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Origin of Cosmic Rays Confirmed

cats-paw writes in with news of research that seems to confirm and support current theories of how cosmic rays are created. The prevailing thinking has been that cosmic rays are generated in the regions where supernovas' shock waves interact with the interstellar medium. The new research used the variability in X-ray emissions from a supernova remnant to estimate the strength of the magnetic fields present in that environment. The results lend support to the possibility of protons and nucleii being accelerated in supernova remnants to energies of 1 PeV (10^15 eV) and beyond. Here is the abstract from Nature.

15 of 155 comments (clear)

  1. d'oh by User+956 · · Score: 4, Funny

    research that seems to confirm and support current theories of how cosmic rays are created.

    Oh, great, now that everyone knows how to make them, the Fantastic Four are going to be up to their eyeballs in supervillainry.

    --
    The theory of relativity doesn't work right in Arkansas.
  2. [OT] Nitpicking summary by noidentity · · Score: 4, Insightful

    [...] news of research that seems to confirm and support current theories of how cosmic rays are created. [...] The results lend support to the possibility of protons and nucleii being accelerated in supernova remnants to energies of 1 PeV (10^15 eV) and beyond. Here is the abstract from Nature.

    So this research confirms... supports...well lends support to the possibility. Care to soften it further?

  3. Re:When I punch 10^15 eV into Google... by the_brobdingnagian · · Score: 5, Informative

    Not if that's the energy of a single proton.

  4. According to the creation museum in Kansas by antifoidulus · · Score: 5, Funny

    they are created when God puts foil in his microwave :P

  5. Re:When I punch 10^15 eV into Google... by nukeade · · Score: 5, Informative

    It is, but it's all in one tiny particle (often a relativistic nucleus with all of its electrons stripped away). The energy density, then, is truly outrageous.

    ~Ben

  6. a good science post? by Goldsmith · · Score: 4, Insightful

    Give credit to cats-paw for giving us the link to the abstract for the original paper and to the editors for putting this up rather than a link to some half-baked pseudo-science blog about it.

    I think if I was not an experimentalist, I would want to study this area of physics (supernova observation). Going through the steps of a supernova exposes you to some of the most amazing physics we know of, and this research only adds to that.

    1. Re:a good science post? by Icarus1919 · · Score: 4, Funny

      I'm sorry, but I refuse to read science news unless it's been submitted by Roland.

  7. nuclei, NOT nucleii by Anonymous Coward · · Score: 5, Informative

    Stop trying to sound "smart" by ending words with "ii". To make Latin words ending "us" plural, remove the "us" and add ONLY ONE "i".

    "nucleus" -> "nuclei"

    "radius" -> "radii" (because there's already an "i" before the "us")

  8. Re:When I punch 10^15 eV into Google... by Bonker · · Score: 5, Informative
    For Comparison

    * 3.2×1011 joule or 200 MeV - total energy released in nuclear fission of one U-235 atom (on average; depends on the precise break up)
    * 3.5×1011 joule or 210 MeV - total energy released in fission of one Pu-239 atom (also on average)


    So, imagine the energy level to be 8-9 ORDERS OF MAGNITUDE (or around a billion times) more energetic than a nuclear fission chain reaction.
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  9. Re:When I punch 10^15 eV into Google... by Omnifarious · · Score: 5, Informative

    So, it takes 4.1868 joules to heat one cubic centimeter of water (one gram of water) one degree centigrade. So 0.00160217 joules is enough to heat one gram of water 383 microdegrees.

    So, yes, in one sense that's not very much energy.

    But, if you're going to scale the mass up, you should scale the energy up. So, it's one proton that has that much energy. The gram of water has approximately 6.02*10^23 proton masses. If every proton mass in the gram of water had that much energy, it would be equivalent to that gram of water being heated by 2.3*10^20 degrees. This is 230 trillion trillion degrees (yes, that's two trillions).

    I hope this gives you a sense of the scale involved here.

    When you have a single proton with enough energy to make a measurable difference in the temperature of a gram of water, you are talking an amazingly huge amount of energy.

  10. Re:Very, very hot by White+Flame · · Score: 5, Funny

    6,446,700,000,000,000,000 degrees! That's 6.4 billion billion degrees.

    But how many Libraries Of Congress On Fire is that?

  11. Re:When I punch 10^15 eV into Google... by MoxFulder · · Score: 4, Informative

    Indeed. The wikipedia article on ultra-high-energy cosmic rays has more info. The energy of such a particle is simply insane...

    Some of them apparently violate a theoretical limit on the energy of a particle that has traveled a long way across the universe... leading to the question of where exactly they come from.

  12. Re:When I punch 10^15 eV into Google... by Bonker · · Score: 4, Informative

    While the above poster is obviously in jest, it's worth pointing out the difficulties with his suggestion.

    The only way we currently have of energizing protons to even a measurable fraction of energy like this is in particle accelerators. They're spun around in magnetic fields to faster and faster speeds, gaining mass and energy or energy as they go. That energy ultimately comes from some kind of generator and the fuel it uses.

    Eventually, they're slammed into a stationary target or a particle going the other way in the same accelerator. The more mass and energy the particles have accumulated, the more exotic the reactions that occur when that happens. The point of the experiment is to funnel a massive amount of fuel energy into one spot and see what happens when it goes 'boom'.

    The super-energetic cosmic rays use the magnetic shockwave created by a Supernova to achieve about the same effect. Rather than being spun around a particle accelerator, they're being spun around the coiled loops of magnetic flux created when a super-massive star decides to disembowel itself.

    So, to get anywhere near the ability to create one of these, let alone some kind of ray weapon utilizing them, we'd need a particle accelerator larger than the Sun (or able to churn out more energy than the Sun does). By the time we were able to build one, we'd be dismantling planets by other means anyway.

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  13. Re:When I punch 10^15 eV into Google... by British · · Score: 4, Funny

    But it would take a year to charge the gun. Kinda cancels itself out.

  14. Re:God did it! by tm2b · · Score: 4, Funny

    God created everything from cosmic rays to herpes.
    But obviously, in different stages of the relationship.
    --
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