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Science

CERN Antimatter Experiment Produces First Beam of Antihydrogen 136

An anonymous reader writes "Matter and antimatter annihilate immediately when they meet, so aside from creating antihydrogen, one of the key challenges for physicists is to keep antiatoms away from ordinary matter. To do so, experiments take advantage of antihydrogen's magnetic properties (which are similar to hydrogen's) and use very strong non-uniform magnetic fields to trap antiatoms long enough to study them. However, the strong magnetic field gradients degrade the spectroscopic properties of the (anti)atoms. To allow for clean high-resolution spectroscopy, the ASACUSA collaboration developed an innovative set-up to transfer antihydrogen atoms to a region where they can be studied in flight, far from the strong magnetic field (scientific paper)."
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CERN Antimatter Experiment Produces First Beam of Antihydrogen

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  • by Anonymous Coward on Tuesday January 21, 2014 @04:33PM (#46029073)
    Sulphur Hexafluoride [youtube.com] already does this.
  • by Mashdar ( 876825 ) on Tuesday January 21, 2014 @06:14PM (#46029985)
    Do you mean does away with dark energy? Because dark matter is supposed to have positive mass, so I don't see how adding negative mass would remove the need for it?
  • Comment removed (Score:5, Informative)

    by account_deleted ( 4530225 ) on Tuesday January 21, 2014 @08:53PM (#46031433)
    Comment removed based on user account deletion
  • Re:ELIAAHM (Score:5, Informative)

    by joe_frisch ( 1366229 ) on Tuesday January 21, 2014 @08:58PM (#46031465)

    They turn into "energy", but it may not be very straightforward. Electrons and anti-electrons (positrons) usually annihilate to a pair of gamma rays - about as close to "pure" energy as you can get.

    Anti protons and protons annihilate in a more ugly fashion since each is a bag of quarks. You can get pions that decay into neutrinos and muons which then decay into positrons and neutrinos. The muon decay is fairly slow - ~2 microseconds, enough for them to travel almost a kilometer.

    In the end you get gamma rays, neutrinos (of various types), electrons and positrons. The combined energy (both their mass energy and their kinetic energy) of all the particles adds up to the original mass energy of the matter and antimatter, and any other energy put into the process.

    Because protons and anti-protons are complex, it is very difficult to make anti-protons - only something like 1/100,000 collisions generates one, the rest just make pions and other junk. Then once you have the anti-protons its difficult to slow them down enough and cool them to where they will combine with the positrons. Is a very impressive and complicated experiment.

    BTW- it is not a path to any reasonable energy storage, the efficiency of making anti-protons is much too low. I don't know of any even design concepts that would have usable efficiency.

I have hardly ever known a mathematician who was capable of reasoning. -- Plato

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