Does radio-carbon dating disprove evolution?

Ever heard of Spontaneous Fission
This is exactly the same process that happens in a nuclear reactor except that it is not self sustaining. pretty much all heavy (more than mass 100) naturally occuring isotopes will spontaneously fission though there are vast differences in the rate at which they do so.Note that ALL fissions directly release a neutron as part of the process so a secondary substance is not required to "react" with an Alpha particle.Possibly Radon gas might be one of the most abundent sources of fission neutrons in underground areas. It is well known to be extremely mobile.

No the neutron isn't mobile. It travels in a straight line for an inch or so before it loses its energy.
The point is that the N14 atom will need to be in extremely close proximity to the the Radon or other heavy isotope nucleous when it fissions. You are quite right here. It is also quite irrelevent since spontaneous fission directly produces a free, high energy Neutron. It doesn't need to first make an Alpha.

Alpha particles are not involved in the process of fission.
Berylium is rather a special case. It is often used in nuclear reactors as a reflecting shield material as it helps a smaller mass of uranium to achieve criticality by sending neutrons back into the uranium.One note also on the term "Neutron Flux"
What this actually means is the neutron density at a given point. When the flux reaches a certain level then a chain reaction will begin.
In underground situations, the flux could be as low as one neutron every minute or so. In a small working reactor at 10MWatts (with highly enriched fuel), it is something like 2E14 neutrons/second.
It isn't really appropriate to talk about flux in the Earth

Something like that. It all depends on the density of the surrounding material. In dense rock it is likely to hit something within an inch or two. In a reactor we only need a couple of centimeters or less of shielding to stop all the neutrons. They aren't good at penetrating stuff but they do one hell of a lot of damage to the stuff they hit.I don't have a ready source of information to reference. I'm just basing my information on what I have picked up over the last 6 years working at a research reactor. I will see if I can find something.

I managed to dig up a load of complex calculations about the mean free path of a thermal neutron through various materials. Not many real examples though.
The defining factor is the density of the surrounding material and the probability of interactions between Neutron and Target. This is dependent on the Barns radius This is about the best explanation that I managed to find

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By comparing the photon and neutron results we can see that of the two the neutron cross sections are much higher, so that fewer neutrons are transmitted through the 30 cm thickness of water, e.g., with a mean free path of only 2.1 cm there is only a very small probability that any 1 MeV neutrons will be transmitted through the water.

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My earlier description of spontaneous fission as a potential cause for N15 to capture a neutron was a little simplistic.
What actually happens is that a fast neutron is emitted by fission but this has way too much energy to be captured so it is likely to collide with other neclei in the vacinity and cause them to also fission. This secondary fission will release much lower energy (thermal) Neutrons which are able to be captured by the N14 (or any other nucleus) Often the resultant nucleus will be unstable or meta-stable and will quickly decay, releasing beta or alpha particles along with Gammas. Some of these may cause further reactions, possibly resulting in a thermal neutron (in the case of the Alpha colliding with a nucleus such as Beryllium).
Each initial fission will most likely result in a cascade of minor nuclear reactions and could result in the production of many thermal neutrons which could potentially be the source of C14.
The radius of such a cascade is probably still only in the region of a few inches from the initial fission.

Not to be too picky but N2 is a gas. N14 is an atom and as such can be bonded to other atoms as part of a molecule.

No I am not.
Even non-radioactive nuclei have a small chance of decaying via spontaneous fission.
Regular decay Alpha, beta and Gamma do not directly produce a neutron. The reason that Uranium is able to "go critical" ironically has absolutely nothing to do with its radioactivity. It is just that Uranium has a very high probability of spontaineously fissioning so when enough Uranium atoms are placed close together the neutrons set off a sustainable chain reaction (criticality)When Uranium fissions, it does not follow the normal decay route buy emitting alpha or beta particles. It splits right down the middle, leaving elements around mass 100-150. See this Nuclear Fission entry at wikipedia. it is pretty accurate.
Normally the fission is caused by the nucleus combining with a thermal neutron such as the case with U235 in a reactor but the chain reaction is initiated by spontaneous fission.
from the same wiki article

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All fissionable and fissile isotopes undergo a small amount of spontaneous fission which releases a few free neutrons into any sample of nuclear fuel. The neutrons typically escape rapidly from the fuel and become a free neutron, with a half-life of about 15 minutes before they decay to protons and beta rays. The neutrons usually impact and are absorbed by other nuclei in the vicinity before this happens. However, some neutrons will impact fuel nuclei and induce further fissions, releasing yet more neutrons. If enough nuclear fuel is assembled into one place, or if the escaping neutrons are sufficiently contained, then these freshly generated neutrons outnumber the neutrons that escape from the assembly, and a sustained nuclear chain reaction will take place.

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A typical fission event could be something like
U235 + N ---> U236 (unstable) ---> Kr92 + Ba141 + 3N But it is by no means certain what the outcome will be.Hope this helps to clear up any misunderstandings

I wondered where you hung out I actually run the ICPMS program at the reactor, as plasma mass spectrometry is my field. Can't help picking up stuff about the nuclear side of things though, especially when half the time I end up writing the software that they use to determine safe shipping levels.

It's a bit hard to determine whether it does or not.
U238 is pretty stable. It has a half life of 4.47 Billion years (4.47E9) and a Fission half life of 8E15 years (That's where the ratio comes from)lets do the math and see.
First we need to know a ballpark figure for Uranium concentration in soil. Googling around, I came up up with this site that claims a maximum of 11ppm in South Dakota. I really don't know if this is typical or not but let's take 10ppm as the norm just for the hell of it.That means that for every kilogram of soil, there are 10 miligrams of Uranium.
1 mol of Uranium (238g) = 6.02E23 atoms (Avagadros number)Therefore 10 miligrams of soil would contain 2.52E19 atoms of Uranium (sounds a lot doesn't it?)It would take 1 half life of 8E15 years to cut this value in half (if all the decay was via fission)
So to calculate the number of atoms lost due to fission alone per year, we would simply divide half the present number of atoms by the half life.
This gives us a value of 3151 fissions per year for 1Kg of soil
That is 8.6 fissions per day.
(I have assumed a linear rather than exponential decay for simplicity here. An exponential decay would mean a slightly higher rate NOW and a much lower rate LATER)Trying to estimate how many of those fissions would result in a Neutron colliding with a N14 atom is a bit beyond me but it is an interesting point that the thermal cross section of N14 is considerably higher than average at 1.8 Barns units. Most isotopes are less than 1.So in answer to your question, yes I think it could potentially be a significant contributor to the C14 levels in soil.One other thing too. C12 can capture a Neutron to form C13 (another stable isotope) then this can capture a second Neutron to become C14 so we have another possible route other than via N15. The pathway is very minimal though.

Hmmmm. Interesting. I hadn't thought of that.Check This site out
Apparently C14 is listed as a known COPC (Contaminent Of Potential Concern) in nuclear fuel rods as it is one of the direct fission products of U235You will find table 2 (the list of COPCs) about a third of the way down the page.I managed to find quite a number of sites that confirm this too.Very interesting. I wonder if there are any more ways to make C14?

I don't know a lot about this alpha particle path. Do you have any good information links on it?
Anyway, I'm not trying to say that spontaneous fission is the only possible route for C14 formation or even the major possible route. I just wanted to point out that it is one of several possible routes that should not be ignored.I just found This while i was googling around.
It is an online calculator that works out the number of neutrons produced from Uranium under various conditions. I'm not even sure i am using it right though. It doesn't seem to agree with the rate that I worked out earlier.
Ah well. maybe i got it wrong

As would lead, gold, Mercury, Bismuth Thulium and any other atom above mass 200. The thing is that spontaneous fission is incredibly rare in most elements and only becomes significant at masses above 230.
I don't expect Radon to be a major Neutron contributor.
In my earlier examples I showed a kilogram of soil (10mg of U238) producing a few neutrons per day just from U238. At a pure guesstimate I would expect a similar mass of Radon to produce one or two per week.EPA guideline list the action level for Radon in the home at 4 pico-Curies per liter of air.
This translates to 0.148 alpha particle emmisions per second per liter of air
Spontaneous fission is (again guesstimated) a million or so times less frequent. Maybe one or two neutrons per week for your entire basement. Here is what the EPA has to say about Alpha particles

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Alpha particles don't get very far in the environment. Once emitted, they travel relatively slowly (at approximately one-twentieth the speed of light) due to their electric charge and large mass. They lose energy rapidly in air, usually expending it within a few centimeters. Because alpha particles are not radioactive, once they have lost their energy, they pick up free electrons and become helium.

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Alpha particles also cannot penetrate most matter they encounter. Even a piece of paper, or the dead outer layers of human skin is sufficient to stop alpha particles.

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Remember that in order to produce a neutron, the alpha particle has to collide with, and fuse to, a very light isotope such as beryllium or Boron. (Note this is NOT cold fusion. It is actually very very hot)
It also has to do it in a very short distance before it captures a couple of electrons and becomes Helium.
In air, the probability of this kind of reaction makes spontaneous fission look positively common.
The only real danger of Radon is getting it inside your body where the Alpha particles can do some damage.The EPA have never said they do not believe spontaneous fission and/or alpha fusion is happening. They just don't consider it worth mentioning due to its infrequency in your basement.
It IS happening, just not at rates which pose a significant health risk.It's happening down in the ground too. It doesn't matter what the rate is. If a kilogram of soil only manages to produce 1 or 2 C14 atoms per year (by whatever method) then this is still enough to give a continuous background level when you measure it by mass spec.
Modern mass spectrometers can easily detect one atom in a 10E12 atoms (1part per trillion)

Does this actually happen?
I haven't been able to find any kind of information on Alpha particles fusing with Oxygen, Nitrogen or Carbon.
All I can find are references to Beryllium, Boron and possibly Lithium along with the reaction pathways.I'm not saying you are wrong. I simply don't know and want to find out.

What I meant was does it liberate a neutron, not does it react in some way.
All I can find on Alpha-Nitrogen interactions is the research performed by Rutherford in which it says..

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Rutherford was able to demonstrate, in 1919, that alpha particle could knock protons out of nitrogen nuclei and merge with what was left behind. The most common isotope of nitrogen is nitrogen-14, which has a nucleus made up of 7 protons and 7 neutrons. Subtract a proton and add the 2 protons and 2 neutrons of the alpha particle and you end with a nucleus possessing 8 protons and 9 neutrons. This is oxygen-17. The alpha particle can be considered as helium-4 and the proton as hydrogen-1.

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It follows then that Rutherford had successfully carried through the first man-made nuclear reaction:

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nitrogen-14 + helium-4 --> oxygen-17 + hydrogen-1

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This is a true example of transmutation, the conversion of one element to another. In a way, it was the climax of the old alchemical goals but it involved elements and techniques of which the alchemists had never dreamed.

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In this example, a proton was produced rather than a neutron. The proton quickly grabbed a free electron to become Hydrogen.
I suspect that "light" probably refers to "lighter than carbon" for this reaction to produce a free neutron. I haven't been able to find the information to substantiate this yet though.

Thanks Sidelined.I have found a whole bunch of references to the triple alpha process (followed by a single Alpha capture)
As you say, they only talk about stellar temperatures and pressures.
It does appear that the stoichiometry of the reaction would not allow for the production of a free neutron though.
Again I would strongly suspect that this would also be the case at normal Earthlike conditions, but I can't be absolutely certain.What we do know is that Lithium, Berylium and Boron will fuse with a free Alpha particle (Helium4 nucleus) and release one of more free neutrons.
We also know that Nitrogen will fuse with an Alpha particle to make Oxygen and a proton (Hydrogen)
I have found hints that Oxygen can also be fused to form Neon without any other particle produced but that reaction is incredibly rare even at stellar temperatures and pressure so I doubt that it happens on Earth at any kind of measurable rate.Carbon would appear to make stable Oxygen when hit by an Alpha
from the site you linked

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C12 + He4 ’ O16 +

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I think at this point I feel confident enough to tentatively state that Radon in your basement does not cause the production of any free neutrons by Alpha decay (unless you have a basement full of airborn Beryllium dust in which case neutrons are the least of your worries)
The only possible route is via spontaneous fission and even that is incredibly rare.I wouldn't start worrying about neutron radiation at home if I were you.