Magnetosphere Seminars

2014 - Fall Schedule

June 23, 2014 – “The role of cold plasma in the magnetosphere: Plasmaspheric drainage plumes and refilling from the ionosphere”

Speaker:   Mick Denton (SSI & Lancaster, UK)
Date & Time:   June 23, 2014 ,  4:00 PM Location: LASP Space Science Building, room N248 upstairs.
Abstract:  

The role that cold ionospheric plasma plays in magnetospheric dynamics remains poorly understood. The cold population overlaps with more energetic plasmas (e.g. radiation belts) where wave-particle interactions can play an important role. Observations from geosynchronous orbit show that high density (~100 cm-3) plasmaspheric drainage plumes are frequently detected whenever magnetospheric convection is elevated. In many… Read more »

Aug 12, 2014 – “Estimates of ULF Wave Radial Diffusion of Relativistic Electrons in the Radiation Belts using the Van Allen Probes, THEMIS and GOES”

Speaker:   Theodore Sarris (LASP & Democritus University, Greece)
Date & Time:   August 12, 2014 ,  4:00 PM Location: LASP Space Science Building, room N100 (Different to usual room).
Abstract:  

Ultra-Low Frequency (ULF) waves are critical in radial diffusion processes of relativistic electrons in the radiation belts, and their Power Spectral Density as a function of L, together with their mode number, are an integral part of the radial diffusion coefficients and of assimilative models of the radiation belts. Using simultaneous measurements from two GOES… Read more »

Sept 23, 2014 – “Dynamic Geomagnetic Field Maps: Blending Observation and Theory in Space Weather Operations”

Speaker:   E. Joshua Rigler (U.S.G.S.)
Date & Time:   Sept. 23, 2014 ,  4:00 PM Location: LASP Space Science Building, room N100 (1st floor).
Abstract:  

Spherical elementary current systems (SECs; a NASA implementation of Amm & Viljanen’s seminal work) are fit to USGS real time magnetic observatory measurements, then used to generate contiguous time-varying maps of ground-level magnetic fields across the continental United States. These maps will eventually be used/disseminated by NOAA’s Space Weather Prediction Center as a geomagnetically induced… Read more »

Sept 30, 2014 – “Understanding the Role of EMIC Waves in the Dynamics of Relativistic and Ultra-relativistic Electron Populations”

Speaker:   M.E. Usanova (LASP)
Date & Time:   Sept. 30, 2014 ,  4:00 PM Location: LASP Space Science Building, room N100 (1st floor).
Abstract:  

Electromagnetic ion cyclotron (EMIC) waves are believed to be important for influencing the dynamics of energetic particles in the inner magnetosphere, especially in relation to ring current and radiation belt dynamics. EMIC waves often grow as a result of perpendicular temperature anisotropy, with the ion dynamics and energy and pitch angle distributions in the ring… Read more »

Oct 07, 2014 – “An impenetrable barrier to ultra-relativistic electrons in the Van Allen radiation belts”

Speaker:   Dan Baker (LASP)
Date & Time:   Oct. 07, 2014 ,  4:00 PM Location: LASP Space Science Building, room W120 (1st floor).
Abstract:  

The energy distribution, spatial extent and particle species makeup of the Van Allen belts has been explored by several space missions. However, recent observations by the NASA dual-spacecraft Van Allen Probes mission have revealed wholly unexpected properties of the radiation belts, especially at highly relativistic (E > 2 MeV) and ultra-relativistic (E > 5 MeV)… Read more »

Oct 28, 2014 – ” Perils of Using Least Squares”

Speaker:   Ashar Ali (LASP)
Date & Time:   Oct. 28, 2014 ,  4:00 PM Location: LASP Space Science Building, room N100 (1st floor).
Abstract:  

Method of least squares is the most popular method of fitting a given model to data. While the method has several advantages, such as a reasonable computational complexity, a closed form solution which is unique and guaranteed to exist in the linear case, and widespread availability of fast and efficient algorithms/implementations, it has two severe… Read more »

Nov 04, 2014 – “Local time variations in Jupiter’s M-I coupling”

Speaker:   L.C. Ray (UCL)
Date & Time:   Nov. 04, 2014 ,  3:45 PM Location: LASP Space Science Building, room N100 (1st floor).
Abstract:  

The ionization of neutral material ejected by Jupiter’s volcanically active moon, Io, results in a plasma disc that extends from Io’s orbit out through the jovian magnetosphere. This magnetospheric plasma is coupled to the planetary ionosphere via currents which flow along the magnetic field. Inside of ~40 jovian radii, these currents transfer angular momentum from… Read more »

Nov 11, 2014 – “Global Views of Magnetic Perturbations from ST5, DMSP and AMPERE Spacecraft: Response to Solar Wind Driving”

Speaker:   Delores Knipp (CU/NCAR)
Date & Time:   Nov. 11, 2014 ,  4:00 PM Location: LASP Space Science Building, room N100 (1st floor).
Abstract:  

In this talk I will discuss new efforts to validate and standardize low earth orbit magnetometer measurements from commercial and research satellites operating during the last decade–the Iridium constellation, Defense Meteorological Satellite Program (DMSP) Spacecraft, Space Technology 5 and the Iridium constellation.  As examples, I will show reprocessed magnetometer data from all of these missions. … Read more »

Nov 18, 2014 – “Jupiter’s polar cap aurora: The swirl region”

Speaker:   Denis Grodent (University of Liège)
Date & Time:   Nov. 18, 2014 ,  4:00 PM Location: LASP Space Science Building, room N100 (1st floor).
Abstract:  

2014 DPS Talk Extended

Nov 19, 2014 – “The Martian Ionosphere and Induced Magnetosphere, studied with Mars Express”

Speaker:   D. Andrews (IRFU)
Date & Time:   Nov. 19, 2014 ,  1:00 PM Location: LASP Space Science Building, room W120 (1st floor).
Abstract:  

Because of the lack of an active dynamo, Mars does not posses a dipolar magnetic field capable of forming a magnetospheric cavity like that found at Earth.  Instead, the solar wind interacts directly with the upper atmosphere and ionosphere of the planet. A ‘draped’ or ‘induced’ magnetosphere is formed, which rapidly alters with changing solar… Read more »