Antimatter devices

[The 321 Anomaly]

To the best of my understanding, nuclear fission occurs when the nuclei of fissionable isotopes (such as thorium-232, U-235, plutonium-239, etc.) are bombarded by neutrons and split into either krypton & barium or antimony and niobium. My colloquial/superficial research also indicates that as far as nuclear fusion, the process transpires when the nuclei of deuterium and tritium collide/coalesce, creating helium and giving off energy. My question is this - if an antimatter device were to become practical, what would be its general mechanism theoretically? It seems to me that positrons would probably be involved seeing as how they are one of the more well-known subatomic antimatter particles. Obviously the underlying science of atomic weapons is nuclear fission. Additionally, it is an established fact that the technical underpinnings of thermonuclear devices/hydrogen weapons are largely nuclear fusion, but presently no team of scientists has effectively innovated as far as antimatter devices.

[swansont]

Antimatter would annihilate, creating a bunch of gamma rays. That would be the general mechanism.

Fusion and fission devices are tapping in to a stored mass-energy of the nuclei involved. For antimatter, there is no stored energy. You have to create the antimatter and store it, and you put more energy in to this effort than you get out with a bomb. Which is one of the reasons there is little (visible) effort into such a device. 

1 minute ago, swansont said:

Antimatter would annihilate, creating a bunch of gamma rays. That would be the general mechanism.

Fusion and fission devices are tapping in to a stored mass-energy of the nuclei involved. For antimatter, there is no stored energy, because you have to make the antimatter first. You have also store it, and you put more energy in to this combined effort than you get out with a bomb. Which is one of the reasons there is little (visible) effort into such a device. Plus, the antimatter being very hard to store, making it quite dangerous.

 

[Moontanman]

7 minutes ago, swansont said:

Antimatter would annihilate, creating a bunch of gamma rays. That would be the general mechanism.

Fusion and fission devices are tapping in to a stored mass-energy of the nuclei involved. For antimatter, there is no stored energy. You have to create the antimatter and store it, and you put more energy in to this effort than you get out with a bomb. Which is one of the reasons there is little (visible) effort into such a device. 

 

Could antimatter be used to trigger a fusion reaction? If so this could result in fusion bombs that are much smaller or maybe even larger than current bombs and be considerable "cleaner" than current nuclear bombs? 

[swansont]

1 hour ago, Moontanman said:

Could antimatter be used to trigger a fusion reaction? If so this could result in fusion bombs that are much smaller or maybe even larger than current bombs and be considerable "cleaner" than current nuclear bombs? 

Possibly. But the Hiroshima bomb converted something a little less than a gram of mass into other forms of energy, so if the trigger were similar in size as this bomb you would need around a half a gram of antimatter for this. Antimatter is very expensive to make. 

"In 2006, Gerald Smith estimated $250 million could produce 10 milligrams of positrons" ($25 billion per gram)

https://en.wikipedia.org/wiki/Antimatter

And storage times for antimatter are currently fairly short

[Strange]

The Alpha project at CERN regularly makes "large" amounts of antimatter (more than anyone else, anyway). Their latest results are based on measurements of less than 200 atoms.

[swansont]

1 minute ago, Strange said:

The Alpha project at CERN regularly makes "large" amounts of antimatter (more than anyone else, anyway). Their latest results are based on measurements of less than 200 atoms.

At 6.02 x 10^23 atoms per gram, for hydrogen

[Moontanman]

2 hours ago, swansont said:

Possibly. But the Hiroshima bomb converted something a little less than a gram of mass into other forms of energy, so if the trigger were similar in size as this bomb you would need around a half a gram of antimatter for this. Antimatter is very expensive to make. 

"In 2006, Gerald Smith estimated $250 million could produce 10 milligrams of positrons" ($25 billion per gram)

https://en.wikipedia.org/wiki/Antimatter

And storage times for antimatter are currently fairly short

To be honest, like almost any other technology, I would expect it eventually to become much cheaper. I wonder how much money it took to separate out the first plutonium... 

[swansont]

4 minutes ago, Moontanman said:

To be honest, like almost any other technology, I would expect it eventually to become much cheaper. I wonder how much money it took to separate out the first plutonium... 

$23 billion in 2007 dollars for the whole Manhattan project. So something less than that for the first plutonium separation.

https://www.ctbto.org/nuclear-testing/history-of-nuclear-testing/manhattan-project/

[StringJunky]

Quote

Positron-emission tomography (PET)[1] is a nuclear medicine functional imaging technique that is used to observe metabolic processes in the body as an aid to the diagnosis of disease. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide (tracer), which is introduced into the body on a biologically active molecule. Three-dimensional images of tracer concentration within the body are then constructed by computer analysis. In modern PET-CT scanners, three-dimensional imaging is often accomplished with the aid of a CT X-ray scan performed on the patient during the same session, in the same machine. https://en.wikipedia.org/wiki/Positron_emission_tomography

Is this not a utilisation of antimatter?

[The 321 Anomaly]

Your answer to my initial question was much appreciated, swansont. It makes sense that antimatter would annihilate itself, especially since that was possibly what happened early on in our universe's history (with the obliteration of the majority of the Cosmos' atoms that existed prior to this primordial annihilation). I wasn't aware that matter-antimatter annihilation gave rise to the occurrence of gamma rays.

Edited March 4, 2018 by The 321 Anomaly