12,000

We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK

93%

93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Global view of refilling of the plasmasphere
View graph of relations

« Back

Global view of refilling of the plasmasphere

Research output: Contribution to journalJournal article

Published

Journal publication date09/2007
JournalGeophysical Research Letters
Journal numberL17102
Volume34
Number of pages5
Pages1-5
Original languageEnglish

Abstract

We use observations by the IMAGE Extreme Ultraviolet Imager (EUV) to characterize the outflow of He+ from the ionosphere to the plasmasphere under quiet conditions. The view afforded by the IMAGE orbit encompasses the entire plasmasphere in a single exposure, enabling us to examine for the first time the globally-averaged properties of plasmasphere refilling. We focus on a study period that begins with a moderate erosion event, and follow refilling during multiple orbits for a period of 69 hours. The inferred volume refilling rate, averaged over azimuth and time, ranges from ∼1 He+ cm−3 h−1 at L = 3.3 to ∼7 × 10−2 He+ cm−3 h−1 at L = 6.3 and is generally consistent with earlier, more local measurements. We show that the measured radial abundance profiles match those predicted by the Sheffield University Plasmasphere Ionosphere Model (SUPIM) for 2 ≤ L ≤ 4.