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21 views

Do exotic states of matter have high fusion cross-sections?

The Lawson criterion suggests that a chain fusion reaction will only occur in a confined plasma. Since it's a product of temperature and pressure (or density) a chain reaction would be virtually ...
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2answers
57 views

How is hydrogen stored in hydrogen bombs?

Fusion bombs obviously fuse hydrogen atoms, using the pressure from a fission bomb. But how much hydrogen does it contain, and how is it stored? AFAIK hydrogen easily drops its electron and escapes as ...
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2answers
26 views

How much energy is released per unit mass from depressurizing degenerate matter?

A neutron star remnant consists mostly of neutron degenerate matter. If you happened to suddenly have 1 kg of it in your lap without the pressure necessary to keep it degenerate, I suppose it would ...
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0answers
25 views

Aplications of algebraic topology/pure mathematics in nuclear fusion

I am planning on working on an independent research class this fall at a community college. My instructor wants to focus it around pure mathematics/topology/homotopy. I think she has done a phd in ...
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0answers
26 views

If a $\lambda$ (inverse units of distance) is given as a description of a spheromak, what is $\lambda$ referring to? [closed]

For a magnetized Marshall gun that generates spheromaks, the paper [1] says "the aspect ratio is 4.4, and the minimum $\lambda$ is 9 $m^{-1}$." What is $\lambda$ likely to be referring to? [1] ...
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0answers
35 views

Help identifying a Fusion approach

Several years ago, I saw a Google video (back before the YouTube acquisition) where the leader of a group studying an unusual approach to fusion gave a presentation. His approach centered on a ...
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1answer
34 views

Why do practical fusion reactions need more than one product?

The Wikipedia article about nuclear fusion says that To be a useful energy source, a fusion reaction must ... have two or more products: This allows simultaneous conservation of energy and ...
2
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3answers
585 views

Pure hydrogen star

What is the smallest mass of pure hydrogen that can ignite fusion? That is can population III stars have tiny masses? How would such stars develop? How long would such a star last?
2
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1answer
51 views

Using particle accelerators for nuclear fusion [duplicate]

Apologies this is probably a stupid idea but I am curious and my knowledge of physics is limited as I am 14. So I was wondering if we could use particle accelerators to achieve nuclear fusion. I have ...
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1answer
27 views

Plot of fusion energy output growth? [closed]

What would a chart of energy output of elements of mass X fused with hydrogen look like? What about X fused with X?
4
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1answer
68 views

Free neutrons in the sun's core?

In the standard description of proton-proton fusion, the first step of the interaction proceeds through the unbound diproton $\rm^2He$: $$ \begin{aligned} \rm p + p &\to \rm {}^2He^* \\ \rm ^2He^* ...
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4answers
223 views

Coupling fission and fusion and disappear all mass. Why doesn't this happen?

I'm confused about the fact that in a fission process the masses of the "products" are less than the mass of the "reactants". And in a fusion process the masses of the "products" are less than the ...
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3answers
111 views

Why do only heavy radioactive elements perform fission or fusion?

Why do only heavy radioactive elements perform fission or fusion? I mean what's so special about heavy elements which makes them ideal for nuclear fission? Also why do only neutrons show ...
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2answers
97 views

If planet like Jupiter is massive enough to hold hydrogen with its gravity is it bound to become a star?

I have been reading about Jupiter as of late and reason I am asking is if Jupiter has strong enough gravity to pull hydrogen to itself then it should be only matter of time when it will acquire enough ...
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0answers
59 views

Difference between fusion plasma and fluorescent lamp plasmas

How is the plasma in a compact fluorescent lamp (CFL) different from a plasma in say ITER or the sun? Why does ITER need 100MK and a CFL can work at practically room temperature (apart from the ...
1
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1answer
71 views

Are fusors a cost-effective source of helium?

It's not hard to imagine geology that didn't give us convenient concentrations of terrestrial helium, or that someday soon we'll have exhausted those natural sources. How cost-effective is existing ...
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2answers
159 views

Why more Fe-56 than Ni-62 as fusion product in heavy stars?

Suppose we create an Fe-56 nucleus and an Ni-62 nucleus, each from individual protons and neutrons. In the case of Ni-62, more mass per nucleon is converted to binding energy. Thus we could argue the ...
3
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1answer
52 views

Solar Power Fusion

Would it be possible through a clever arrangement of solar dishes, lenses and mirrors etc, to create fusion at the focal point? Imagine you arrange your solar dishes, lenses and mirrors in such a ...
3
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0answers
51 views

How large should an optically large fusion reactor be?

This is just theoretical consideration. I expect that size of the reactor would be impractical to build on Earth, but I'm interested how much. EDIT: perhaps it could be good for some huge spacecraft ...
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1answer
48 views

What is an element's “weight” when talking about “elements heavier than iron” being formed in supernovae

I always hear that elements heavier than iron are formed in supernovae. But, what is taken as an element's weight? I had always believed that this meant any elements with an atomic number greater than ...
1
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1answer
143 views

Hydrogen-boron fusion

Recently I found out that Hydrogen-1 and Boron-11 together are considered a viable nuclear fuel. Fusion of Hydrogen-1 and Boron-11 produces three highly energetic Helium-4 nuclei. Basically the entire ...
12
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1answer
2k views

Is an H bomb a better “fusion reactor” than the Sun's core?

A few days ago I asked about a fusion reactor design I was thinking about and got a well-founded answer by #BowlOfRed#. There is the question I posted: Another cold-fusion reactor scheme :) Is it ...
3
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0answers
77 views

nuclear fusion scaling with reactor size

Thinking about physics of thermonuclear fusion, I have always intuitive sense, that making fusion feasible is matter of reactor size. In other words I feel like: if the fusion reactor is big enough ...
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1answer
103 views

A possible way to initiate a nuclear fusion reaction without a nuclear fission trigger [closed]

A few years back I read in either Popular Science or Popular Mechanics about a new kind of high explosive that had an energy density many times higher than the most potent ones previously developed, ...
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3answers
506 views

Could the LHC be used for fusion experiments? [duplicate]

Just looking at the beam energy and peak power for the LHC, 360 MJ and petawatts, respectively, dumped in about 100 ┬Ás, would this be sufficient to do useful fusion experiments?
0
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1answer
27 views

Is there any difference between fusing and smashing particles?

Fusion reaction In fusion process, a condition is required to allow the process to take place. Temperature (energy) + close contact (overcome coulomb barrier). The process normally observed inside of ...
0
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1answer
55 views

Have scientists always known that the Sun was not a fuel+air system?

Astronomy is far older than nuclear physics. So there was a long time in which fire was a reasonable explanation for the sun burning. Has any scientist figured out the sun cannot possibly be a normal ...
0
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1answer
26 views

Electric Field inorder for Fusion to occur

If I want to do D-D -> He + n fusion in an electric field - what potential would I need? So I know the coulomb barrier is at $U=k^2 \frac{e^2}{10^{-15}} = 1.44 MeV$ This is when the strong force ...
4
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1answer
61 views

PP Chain and CNO cycle relationship

At what temperature would the energy generation rates of the PP-Chain and CNO cycles be roughly equivalent? The dependences are so vastly different that I am wondering how and by what equations they ...
0
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0answers
70 views

Effective Coulomb barrier for deuteron

What is the effective Coulomb barrier for a Deuterium-deuterium fusion reaction? I am seeing temperatures of about $40 \times 10^7 K$ online, but have no idea how they are getting this. If we have ...
2
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1answer
62 views

Why is there such an interest in Helium-3 and Moon mining?

A simple Google search reveals dozens of articles about the clean fusion energy that can be obtained from Helium-3. As Helium-3 is highly scarce on Earth, there are many spectacular schemes for ...
0
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2answers
57 views

Is there a difference in the energy output of a nuclear fission reaction as opposed to fusion?

For example, if I split a Helium atom will I get the same amount of energy as when I fuse Hydrogen into Helium? If there is a difference, what will be the difference (in general not according to ...
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0answers
110 views

Fusion - A List of Experimentally Achieved Beta Numbers in Magnetic Confinement [closed]

I want a list of all the beta numbers achieved in across all magnetic fusion energy devices. This is not theory, but the actual number measured experimentally. No list like this exists. The beta ...
5
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3answers
254 views

Why does fusion stop at iron when nickel is most tightly bound?

My understanding is that stellar fusion naturally stops at iron because it is energetically unfavourable to grow the nucleus further. But iron is only the third most tightly-bound nucleus, nickel is ...
5
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1answer
230 views

What types of fusion reactions happened in population III stars?

I have read that, in smaller stars, such as our Sun, the fusion reaction that takes place is a proton-proton chain, or PP chain for short. From what I have learned, in larger stars, a different ...
2
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3answers
186 views

Does energy conservation not hold in fission and fusion processes?

I have read that during fission and fusion processes, there is some kind of equilibrium between the single nucleus and the disintegration products, so they are constantly being converted into each ...
2
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0answers
54 views

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 ...
2
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1answer
81 views

How much potential fusion energy is in Earth's ocean?

Assuming the most efficient manner for extraction, and a ready supply of other necessary materials not mentioned herein, and given the current estimates about the volume of Earth's ocean, how much ...
1
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1answer
46 views

What makes red giants big? [duplicate]

I read some about red giants and so far I understand red giants become exhausted of burning hydrogen in the core, so then start hydrogen burning at shell and may or may not be burning helium in the ...
0
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0answers
60 views

Could deuterium saturated palladium capsules be used for inertial confinement fusion?

NIF(National Ignition Facility at the Lawrence Livermore National Laboratory in California) uses the ICF (inertial confinement fusion) approach in order to harvest fusion energy. At NIF, indirect ...
4
votes
1answer
186 views

Chemical and stellar evolution in stars

I'm having an exam soon where I have to discuss/describe the follow figure: It's the first figure I have to explain, and it was on the same slide as the one below, so I'm thinking they are somewhat ...
4
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2answers
142 views

What is the main thermal energy source for a protostar, the contraction or the deuterium burning energy?

According to the virial theorem, when a protostar contracts, half of the gravitational potential energy is radiated and half is kept as kinetic energy of the falling material which in turn heats the ...
2
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1answer
97 views

Water behaviour under theoretical near-infinite pressure conditions

I've asked a similar question here but the answer given shows the behaviour of water under general conditions. I'd like to know what the behaviour of water is like as pressures increase towards ...
2
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1answer
74 views

Questions regarding the feasibility of “Jupiter”-like fusion reactor

I was reading this post from this website: Turning Jupiter into a star It basically talks about whether fusion can or does happen in the core of Jupiter. I know Jupiter cannot become a star, but I ...
0
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1answer
32 views

Proton 'Laser' ? could we get a laser-like effect? [closed]

This is a speculative question. question: Can we gain protons, by smashing a high speed proton into a hydrogen plasma? Background: I was thinking about how lasers repeatedly send the photons thru ...
0
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0answers
46 views

Fusion plasma compression with liquid metal

General Fusion plans to use an imploding shockwave of molten lead to compress a magnetized plasma "spheromak" target in order to make it burn more efficiently. How come the lead does not quench the ...
0
votes
1answer
108 views

Fusion reactors why does size matter?

I've been following articles about fusion recently, and with the ITER project mostly. I have noticed that their view point is they need to build a large scale reactor in order to achieve their goals. ...
4
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0answers
178 views

Are Lockheed Martin nuclear fusion claims realistic? [duplicate]

Lockheed Martin reported breakthroughs on nuclear fusion technology for energy. Are these claims scientifically realistic? The claims have been reported in the media: ...
6
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1answer
977 views

Can the High beta fusion reactor work?

Are the claims made about the http://en.wikipedia.org/wiki/High_beta_fusion_reactor realistic? Can such a small fusion reactor really work?
2
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1answer
86 views

Why is plasma confinement on the NIF called inertial confinement when it appears to be confined by pressure?

I've heard that unlike Tokamaks that use magnetic confinement of the plasma, the NIF project uses 'inertial' confinement. What's inertial about it? Do they spin the plasma to use angular momentum like ...