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Gamma Rays From Thunderclouds

KentuckyFC sends us a report of gamma rays detected at a Japanese nuclear plant, whose origin was thunderclouds high overhead (abstract, article PDF). The theory is that showers of electrons caused by cosmic rays, when they encounter the high electric fields present in thunderstorm clouds, can be accelerated to energies above 10 MeV and result in bremsstrahlung photons detectable on the ground.

4 of 104 comments (clear)

  1. Comment removed by account_deleted · · Score: 2, Interesting

    Comment removed based on user account deletion

  2. Re:Wow. That's some high energy Gamma Rays by mefein · · Score: 2, Interesting
    Terrestrial Gamma-ray Flashes were discovered in 1994 by BATSE - a space based experiment that operated in the 90's. They are quite common (several per day). It is amazing that there are such efficient accelerators in the Earths atmosphere.

    GLAST , is a new gamma-ray mission which will launch early next year and will have the capability to measure TGFs up to much higher energies -- so we will get to really understand the acceleration mechanism. Both instruments on GLAST are designed to observe the celestial sky, but they have such large fields of view that they can also simultaneously make observations of the Earth for at least some of the time.

  3. Radiation Overdose? by soccer_Dude88888 · · Score: 1, Interesting

    If thunderclouds can accelerate radiation energy, how come I never heard of people died in places where there are lots of thuderstorm activities due to radiation overdose?

    Besides, even though there is no thunderstorm, cosmic rays can generate energy up to 1GeV.

    1. Re:Radiation Overdose? by ZombieWomble · · Score: 2, Interesting
      Humans are much more tolerant to (relatively) small amounts of radiation than people often think. Depending on where you live, your average yearly dose can vary by almost a factor of 1,000 - the relative dose from such events in thunderstorms is much less than this variation in background, given how little is produced by any given event.

      Also, while 1GeV is a typical cosmic ray energy, they can go much much higher. The "Oh my god" particle had an energy of around 50 Joules. That's comprable to a well-hit tennisball, which is a whopping amount of energy for a subatomic particle.