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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Would a highly degenerate cosmic neutrino background affect fusion reactions that proceed via the weak interaction?
This might seem like a really strange question, but here's my reasoning.
A proton-proton fusion reaction proceeds in two steps:
\begin{align*}
p + p + \text{1.25 MeV} &\rightarrow {}^2_2\mathrm{He}...
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What enabled ignition at the NIF?
The National Ignition Facility
achieved breakeven on December 5th,
obtaining more than 3 MJ from an
input of 2.05 MJ.
What have they been doing differently,
starting this summer?
Laser shots this year ...
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4
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Intermediate product of $\rm CNO$ cycle
$\rm CNO$ 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 free protons - this is a very ...
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What is the shortest duration fusion reaction?
In a tokamak fusion reactor fusing hydrogen nuclei what is the shortest duration experiment that successfully fused nuclei.
Is there a database with fusion reactions and their duration.
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Simulation of plasma in tokamak
I am reading some papers on numerical algorithms for simulation of plasma in the context of nuclear fusion in a tokamak. I am getting a little lost as there is a huge number of references, and it is ...
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Can breeder reactors be used to produce tritium?
I'm just a telecommunications engineer, so my strengths in physics are basically electrodynamics, but recently I have been reading a bit about nuclear physics and nuclear fusion for power production.
...
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1
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Radiative Heat Transfer In Nuclear Fusion
Given the extremely high plasma temperatures that are required to sustain a nuclear fusion reaction in a device such as a tokamak reactor, how can such high temperatures be maintained in the presence ...
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Is the Marx Bank Still the Gold Standard?
Is the Marx bank still the fastest pulse forming network for generating high magnetic fields at large scale, or is there another design that outperforms it?
2
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Theorical efficiency of Chirped Pulse Amplification HB11 fusion reaction
I read that scientists finally reproduced a more efficient fusion with a novel approach.
They accelerate hydrogen inside a pellet with a LASER. A single H atom produces three $\text{He-4}^+$ nuclei.
...
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Why is the D+P fusion reaction not considered for large-scale power production?
I know that D+D (fusion of deuterium + deuterium nuclei) as well as D+T (fusion of deuterium and tritium nuclei) are the reactions most commonly considered for large-scale power production. Why not D+...
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Does a fusor emit dangerous radiation?
I noticed some online videos where people have built these things in their house or garage.
Is it dangerous to do so?
The high voltage appears to be a potential hazard, but what about radiation -- ...
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Usage of rare earth barium copper oxide (ReBCo) superconductors (for fusion reactors)
Recently, scientist from MIT have proposed a new design for a compact fusion reactor, see for example this ArXiV paper.
I do not want to discuss the physics of their reactor but am more interested in ...
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Nuclear fusion ignited by neutron capture
Does anybody know if there was some attempt to make a hydrogen (fusion) bomb using neutrons released from the fission primary?
e.g. using $^{10}\text{B}$ hydrate as a fuel? Assuming reaction
$$^{10}\...
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1
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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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Hollow Conical Shell Z-pinch Lithium Penning Gas For $^6Li$ + $^2H$ => $^4He2$ Fusion?
It occurred to me that boiling $^6Li$ as the thermal step in a Z-pinch device, given lithium's low first-ionization energy, might be a better way of creating homogeneous ions for the subsequent ...
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Muonic Hydrogen Dissociation
Is the dissociation energy of a muonic molecular hydrogen ion the same as an ordinary molecular hydrogen ion? Would the cross-section for dissociation be the same as an ordinary molecular hydrogen ion?...
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Improved estimate of density of free neutrons in solar core
In an answer to this question:
Free neutrons in the sun's core?
I made a very rough attempt to estimate the density of free neutrons in the solar core. There is some non-zero rate for production ...
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Determing for particle density of many particle species in plasma
For quasi-neutrality plasma of many species, the relation of electron density and ion density said that
\begin{equation}
n_{\text{e}} = \sum_{s}Z_{\text{i},s}n_{\text{i},s},
\end{equation}
where $n_{\...
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Theoretical calculation for deuterium tritium fusion
How would a deuterium-tritium fusion feynmann diagram look like in terms of QHD (i.e meson exchange like eta,pi,sigma,omega,...)? I couldn't find anything online whilst this would be quite an ...
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Are there any research mentioning the principle of tornados or maelstroms in plasma physics related to fusion?
There are many different ideas and concepts related to design of fusion reactors and handling plasma confinement, but what about designing one around the principles of a maelstrom or a tornado? Is ...
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Are there any calculations that "backup" magnetized inertial fusion by steam pistons?
Piston driven MTF can generate fusion. General Fusion has released data on the plasma confinement that they do in their machines, so there is no doubt to the feasibility of the approach.
Nonetheless, ...
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1
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Can fusional nuclear compression theoretically be achieved with a unidirectional compressive force?
In other words, is it theoretically possible to get an energy-profittable nuclear fusion reaction by simply slamming compressive force into some nuclei from a single laser compressing from one ...
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1
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1
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A nuclear fusion generating cart
In an unrealistic thought experiment, suppose I had a $100$ meter track with a cart ontop that had a "pocket" on the front of the cart. Suppose further that this track and cart were in a ...
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2
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How does fusion in Tokamak reactors, which produces alpha particles, lead to heating of the plasma?
In a tokamak reactor (toroidal, magnetic confinement chamber), the most common reaction is fusion of Deuterium and Tritium, leading to a production of an alpha particle and neutron with ~3.5 Mev and ~...
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Negative potential energy
In fusion of hydrogen into helium, hydrogen has negative potential energy which adds up and results in a mass defect..
Doubts:-
Why is there negative potential energy between the nucleons in a ...
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0
answers
410
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What is the energy density of Lattice Confinement Fusion?
For quite some time I've seen this video explaining it and this news/article that NASA detected energy from lattice confinement fusion and it always made me quite curious about the actual veracity of ...
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Question about weak decay in p-p fusion
I'm trying to write a very simple simulator of nuclear fusion (with very limited prior knowledge, as I'm finding out), and I'm having a very difficult time understanding p->n conversion.
I believe ...
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2
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Tokamak and Lithium "blankets"
I am working on planning out nuclear fusion for a fictional world, and I am wondering if two ideas are able to work together, or if they contradict each other.
So Dueterium-Tritium fusion releases ...
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Can fusion power production be quickly attenuated/increased, in principle?
Today there was an announcement of a breakthrough in the path toward fusion energy.
This presentation by Michael Shellenberger states that a problem with wind and solar is that, because of ...
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What exactly has the National Ignition Facility recently achieved?
There's been some discussion recently (e.g. in Science) of an NIF yield of 1.35 MJ from a 1.9 MJ input. I think what this means is they've set a record for empirical gain factor of $Q=0.71$. Science ...
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What is "plasma discharge"?
I am trying to find the definition of "plasma discharge"? I searched and only found one useful site (in magnetic confinement fusion research).
But I am still not sure which process this term ...
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Do Efimov states contribute to fusion reactions other than the triple-alpha process?
An Efimov state is a three-body quantum state in which each two-body subsystem is unbound, but the system as a whole is bound because of the large s-wave scattering length. Intuitively, one can ...
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On Nucleus-Nucleus potential for fusion reaction of light nuclei
Its know that in nuclear fusion reactions, the nucleus-nucleus potential cannot be simply given by;
$V(r)=\frac{kZ_pZ_t}{r} for, r>\frac{kZ_pZ_t}{E}$
$V(r)=-U_0 , or, \frac{-U_0}{1+e^{\frac{a-r}{b}...
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Outside grid for fusor
I, for a while now, wanted to build a little Farnsworth desk fusor. Nothing too powerful, simply a small "desk lamp" if you will. As the fusor needs 2 grids, I was wondering, if it might be ...
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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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Released energy during fusion reaction
Click to view the video at required time
According to the video in the link above
the binding energy for deuterium is about 2 MeV and the binding energy for tritium is about 8 MeV so the total for ...
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0
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Can we overcome or mitigate the electrostatic force?
After reading this answer and reading a bit more about fusion, I wondered, is there a way to mitigate the electrostatic force between two nuclei so fusion could take place at lower energies?
For ...
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Why the nuclear fusion 6Li+D and 7Li+P reactions happens 10 time less than H+11B?
The first two reactions generates 2 alphas and the boron one generates 3, but boron has 2 more protons than lithium so should repels more to hydrogen.
I suppose is a question of nuclear states, but ...
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Does a high-velocity ion being neutralized by an electron emit Brehmsstrahlung radiation?
I'm curious about a point of the physics of Polywell electrostatic confinement fusion devices. One of the key claims made in the design is that by confining some "low temperature" electrons to a ...
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Ion acoustic waves in a deuterium plasma?
Has anyone ever experimented with inducing ion acoustic waves in a deuterium plasma? Perhaps to observe the phenomenon of Landau damping? Or to heat the plasma for fusion reactions to occur?
And, ...
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Can stellar nucleosynthesis processes other than deuterium-lithium, i.e., oxygen-burning, take place in a reactor?
It is known that gravitational confinement and supernovae facilitate the synthesis of heavy nuclides; and, that magnetic confinement is thought to facilitate the deuterium-lithium fusion in human-...
user177730
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Logic behind Coulomb explosion fusion?
Many experiments seem to have been done where the experimental setup consists of an extremely short, but intense laser pulse, impinging on e.g. deuterated plastic of some sort or some "jet" of nano ...
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Can air plasma ions in a fusor fuse?
I know that hydrogen ions will fuse in a fusor but what about air ions? Can air plasma ions in a fusor fuse? https://en.wikipedia.org/wiki/Fusor, if so, under what cicumstances, and how would I ...
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Flyback transformer for fusor?
I've always wanted to construct a farnsworth nuclear fusor. I recently ordered a 3-6 volt to 400,000 volt flyback transformer, and was wondering if that could be used in a fusor setup
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Would a charged particle moving through a carbon nanotube experience no or negligible bremsstrahlung?
The context here is for beam-target fusion. The supposition is that it would actually possible to achieve breakeven with an accelerator-based system and cold targets based solely on a modest ...
- 11
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Understanding the concept of cross section
The cross section is a tiny area, measured in barns ($10^{-28} \mathrm{m^2}$), which relates to the probability of a reaction.
But I have trouble interpreting that number.
For example how can I ...
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3
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How do protons fuse in the sun?
I know that Nucelar fusion in the sun requires quantum tunneling to occur, as otherwise the Sun's core wouldn't be hot enough to overcome the Fusion barrier.
However while the 2nd and further stage of ...
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Can you create fusion through scattering?
Could you scatter deuteron molecules (D-D) at high energies into some heavy metal target such that at the time of impact the bond in the deuteron molecule is compressed to such a degree that fusion is ...
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On the units of NRT-dpa electronic losses formula (Lindhard)
I'm trying to convert the PKA energy into damage energy following equation (5) of the NRT-dpa model article. In Fig. 1 you have an example of what you should get. Let's take $E=40keV$ (PKA), therefore ...
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What mass fraction of a main sequence star produces energy?
Only some fraction of the total mass of a main sequence star produces energy in the star's centre through the pp-chains, or in heavy stars, the CNO-cycle. My question is about the mass fraction where ...
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