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Creators/Authors contains: "Kasahara, K."

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  1. ; ; ; ; ; ; ; ; ; ; et al (, Science)
    Smith, KT (Ed.)
    Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle’s energy as 244 ± 29   stat .   − 76 + 51 syst .  exa–electron volts (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics. 
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  2. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review Letters)
  3. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review D)
  4. ; ; ; ; ; ; ; ; ; ; et al (, Astroparticle Physics)
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  5. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review D)
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  6. ; ; ; ; ; ; ; ; ; ; et al (, Geophysical Research Letters)
    Abstract In this paper, we present the first high‐speed video observation of a cloud‐to‐ground lightning flash and its associated downward‐directed Terrestrial Gamma‐ray Flash (TGF). The optical emission of the event was observed by a high‐speed video camera running at 40,000 frames per second in conjunction with the Telescope Array Surface Detector, Lightning Mapping Array, interferometer, electric‐field fast antenna, and the National Lightning Detection Network. The cloud‐to‐ground flash associated with the observed TGF was formed by a fast downward leader followed by a very intense return stroke peak current of −154 kA. The TGF occurred while the downward leader was below cloud base, and even when it was halfway in its propagation to ground. The suite of gamma‐ray and lightning instruments, timing resolution, and source proximity offer us detailed information and therefore a unique look at the TGF phenomena. 
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  7. ; ; ; ; ; ; ; ; ; ; et al (, Journal of Geophysical Research: Atmospheres)
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  8. ; ; ; ; ; ; ; ; ; ; et al (, Physical Review D)
  9. ; ; ; ; ; ; ; ; ; ; et al (, The Astrophysical Journal)
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  10. ; ; ; ; ; ; ; ; ; ; et al (, The Astrophysical Journal)
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