News & Events

  • Seeking the generation mechanism for Bursty radio emissions from Earth's ionosphere

    April 2, 2014

    For almost twenty years, bursty radio emissions at 1.5-4.5 MHz, originating in Earth's high latitude ionosphere, have been described and probed with multiple experiments. The emission mechanism remains a mystery, though recently a theory has been proposed. We have set up arrays of antennas attached to sensitive digital receivers at several Arctic and Antarctic locations, to perform measurements needed to test the theory. In addition, we are investigating signals similar to the burst emissions detected by NASA satellites.

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  • Polarization, fine structure and occurrence rates of ground-level AKR

    April 2, 2014

    Auroral Kilometric Radiation is the most powerful natural radio emission from Earth's environment, carrying away up to a percent of the energy of the aurora. Our group and others have found evidence that the radiation is not only beamed away from the Earth, as previously known, but occasionally leaks to low altitudes.

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  • Simulations of whistler chorus waves

    April 2, 2014

    Electromagnetic ion cyclotron and whistler chorus waves occur in the Earth's inner magnetosphere at a distance of about 4 to 7 Earth radii from the Whistler chorus waves occur in the Earth's inner magnetosphere at a distance of about 4 to 7 Earth radii from the center of the earth. These waves are thought to provide a mechanism for energization and loss of particles in the Earth's radiation belt. Two-dimensional simulations of these waves are revealing the structure of the waves, their evolution, and their effects on particle populations including the radiation belts.

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  • BARREL (Balloon Array for RBSP Relativistic Electron Losses)

    April 1, 2014

    BARREL uses stratospheric balloons to study the loss of high energy electrons from Earth's Van Allen radiation belts. The electrons in this region of near-Earth space are relativistic, moving very close to the speed of light. BARREL balloons measure x-rays produced by these particles when they are scattered into Earth's atmosphere. BARREL balloon campaigns have been conducted in Antarctica in January-February 2013 and 2014 during which 20 small (~20 kg) balloon payloads were launched, and in Sweden in 2015 (7 launches).

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  • Quantum Simulation with Cold Atoms in Engineered Optical Potentials

    April 1, 2014

    Many-body quantum systems can be very difficult to handle theoretically, and in some important cases the true nature of the phase diagram is not yet accurately known. One possible path to gain deeper understanding of these incredibly rich physical systems is to engineer a "synthetic" many body quantum system that maps onto a particular system of interest, but has more conveniently tunable properties. Ultracold atoms in engineered optical potentials are one platform for such an approach.

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