• Thursday, September 1, 2016 -
    3:30pm to 4:30pm
     ·  Space Science Seminar
    Federico Fraschetti, University of Arizona, Tucson, AZ

    Abstract: Collisionless shocks are regarded as the major source of those energetic particles spread over several orders of magnitude in rigidity that are called cosmic-rays. In-situ measurements of interplanetary shocks offer a unique opportunity of probing the process of particle acceleration at the shock, or in the vicinity of the shock, by measuring the particle intensity and the magnetic field.

  • Wednesday, August 17, 2016 -
    3:00pm to 4:00pm
     ·  Space Science Seminar
    Michael Hirsch, Boston University Center for Space Physics

    Abstract: A new generation of geospace instruments are pushing beyond prior observational limitations, fueled by technology developments in all sectors over the past decade. These technological advances drive automated long-term high-bandwidth data recording networks for instruments of all types. In particular, we discuss the benefits, challenges, and solution for experiments incorporating high-speed (50+ frames/sec) EMCCD and sCMOS camera networks at 200 GB/hour/camera.

  • Wednesday, August 10, 2016 -
    3:00pm to 4:00pm
     ·  Space Science Seminar
    Denny M. Oliveira

    Abstract: Geomagnetic storms have been known to be the cause of upper atmosphere heating and neutral density upwelling since the beginning of the space era. Early Sputnik observations during storm times showed that thermospheric heating was the cause of increase in air drag forces which in turn affected satellite accelerations. In the following years, such observations inspired other LEO (low Earth orbit) missions that were life short due to air drag which in turn gave basis to the development of thermospheric empirical models, e.g., NRLMSIS-00 and Jacchia-(Bowman) models.

  • Thursday, July 14, 2016 -
    10:00am to 11:00am
     ·  Space Science Seminar
    Farzane Shirazi

    Abstract: The objective of the proposed work is investigation of channeling and concentrating soft gamma rays (above 100 keV) using multilayer thin films of alternating low and high-density materials. This will enable future telescopes for higher energies with the same mission parameters already proven by NuSTAR. Based on initial investigations at Los Alamos National Laboratory (LANL) we are investigating producing these multilayers with the required thicknesses, uniformity and smoothness using magnetron sputter (MS) and pulsed laser deposition (PLD) techniques.

  • Thursday, May 26, 2016 -
    3:30pm to 4:30pm
     ·  Space Science Seminar
    Jerry Goldstein, Southwest Research Institute

    Abstract: 

  • Wednesday, May 25, 2016 -
    3:00pm to 4:00pm
     ·  Space Science Seminar
    Shri Kanekal, NASA Goddard Space Flight Center

    Abstract: Since the discovery of the Earth’s radiation belts by James Van Allen in the 1950s, they have been well studied providing a laboratory for understanding charged particle dynamics in the heliosphere and beyond. The Van Allen belts, comprise charged particles trapped in the geomagnetic field, usually confined to two distinct regions, the inner and the outer belt separated by the so-called slot region.

  • Wednesday, April 27, 2016 - 3:00pm  ·  Space Science Seminar
    Dr. Ningyn Liu, Florida Institute of Technlogies

    Abstract: Thunderstorms and lightning can produce strong impact on the D region (60-100 km) of the ionosphere. The most impressive display of this impact is the occurrence of transient luminous events such as sprites and halos caused by lightning. Recent studies show that the D region ionospheric density can be briefly increased by many orders of magnitude due to extremely intense lightning. On the other hand, it has also been found that moderate variation of the lower ionosphere on a timescale of minutes to hours is correlated with electrical activity in thunderstorms.

  • Wednesday, April 20, 2016 -
    4:00pm to 5:00pm
     ·  Space Science Seminar
    Kristopher G. Klein, UNH

    Abstract:  Characterizing the nature of the dissipation of turbulent, electromagnetic fluctuations remains a significant challenge in understanding a number of heliospheric processes, including coronal heating and the acceleration of the solar wind. A number of dissipation mechanisms have been proposed, which can be broadly classified as coherent, such as Landau, cyclotron, and transit-time damping, incoherent, such as stochastic heating, and interactions occurring in intense, spatially intermittent structures.

  • Wednesday, April 13, 2016 -
    3:00pm to 4:00pm
     ·  Space Science Seminar
    Dr. Eric Grove, Naval Research Laboratory

    Abstract: Since its launch in 2008, the Fermi Gamma-ray Space Telescope has revolutionized gamma-ray astrophysics, transforming our understanding of the high-energy universe.  Its primary instrument, the Large Area Telescope (LAT), surveys the gamma-ray sky above 20 MeV with a sensitivity at least a factor of 30 better than its predecessor, EGRET on the Compton Gamma Ray Observatory.  This improvement was made possible by a novel design using modern solid-state detectors and scintillators, and was realized by scientists and engineers in five countries working over a period

  • Thursday, March 31, 2016 - 3:00pm  ·  Space Science Seminar
    Brant Carlson, Carthage College in Wisconsin

    Abstract:  The conductive lightning channel is only a centimeter or so in diameter.  Charge deposited along such a narrow channel produces a large radial electric field, producing corona discharge in nearby air that carries the charge outward several meters.  The formation of this "corona sheath" affects a wide range of observable properties of lightning, including the overall charge carried by the channel, the shape, speed, and attenuation of impulsive currents, and the possibility of x-ray production.  This talk discusses such effects and introduces a simplified model of