83 research outputs found

    Resolving the strange behavior of extraterrestrial potassium in the upper atmosphere

    Get PDF
    It has been known since the 1960s that the layers of Na and K atoms, which occur between 80 and 105 km in the Earth's atmosphere as a result of meteoric ablation, exhibit completely different seasonal behavior. In the extratropics Na varies annually, with a pronounced wintertime maximum and summertime minimum. However, K varies semiannually with a small summertime maximum and minima at the equinoxes. This contrasting behavior has never been satisfactorily explained. Here we use a combination of electronic structure and chemical kinetic rate theory to determine two key differences in the chemistries of K and Na. First, the neutralization of K+ ions is only favored at low temperatures during summer. Second, cycling between K and its major neutral reservoir KHCO3 is essentially temperature independent. A whole atmosphere model incorporating this new chemistry, together with a meteor input function, now correctly predicts the seasonal behavior of the K layer

    Biofilm mediated decontamination of pollutants from the environment

    No full text

    Operations of and Future Plans for the Pierre Auger Observatory

    No full text
    Contributions to the 31st ICRC, Lodz, Poland, July 2009International audienceTechnical reports on operations and features of the Pierre Auger Observatory, including ongoing and planned enhancements and the status of the future northern hemisphere portion of the Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009

    Astrophysical Sources of Cosmic Rays and Related Measurements with the Pierre Auger Observatory

    No full text
    Studies of the correlations of ultra-high energy cosmic ray directions with extra-Galactic objects, of general anisotropy, of photons and neutrinos, and of other astrophysical effects, with the Pierre Auger Observatory. Contributions to the 31st ICRC, Lodz, Poland, July 2009

    Calibration and Monitoring of the Pierre Auger Observatory

    No full text
    Reports on the atmospheric monitoring, calibration, and other operating systems of the Pierre Auger Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009

    The Cosmic Ray Energy Spectrum and Related Measurements with the Pierre Auger Observatory

    No full text
    Studies of the cosmic ray energy spectrum at the highest energies with the Pierre Auger Observatory
    corecore