GUVI Level 3 Data Products
Aurora Data Products
What am I looking at?
Estimated electron mean energy (E0) and energy flux (Q) in the auroral oval
How were they produced?
There are a series of model runs and data processing to find the electron E0 and Q in the auroral region.
We first calculate E0 (0.5 to 20 keV) and Q (1 ergs/s/cm2) for precipitating electrons with a Gaussian or Maxwellian distribution. We do this by running B3C [Daniell et al., 1993] and AURIC [Strickland et al., 1999] models to get simulated GUVI LBHS and LBHL intensities at different look angles (0 -70 degrees). The simulated data are used to create lookup tables of the E0 versus the LBHL intensities and the ratios of LBHS and LBHL for each look angle. These lookup tables are used to estimate the E0 and Q from measured GUVI LBHS and LBHL intensities. See Strickland et al.  for details.
Read in GUVI L1B data and remove the dayglow contributions in the GUVI LBHS and LBHL data to obtain GUVI LBHS and LBHL intensities due to auroral particle precipitation.
Calculate the magnetic latitude (Mlat), longitude (Mlon) and local time (MLT) for each GUVI pixel with geographic latitude above 30 degrees.
Grid the dayglow-removed GUVI L1B data and look angles in the Mlat-MLT coordinates with a grid size of 0.44ºx0.44º in Mlat and Mlon or 50x50km. The ratio of gridded GUVI LBHS/LBHL and the look angle are used to search the tables created by B3C and AURIC runs to find the E0 and the LBHL intensity (reference LBHL) at the E0 in the tables. The Q in ergs/s/cm2 is obtained by calculating the ratio between the gridded GUVI LBHL and the reference LBHL. Interpolation is performed when it is necessary. To avoid large errors in the auroral products, E0 and Q are estimated only for the grids with LBHL and LBHS intensities above 200 Rayleighs. Currently, the lookup tables for Gaussian electrons are used.
Data Files – Available in both NetCDF and IDLsave files. On-line access for download.
Summary Images – Available in both PNG and PostScript files. On-line access for download.