A Relation Between the Auroral X-Ray Total Intensity and the Substorms Index-AE

Abstract

In this short report a new aurora intensity index (AI) is defined as the total X‐ray intensity derived from the images obtained by the aurora X‐ray camera of PIXIE on board the Polar satellite. We found a linear relationship between the magnetosphere sub‐storm index (AE) and the new aurora intensity index (AI). Among the 83 data sets chosen from 1997 to 2001, 56.6% of which has the linear correlation coefficients larger than 0.60 (the maximum is 0.97). We suggest that auroral X‐ray intensity (AI) is a candidate of a new real‐time index obtained from satellite observations for monitoring magnetosphere sub‐storms.