Anti-matter weapons

ahrkron

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I think this is crackpot material.
 

Astronuc

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IMO, this is rather impractical since anti-matter production rates are extremely low (IIRC < pico-grams/yr) so it would take roughly >1000 years to get on the order of nano-grams - and that would have to be anti-hydrogen of some form.

IIRC, there is not satisfactory storage system for any quantity of molecular antihydrogen. This would require bringing anti-protons and positrons to rest in a magnetic container - in molecular form. :rolleyes:
 
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ahrkron said:
I think this is crackpot material.
Iam puzzled as to why anyone would present a paper which is obviously outdated?
 
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Astronuc said:
IMO, this is rather impractical since anti-matter production rates are extremely low (IIRC < pico-grams/yr) so it would take roughly >1000 years to get on the order of nano-grams - and that would have to be anti-hydrogen of some form.

IIRC, there is not satisfactory storage system for any quantity of molecular antihydrogen. This would require bringing anti-protons and positrons to rest in a magnetic container - in molecular form. :rolleyes:
If we can store plasma in an electromagnetic field, what about anti-plasma?

Edit: And if we really had to make loads of anti-matter for military reasons, I think it would be more a matter of cost than of time. I'll be honest, I don't have a clue how we make anti-matter, but presumably we can build a device that does it. So, it should make sense that we could make more of those devices. After that, it's just a factor of having enough available energy. As I said, it all comes down to money, and anti-matter isn't needed on an economic or military scale yet, so one shouldn't be surprised that we aren't presently making much. It's a little like saying the oil production rates of the 1600s would hold steady throughout the rest of the millenia.
 
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Astronuc

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Anit-matter is produced in accelerators, in which protons collide with other protons at combined kinetic energies > 1.88 GeV, while electrons are collided with combined kinetic energies > 1.022 MeV.

The two leading facilities for antiproton production and storage are the European Laboratory for Particle Physics (formerly CERN, the Center for European Nuclear Research) in Geneva, and the Fermi National Accelerator Laboratory (FNAL) in the United States. At the CERN facility, protons are accelerated by a linear accelerator to 50 MeV (8x10-12 J), injected into a booster ring and accelerated to 800 MeV, and then sent to a proton synchrotron, where they are further accelerated to 26 GeV. The high-energy protons are then focused into a 2-mm beam and directed into a 3-mm diameter, 11-cm long copper wire target. The relativistic protons collide with the target nuclei, producing a spray of gammas, pions, kaons, and baryons, including antiprotons. On leaving the target, the antiprotons have a peak momentum of 3.5 GeV/c, corresponding to a peak energy of roughly 3 GeV. A short focal length, pulsed magnetic horn is used to capture antiprotons that have momenta within 1.5% of their peak value, at angles up to 50 mrad from the target centerline. The captured antiprotons are sent to a storage ring in bursts of about 107 antiprotons every few seconds, and around 1011 antiprotons can be accumulated before space charge effects scatter the circulating beam. The antiprotons are sent back to the proton synchrotron, which decelerates them to an energy of 200 MeV, and then to the low energy antiproton ring, where the circulating beam is further decelerated, stochastically cooled, and stored. Similar techniques are used to create antiprotons at FNAL.
from http://gltrs.grc.nasa.gov/reports/2001/CR-2001-211116.pdf [Broken] pdf file (click on to open or save target as)

Scientists in 1995 succeeded in producing anti-atoms of hydrogen, and also antideuteron nuclei, made out of an antiproton and an antineutron, but no anti-atom more complex than antideuterium has been created yet. In principle, sufficiently large quantities of antimatter could produce anti-nuclei of other elements, which would have exactly the same properties as their positive-matter counterparts. However, such a "periodic table of anti-elements" is thought to be, at best, highly unlikely, as the quantities of antimatter required would be, quite literally, astronomical.

Antiparticles are created elsewhere in the universe where there are high-energy particle collisions, such as in the center of our galaxy, but none have been detected that are residual from the Big Bang, as most normal matter is [1]. The unequal distribution between matter and antimatter in the universe has long been a mystery. The solution likely lies in the violation of CP-symmetry by the laws of nature, see baryogenesis.

Positrons and antiprotons can individually be stored in a device called a Penning trap, which uses a combination of magnetic field and electric fields to hold charged particles in a vacuum. Two international collaborations (ATRAP and ATHENA) used these devices to store thousands of slowly moving antihydrogen atoms in 2002. It is the goal of these collaborations to probe the energy level structure of antihydrogen to compare it with that of hydrogen as a test of the CPT theorem. One way to do this is to confine the anti-atoms in an inhomogenous magnetic field (one cannot use electric fields since the anti-atom is neutral) and interrogate them with lasers. If the anti-atoms have too much kinetic energy they will be able to escape the magnetic trap, and it is therefore essential that the anti-atoms are produced with as little energy as possible. This is the key difference between the antihydrogen that ATRAP and ATHENA produced, which was made at very low temperatures, and the antihydrogen produced in 1995 which was moving at a speed close to the speed of light.

Antimatter/matter reactions have practical applications in medical imaging, see Positron emission tomography (PET). In some kinds of beta decay, a nuclide loses surplus positive charge by emitting a positron (in the same event, a proton becomes a neutron, and neutrinos are also given off). Nuclides with surplus positive charge are easily made in a cyclotron and are widely generated for medical use.
from Antimatter production - Wikipedia. See also Antimatter as fuel on same webpage.
 
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Rade

I have a question. From the link cited above: http://gltrs.grc.nasa.gov/reports/2001/CR-2001-211116.pdf [Broken]
I read that at CERN, 26GeV "protons" (with quark structure uud) are made to collide with a copper wire (having very complex quark structure). The collision thus produces "antiprotons" (with quark structure u^u^d^, where ^ = symbol for antiquark)

My question is, from where does the (u^u^d^) come from that is observed in this collision, the "proton", the "copper", both, or neither ? That is, how can two "matter" entities form "antimatter" ? Thanks for any help you can provide.
 
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Rade said:
I have a question. From the link cited above: http://gltrs.grc.nasa.gov/reports/2001/CR-2001-211116.pdf [Broken]
I read that at CERN, 26GeV "protons" (with quark structure uud) are made to collide with a copper wire (having very complex quark structure). The collision thus produces "antiprotons" (with quark structure u^u^d^, where ^ = symbol for antiquark)

My question is, from where does the (u^u^d^) come from that is observed in this collision, the "proton", the "copper", both, or neither ? That is, how can two "matter" entities form "antimatter" ? Thanks for any help you can provide.
Quote:The high-energy protons are then focused into a 2-mm beam and directed into a 3-mm diameter, 11-cm long copper wire target. The relativistic protons collide with the target nuclei, producing a spray of
gammas, pions, kaons, and baryons, including antiprotons.

They are a 'By-Product' of certain events, at certain times.
 
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Rade

Thank you Spin Network -- clearly the antimatter observed is a "by-product" of "certain events"-- but this does not answer my question.

I wish to know the "dynamics" of the "certain event(s)" -- i.e., what model of nuclear physics explains how the antimatter is formed ? -- it has to be one of these logical possibilities:(1) the antimatter observed derives from the proton projectile, (2) the antimatter derives from the copper target, (3) it derives from a quark combination of both projectile + target, (4) it derives from neither projectile nor target. Are we saying that QCD and the Standard Model cannot explain the "dynamics" ? My interest in this question derives from the possibility that the "antiproton" exists as a parton quark structure within the proton projectile.
 
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Why couldn't the antimatter just develop from a virtual particle interaction or a decay of a virtual particle in a high-energy environment? Once you start making real particles out of kaons and other peculiar beasts you can probably get the components for a whole host of anti-protons.

In order to answer that question specifically you would either have to look it up (and I don't have time at the moment) or simulate it yourself, which would require a vast amount of computer power.
 
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Rade said:
Thank you Spin Network -- clearly the antimatter observed is a "by-product" of "certain events"-- but this does not answer my question.

I wish to know the "dynamics" of the "certain event(s)" -- i.e., what model of nuclear physics explains how the antimatter is formed ? -- it has to be one of these logical possibilities:(1) the antimatter observed derives from the proton projectile, (2) the antimatter derives from the copper target, (3) it derives from a quark combination of both projectile + target, (4) it derives from neither projectile nor target. Are we saying that QCD and the Standard Model cannot explain the "dynamics" ? My interest in this question derives from the possibility that the "antiproton" exists as a parton quark structure within the proton projectile.
My limited knowledge is based on my own personal theory, it would not be useful to divulge what I cannot prove, yet.

Saying that, of the choices above I would contend that (3) is most likely.
 

Rade

Thank you danAlwyn & Spin Network. First, I do not think the antiproton can be formed by pions since they decay into muons not up-down quarks--we need up-down antiquarks to form antiproton. Likewise the kaon does not have a down quark (only up and strange)--hence neither can it form antiproton. But perhaps Lambda is a possibility if the antiproton comes from the zero-point vacuum.

One of my motivations for this question is the following paper which suggests that "antiprotons" are real structures already within nuclei (that is, not formed by reaction), just released from either the projectile or target or both ?--a radical point of view--see Antibaryons in Nuclei, Phy Rev C 71, 2005 cited below. I would like to suggest that the antiproton is a real entity within 1-H-1, the proton.

Physical Review C
Vol: 71, Issue: 3, March 04, 2005
pp. 035201 - 035232

Title: Antibaryons bound in nuclei
Authors: Mishustin, I. N.a; Satarov, L. M.a; Bürvenich, T. J.b; Stöcker, H.a; Greiner, W.a Affiliations: a. Frankfurt Insitute for Advanced Studies, J.W. Goethe Universität, D-60054 Frankfurt am Main, Germanyb. Institut für Theoretische Physik, J.W. Goethe Universität, D-60054 Frankfurt am Main, Germany

Abstract: We study the possibility of producing a new kind of nuclear system that in addition to ordinary nucleons contains a few antibaryons (B<over>-</over>=p<over>-</over>,Λ<over>-</over>, etc.). The properties of such systems are described within the relativistic mean-field model by employing G-parity transformed interactions for antibaryons. Calculations are first done for infinite systems and then for finite nuclei from 4He to 208Pb. It is demonstrated that the presence of a real antibaryon leads to a strong rearrangement of a target nucleus, resulting in a significant increase of its binding energy and local compression. Noticeable effects remain even after the antibaryon coupling constants are reduced by a factor of 3–4 compared to G-parity motivated values. We have performed detailed calculations of the antibaryon annihilation rates in the nuclear environment by applying a kinetic approach. It is shown that owing to significant reduction of the reaction Q values, the in-medium annihilation rates should be strongly suppressed, leading to relatively long-lived antibaryon-nucleus systems. Multinucleon annihilation channels are analyzed too. We have also estimated formation probabilities of bound B<over>-</over>+A systems in p<over>-</over>A reactions and have found that their observation will be feasible at the future GSI antiproton facility. Several observable signatures are proposed. The possibility of producing cold multi-quark-antiquark clusters is discussed.

Publisher: American Physical Society
Item Identifier: 10.1103/PhysRevC.71.035201
 
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I haven't had a chance to read the paper yet, but it may not a huge bearing on our current problem, there theory seems to involve the anti-baryon being held inside the nucleus. A real proton doesn't seem to be able to "hold" a real anti-baryon in the same way, because that would make the single proton into an antiproton, and hence make it unstable. The oldest production of antiprotons currently known is:

p + p -> p + p + p + antiproton

This does not depend on the existence of a nuclei for stabilization purposes. All you have to do it create two up quarks, two anti-up, one down and one anti-down. I don't know what the cross-section is off hand, but pp collision generated antiprotons may be a large part of the LHC, so they should know.

It's certainly easier than generating that blasted Higgs.

Edited to actually address the question.
 
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Rade

A real proton doesn't seem to be able to "hold" a real anti-baryon in the same way, because that would make the single proton into an antiproton, and hence make it unstable.

Of course, what do we mean by "proton" ? It is now well known that the proton has much more internal structure than three valence quarks (uud). Also are the mesons in the proton sea, and the strange quark recently found.

I now study a model of the atomic nucleus by the late nuclear physicist R. Brightsen that views the proton as being the outcome of a quantum superposition of nucleon clusters. One form is to combine a matter [PNP] cluster with an antimatter [N^P^] cluster, where ^ = antimatter. The quantum outcome is a real [P] superposed state bound to an imaginary [NP][N^P^] state. In quark dynamics this resolves into a 6-antiquark bag (d^d^d^u^u^u^) rotating against a 9-quark matter bag (uuuuudddd)--that is, the concept of the nucleon and free quark disappears--the "bags" become the fundamental building blocks of nuclei. It is predicted that formation of colorless pions (d^u) or (u^d) allow for the matter and antimatter bags to bind (via interaction of positive mass and negative mass by gravity and antigravity), leaving (uud) = 1-H-1 (the proton) as the real quantum superposed (unbound) state that we observe. Thus the Brightsen model predicts potential for anti-baryon structure within 1-H-1, plus (important for low energy fusion reactions) that anti-deuteron structure is also part of the internal structure of 1-H-1.
 
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I don't think it's crackpot stuff at all.

In fact, I'm rather excited by the possibilities presented in the paper.

Let's get to work!
 

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