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Before I go to my question, let me refresh the basic principles of operation of a LASER (Light Amplification by Stimulated Emission of Radiation): an active medium is brought in an excited state and, when a trigger happens, all its atoms go back to a lower energetic state releasing photons with the same frequency, phase and direction of propagation of the trigger.

Well, during one of my nights at the Korova Milk Bar, I happened to discover the principle of what I have called NASER, or Nuclear Amplification by Stimulated Emission of Radiation.

In short, a radioactive atom is an atom in an high energy state, which randomly decays to a lower energy state by emitting radiation, alpha/beta/gamma rays. In the right conditions, which I have discovered, this is not left to chance but can be triggered in the same way as in a laser.

Basically, when I put a bunch of radioactive material in the device and pull a trigger, it will cause a coherent decay, followed by the emission of coherent radiation beam. In the MK1 device the type of decay cannot be tuned, while in the MK2 device it is possible to pick between decay type. For example, a sample of Uranium 238 would allow up to 14 shots through its entire decay chain until it turns into Lead. The device adds no energy to the decay, it just makes it happen.

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Now, I imagine that the sharpest among you are happy: "finally we can solve the problem of nuclear waste! Free and clean energy for everybody!". Well, the problem is that my research (and my visits to the Korova Milk Bar) are funded by General Sivispacemparabellum, who is, to put it mildly, a tad allergic to pacific applications, and wants something which can be used as a weapon.

And this is my question to you: can such a device be used as a weapon? And if so, how? Alpha and beta rays are easily stopped, while gamma rays take days to kill someone. I am at a loss and don't want to become the general's umbrella holder.

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    $\begingroup$ A good thing you didn't use neutrons for simulated emission of other neutrons. I reckon there still are some Japanese people that still resent the past experience involving a Neutron Amplification by Stimulated Emission of Radiation. $\endgroup$ Nov 18, 2021 at 17:34
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    $\begingroup$ Part of the question says only alpha and beta particles come out and a later part of the question mentions gamma radiation, which is it? If you've got gammas coming out, you either have a gamma ray laser or can get a neutron beam by photodisintegration of atoms for long range space weaponry. $\endgroup$ Nov 18, 2021 at 20:13
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    $\begingroup$ @GrumpyYoungMan, my understanding was that gamma emission happens together with alpha or beta decay. Any, I made that part coherent with the rest of the question. $\endgroup$
    – L.Dutch
    Nov 19, 2021 at 3:45
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    $\begingroup$ Not a full answer, but "loads of free, cheap energy" has plenty of military applications of its own on large vehicles and installations like ships, hidden bases, spaceships or whatever you military has that needs to be powered. $\endgroup$
    – Erik
    Nov 19, 2021 at 7:54
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    $\begingroup$ @IanKemp Not quite. A nuclear pumped laser still fires a photon beam, it just uses radiation to excite the light emitting medium. This question seems to be about weaponizing the radiation directly. $\endgroup$
    – Nosajimiki
    Nov 19, 2021 at 16:18

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You can weaponize it, and it will be devastating

The fact that Alpha and Beta radiation are do not pass through much matter before being stopped does not mean they can not transfer vast amounts of energy. When we say they are stopped, what we mean is that they collide with something and have some sort of reaction (as opposed to passing though without hitting anything like gamma radiation does).

The fact that Alpha particles are normally harmless mostly boils down to the small number of particles you normally experience at a time, but particle per particle, they transfer a massive amount of energy. Alpha radiation is made of Protons and Neutrons accelerated to about 6% of the speed of light, and when Uranium 238 decomposes to Thorium 234, it looses about 0.4% of its mass.

So, to figure out how devastating this is, let's say you have a 1kg Uranium fuel source. You will be accelerating 4.2 g of matter to about 18,000,000 m/s. Resulting in a 680.4 GJ impact which is about 15 times as powerful as the most powerful conventional bomb ever used in combat.

A beta radiation NASER would be similarly powerful. Beta radiation is made up of electrons moving at about 90% of the speed of light; so, much less mass, but much more velocity yielding similar amounts of energy.

The biggest advantage of this system though is that you are not relying on a neutron chain reaction to initiate fission, this means you have no minimum critical mass to consider; so, if you wanted to make a NASER small enough to take out a tank, and only a tank, you could reduce your fuel down to just a few milligrams of uranium, and still fire a weapon that is a comparable to firing a laser in the megawatt range. This also means a very small "ammo clip" is needed to hold thousands of rounds of ammo for this weapon.

The hard part as Nathaniel pointed out in comments will be getting that radiation to travel over a great distance without dissipating into and reacting with the atmosphere. Luckily, this is already a problem we've solved in the form of electrolasers. An electrolaser is a kind of electron particle weapon that exists in real life that involves first firing a powerful but brief laser pulse creating a small tube shaped vacuum surrounded by plasma in the air. This plasma tube acts as a sort of temporary wire that you can funnel a stream of electrons down extending a weapons range way beyond the few cm you can normally get electrons to fly through normal air. So your beam weapon will actually begin it's attack with a LASER to create a clear path to the target, and then project the NASER through it.

The other hard part is that you can't just push out a lot of electrons or protons from a fuel source, and expect what you leave behind to be stable, so in all likelihood, your weapon is actually going to emit a pulse of all 3 kinds of radiation if you want to have a not critical Thorium ingot left behind.

Another valuable thing this can be used for is creating nuclear rockets. (Sometimes the Kzinti Lesson works in reverse.) The problem with all of our current designs of nuclear rockets is the minimum critical mass issue. Because we can only make a nuke so small it is very hard to create a reaction that can push a efficiently without also vaporizing it. This invention means you can make arbitrarily scaled, and directional amounts of thrust which could result in a new generation of hypersonic aircraft and missiles.

General Sivispacemparabellum would very much be interested in funding your research, but depending on how he chooses to use it, you may come to wish he hadn't.

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    $\begingroup$ Another interesting aspect related to this answer is that emitting all those particles as a beam necessarily generates a recoil force, thanks to Newton's Third Law. So the NASER is also potentially a very powerful rocket engine but without any of the difficulties with respect to fuel, heat, and so forth. The military applications to aircraft, missiles, etc. would plentiful. $\endgroup$ Nov 18, 2021 at 23:23
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    $\begingroup$ "ability to direct that energy into a unidirectional beam" +1. Weaponized, yes. Personal firearms, no. $\endgroup$
    – Mazura
    Nov 19, 2021 at 1:12
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    $\begingroup$ @Seraphim It would but alpha/beta radiation (a.k.a. helium nuclei and electrons) are short ranged and taking risks with radiation, within limits, would probably be acceptable for military applications. $\endgroup$ Nov 19, 2021 at 1:27
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    $\begingroup$ Your particles leaving the gun at such a significant fraction of the speed of light will interact with the air right in front of your gun. That could become an issue for the shooter. what-if.xkcd.com/1 $\endgroup$
    – vsz
    Nov 19, 2021 at 8:32
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    $\begingroup$ The problem is that alpha particles can only travel a few centimetres in air and beta particles only a few metres. So the energy in that unidirectional beam is going to be very efficiently transferred to the air just in front of it, making it overall not very much different from a bomb at all. It would be a pretty devastating space weapon, though. $\endgroup$
    – N. Virgo
    Nov 19, 2021 at 8:32
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It's called Induced Gamma Emission

This idea has been around for some time, and there was a successful but irreproducible result. Obviously the notion of storing vast amounts of nuclear energy in a small space and tapping it on demand, perhaps even in a non-radioactive environment ... well, that is very appealing. But it might also be used as the initiator of a nuke, or an explosive in its own right. So whether it works or not ... we're not going to hear about it, not unless someone starts killing large numbers of people with it, and probably not even then.

You may also be interested in gamma ray lasers.

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    $\begingroup$ Was it really "successful" though? The report from the LLNL even states that "[the tests were] statistically marginal and inconsistent. None of the reported positive triggering results were confirmed by independent groups". IMO, especially in science, something that isn't experimentally verifiable isn't successful. $\endgroup$
    – Dragongeek
    Nov 21, 2021 at 13:25
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    $\begingroup$ I think my phrase "successful but irreproducible" is sufficient to reflect the spirit of your response. :) $\endgroup$ Nov 22, 2021 at 1:06
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As others have said this hypothetical weapon would be devastating, you effectively have proposed a mechanism to convert the energy of a nuclear fuel that would normally take hundreds or perhaps thousands of years to radiate its energy into an almost-instant death beam.

It is essential however for the working of a laser (or similar device) that the particles involved have spin 1 – these are called bosons. They tend to "bunch up", they like being in the same mode at the same time. This is what allows a laser to work – all the photons are bunched into a single mode beam.

On the other hand fermions (spin 1/2 particles) are the opposite, you can't place two identical fermions in the same mode at the same time.

So, at least with modern physics, the Beta-particle version of your device looks impossible. The gamma/alpha versions I think are fine.

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Well if enough of the atoms decay rapidly enough you will essentially create the same effect as a fission bomb.

Assuming the device doesn't explode, any radioactive decay will still produce a lot of decay heat. Your first challenge is going to be keeping the device from melting.

The most straightforward way to keep your device from melting would be if all of the thermal radiation created from the nuclear decay left the device in the form of a beam. In that case your weapon simply heats the target until they burn, vaporize, etc.

Overall that would be strikingly similar to getting hit with a regular LASER.

The main advantage over a regular LASER is of course that you have a portable nuclear power supply for your device. Typically regular laser systems are constrained by needing large power sources.

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It's a warhead, not a delivery mechanism.

Alpha and beta rays are easily stopped […]

Why is that a problem? TNT has basically zero range. So do HBX, RDX, and any other number of three-letter acronyms that will definitely look very suspicious showing up right next to each other here. Bullets are easily stopped too. But that doesn't stop any of these things from being used to break stuff and hurt people.

As @Nosajimiki pointed out, what you've done is to basically create a nuclear bomb design that has no lower limit on size. Is its potential as a weapon really diminished by the fact that it doesn't also produce a flashy sci-fi beam?

All existing weapons will be enhanced to terrifying effectiveness. A handgun will be able to take out an entire building. A consumer quadcopter will be able to vaporize multiple city blocks. To take out every tank in an invading batallion, you just need to bury a fistful of mines each the size of a penny. To sink a whole naval carrier group, you just need to scatter those mines in the general region where they're sailing.

Modern militaries have invested billions of dollars into stealth, sensor, and active defence technology. Overnight, they'll all be obsolete. It will no longer matter how many rounds per minute a point defence cannon fires when the projectiles it has to shoot down are so small that they'll always slip through, and so small that a single $100 drone can carry thousands. There will no longer be any use for expensive fighter jets designed to have the radar signature of a coke can, because they no longer have to carry thousands of pounds of ordnance with them, which means that it will be easier to just build one-shot missiles with terminal stages that are the size of a coke can.

The U.S. MOAB squeezes a 46GJ explosion into an 18,700lb package so big that it can only be dropped by cargo aircraft; Your invention can pack all that destructive force into a volume less than a third of a teaspon. No radar, sonar, or interceptor missile will be able to do anything when hundreds of incoming projectiles are simply too small to see until they're too close to stop.

(Perhaps the General's enemies would figure out how to shoot down incoming micro-nukes by airbursting their own micro-nukes to saturate an entire volume of air with enough energy to fry them, like a stream of tiny AIR-2s.)

The short range isn't a problem, because all each warhead has to do is the job of a shaped charge at ranges less than a few meters. You're likely not ever going to get an effective range more than a couple dozen meters out of this, no matter what anybody says. Even in a vacuum, alpha particles are all positive and beta particles are all negative, so your "beam" is going to start trying to spread itself out into a cone as soon as it's emitted if it's dense enough to do any real damage.

But that won't make the General any less happy, because the problem of how to get a short-ranged but large energy release close enough to a target to apply an effect is one that has existing solutions. And those warheads are going to be nearly impossible to stop when they can be made a hundred times more powerful in a package a thousand times smaller.

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The key feature of LASER, same for MASER, is within the particle beam that is amplified. In both cases it is a photon, theoretical particle of raw energy with zero static mass.

In other words, photons can show up from "nowhere" and completely disappear "elsewhere".

In both LASER and MASER, the atoms or molecules, more precisely their electron structures, are excited and then trapped in metastable state. This means, that there is no "allowed" way how to deexcite further to the ground state.

Actually, it means that the metastable state can last few microseconds compared to nanoseconds for "orodinarilly excited" stated.

When appropriate photon "flies by" it stimulates the media and they deexcite immediately.

Do not forget, that for excitation the energy is consumed (for example by absorbing a photon, phonon, etc.) and deexcitation directly leads to photon emission.

The key message form this part is: Photons does not consume matter. Laser works and does not need to renew the medium, it consumes energy and it produce energy.

Your NASER as proposed cannot work like that, except for GASER - Gamma-ray amplification... for just simple reason, all other rays do have static mass and cannot appear and disappear.

In other words, the medium will be consumed throughout the working time.

But let us give some unobtainium and handwavism not to spoil the fun and have such a gun!

From the above, it is clear the weapon will need to use cartriges to renew the ABASER (alpha/beta amplification) unit.

There is yet another problem to solve. Uranium is quite innocent pal with long decay. But throughout the chain ending in stable lead there are some long-lasting and nasty ones and some decay within minutes.

So it will be handy to finetune the device to stimulate all the decays in the one burst. Then throw the lead cartrige out.

The other problem you have to face is the medium where you are to fire to...

Alpha particles are, actually, nuclei of stable Helium. That is their core feature and that is why they are so dangerous. They carry a lot of energy and their ionisation capacity is +2. In the ambient air the free path, the distance a particle has highest probability to fly without hitting any other is 68 nm. THis is the reason alpha-rays are so short distance. Even though they are bloody fast (the efective hit cross-section decreases with speed) they are trying to fly through a dense forrest.

Beta particles are either bloody fast electrons or antielectrons, that does not possess that high ionisation capacity but they fly through the air slightly easier.

Vacuum is your friend here, so let's go to stars with your wapons. Such a technology calls for spacecraft deployment!

In the interplanetary vacuum the beams can be focused and range longer.

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