Spatial and temporal properties of AKR burst emission derived from Cluster WBD VLBI studies

• Main Authors: R. L. Mutel, D. A. Gurnett, I. W. Christopher
• Format: Article
• Language: English
• Published: Copernicus Publications 2004-07-01
• Series: Annales Geophysicae
• Online Access: https://www.ann-geophys.net/22/2625/2004/angeo-22-2625-2004.pdf

We have determined the locations of over 6000 individual auroral kilometric radiation (AKR) bursts between July 2002 and May 2003 using a very long baseline interferometer (VLBI) array. Burst locations were determined by triangulation using differential delays from cross-correlated Cluster WBD waveforms. Typical position uncertainties are 200-400km in the plane normal to the source-spacecraft line, but much larger along this line. The AKR bursts are generally located above the auroral zone with a strong preference for the evening sector (22:00 MLT±2h). However, a few epochs imaged during the austral summer have loci in the daytime sector, especially near 15:00 MLT. There is marginal evidence for a small N-S hemispheric asymmetry in mean MLT and invariant latitude.