
Crucial to our understanding of stellar evolution is the energies involved in nuclear fusion reactions.
How do we know those energies? How do we know which fusion reactions take place, at which ...
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47 views
Nuclear Fusion and Quantum Annealing
This is a pie in the sky idea, and a problem finding sort of question that can probably be dismantled easily, but in light of alternative energy needs with climate change, I think it would be ...
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1answer
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Do the MHD equations break down under certain circumstances (and possible connection to fusion experiments)?
The Euler equations produce singularities (in finite time) under certain conditions see here.
When rings of fluid approach each other, in certain simplified scenarios, the Euler equations that ...
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1answer
38 views
Can artificial fusion have the same power density as in Sun's core?
I recently read about solar core, and found that the power density is only 276.5 watts per cubic meter. This seems rather low to me, but on the other hand the Sun is an enormous object, so the total ...
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40 views
Evolution of red dwarf stars
While low mass stars (initial mass approximately $0.1 M_\odot$ to $0.8 M_\odot$) are quite numerous, their evolution seems to draw relatively little attention. The lower central density and ...
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Why do later fusion stages in a star last shorter?
When most of the hydrogen in the core of a massive star has fused to form helium, the next fusion stages (helium, carbon, neon, oxygen, ...) produce less and less energy in a single fusion reaction. ...
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What is the force at play in the emission of neutron out of Helium-5
On nuclear fusion, Wikipedia reads (about Tritium-Deuterium fusion):
The (intermediate) result of the fusion is an unstable 5He nucleus, which immediately ejects a neutron with 14.1 MeV. The recoil ...
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What is the largest obstacle in practical helium-3 fusion? [closed]
I've been busy looking into clean, sustainable energy solutions (for a project)
I ran into He-He fusion of the isotope He-3, and most of it looks more beneficial than the traditional D-T fusion due ...
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Heavy elements creation [duplicate]
Would elements heavier than iron not be extremely rare if only created by supernovae? I believe all elements above hydrogen are created in the star's corona. Hydrogen fusion is not possible in star's ...
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116 views
Spherical Electromagnet Formed By Six Coils For Plasma Containment and Nuclear Fusion [closed]
Several years ago I have proposed an open source spherical magnetic vessel to contain plasma for nuclear fusion which can be seen by following this link.
A photo of it is seen below.
A question here ...
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1answer
52 views
How does binding energy work?
I do not have a very advanced understanding of binding energy and atomic mass but in my classes, I have learned that the atomic mass is equal to the sum of the number of protons and the number of ...
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63 views
Hydrogen bomb without fission stage
The majority of existing nuclear warheads are Thermonuclear devices implementing the Teller--Ulam design. It includes a first stage of "traditional" nuclear fission explosive (Uranium and/or Plutonium)...
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Can another element “burn” at the same rate as hydrogen does in our sun?
From what I understand our sun doesn't actually "burn", instead a nuclear reaction is taking place, which is the cause of heat, light and a electromagnetic radiation. I believe this is called Hydrogen ...
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Why this arrangement of thingys in this light-induced fusion reactor?
Here is a photo from inside a light-induced fusion reactor at the National Ignition Facility, California.
Image source: Wikipedia
I'm not sure what those thingys all around it are but I assume they ...
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Why is this reaction considered a nuclear fusion when the daughter isotope has a nucleus with the same mass?
I understand that in nuclear fusion, the colliding particle unites with the parent and fuses into a single nucleus with a higher mass. Sometimes other small particles
(n, p) are given off.
However, ...
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Fusion in Sun's core [duplicate]
I was reading nuclear physics in which it was mentioned that the coulomb barrier for proton is 400keV corresponding to a temperature of 3 billion Kelvin.I want to know then how does nuclear fusion ...
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2answers
93 views
How does the Sun provide enough energy to fuse protons?
Given that the sun’s temperature is lower than the temperature needed to fuse two protons. How does the sun provide enough energy for this fusion to happen?
Has it do something with tunneling and $E =...
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64 views
Is first light fusion solution possible to work?
This company is running a project with extremely high pressure and low temperature
https://firstlightfusion.com/technology/#our-approach
Their idea is roughly by using a railgun, accelerate a ...
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2answers
67 views
Does fusion only occur with ions?
In nuclear fusion, the particles require enough energy to overcome the Coulomb barrier. The Coulomb barrier is caused by the Coulomb force, which is created by the protons repelling each other because ...
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26 views
Calculation of number of nuclear fusion reaction per cubic meter or kilo
In wikipedia article about Nuclear fusion there is a list of nuclear fusion reaction here.
Is there a equation how to calculate number of nuclear fusion reaction per second per cubic meter or per kg ...
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How would I go about calculating the energy input needed for a cyclotron reactor?
I'm trying to do some math regarding cyclotron reactors. I've figured out how to calculate the radius of a particle's motion in the cyclotron, a rough way to calculate energy output, but I have looked ...
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Is a chain fusion reaction of deuterium oxide (heavy water).possible?
I think it is the case that at very high temperatures that two deuterium atoms can be made to fuse to produce helium and a release of energy. I think under appropriate physical conditions this can ...
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How are thermonuclear weapons possible?
Given the fact that thermonuclear devices are a mix of fission through enriched uranium whose energy initiates the fusion in surrounding deuterium. Question is (how come) fission raises temperature so ...
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3answers
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Energy from fusion beyond iron peak
In the diagram of nuclear binding energy per nucleon Eb/A (vertical axis) and mass number A (horizontal axis), Fe-56 has one of the highest values. Many authors state that nuclear fusion can only ...
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3answers
166 views
Is gravity a factor for sustaining fusion?
Does gravity affect a Fusion reactors ability to sustain a reaction? If so has there been any experiments done or planed for in space?
Holding / maintaining shape might be a lot easier with less ...
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1answer
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Any way to definitively determine the products of deuterium-deuterium fusion?
I was doing some reading and came across these two reactions:
$D + D \rightarrow \:^3He + n + 3.27 MeV$
and:
$D + D \rightarrow \:^3H + H + 4.03 MeV$
(from here: http://hyperphysics.phy-astr.gsu....
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47 views
How is the energy output released in a proton-proton fusion reaction?
$$\rm p + p \to {}^2H + e^+ + v_e$$
The net energy output for this reaction, not including the electron-positron annihilation that likely would occur, is 0.423 MeV - according to my math and sources ...
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Is there a mathematical model for predicting when gamma rays are produced in radioactive decay?
My understanding of gamma ray emission from radioactivity is that the daughter particle is in an excited state, which then produces a gamma ray as the electron drops energy levels. In the case of ...
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Could you use the detonation of a Hydrogen bomb or atomic bomb to start a nuclear fusion reactor [closed]
Would this lead to a reactor that produced more energy than you put in?
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Is high temperature **required** for nuclear fusion?
Tl;dr: Can fusion be achieved only by speeding up particles to high enough speeds to smash into each other?
I know that it is necessary for protons, or any oppositely-charged particles for that ...
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How does the $p+p + e^-\rightarrow D + \gamma\gamma+ \nu$ reaction proceed in the sun?
In this video on nuclear fusion the explanation of the reaction $p+p\rightarrow D + \nu + \gamma\gamma$ is that the two protons collide, form a weakly bound state, and then sometimes decay into the ...
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How To Simulate Muon Induced Nuclear Fusion?
I am familiar with euler-lagrange equations which can be used to simulate a mechanical system, something like an inverted pendulum on a cart. How can I simulate a volume of deuterium and tritium with ...
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Is relativistic channeled electron catalyzed fusion possible?
A few words first about muon catalyzed fusion.
You can see this question sigoldberg1 answer, and this link.
"The muon may bump the electron from one of the hydrogen isotopes. The muon, 207 ...
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NAS report on fast ignition
I'm looking for a paper, or much more likely a small part of a large report, by the National Academy of Sciences from around 2013 on the topic of fusion. The report mentions the fast ignition approach ...
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Has proton-proton fusion ever been seriously considered for an artificial fusion reactor?
All contemporary efforts to perform nuclear fusion as a source of power have focused on reactions between isotopes (often deuterium, tritium, or He3) and/or light elements (often boron or lithium ...
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Ultra Cold Neutrons in a Bottle Question
If you take a large amount of ultracold neutrons and confine them in a bottle would they then decay into protons and then fuse because they are so tightly condensed that the protons, once neutrons, ...
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How do we recover fusion energy from gamma photons
Most fusion reactions create energy in form of hard gamma radiations. A single gamma photon carries energy orders of magnitude higher than any ionization level. Even if we develop some hardcore ...
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Tuning Drifts in Tokamaks
If we managed to make over 50 % of the drifting of the guiding centers of the gyrating particles inside a tokamak to occur into the inwards direction, away from the tokamak walls, would that allow us ...
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Intermediate product of CNO cycle
CNO cycle of stellar nucleosynthesis involves several steps in which different isotopes of Carbon, Nitrogen, and Oxygen are transmuted into each other when hit by a ...
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Why doesn't a deuterium-deuterium reaction usually yield Helium-4?
I assume the above reaction is less energetically favorable than the creation of He-3 (plus a neutron) or tritium plus a proton? But why/how?
Or are the hard, hot, fast collisions too much for it to ...
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Why does fusion above nickel 56 require energy?
I've always struggled with the concept of fission and fusion. I mean I can show a mass deficit with math easily enough but I have always struggled understanding the fundamental concept of why things ...
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Is fission/fusion to iron the most efficient way to convert mass to energy?
Is fission/fusion of any element to iron-56 (or nickel-62?) the best way to convert mass to energy, that doesn't involve black holes?
In other words, will we be always limited to convert only about 1%...
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Is there a “pinch effect” in a Tokamak?
Is there a "pinch effect" in a Tokamak, like in a linear Z-pinch or in a circular pinch (the ZETA machine from the late 50's)? Tokamaks run in a pulsed mode and a powerful circular current is induced ...
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How can corium eating its way into water tanks cause a megaton scale explosion? [duplicate]
The 2019 miniseries "Chernobyl" appears to state that the "lava like" substance of melted radioactive matter from the core, the so-called "corium", could eat its way down into the water reservoirs ...
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How can Sun burn in space?
If there is no oxygen in space how can sun burn in space. (even though I know fire is caused by nuclear reaction inside sun)
