The Role and Contributions of Energetic Neutral Atom (ENA) Imaging in 
Magnetospheric Substorm Research

C.J. Pollock, P. C:son-Brandt, J.L. Burch, M.G. Henderson, J.-M. Jahn, 
D.J. McComas, S.B. Mende, D.G. Mitchell, G.D. Reeves, E.E. Scime, R.M. Skoug, 
M. Thomsen and P. Valek


Energetic Neutral Atom (ENA) imaging has contributed substantially to substorm
research. This technique has allowed significant advances in areas such as
observation and quantification of injected particle drift as a function of
energy, observation of dynamics in the tail that are directly related to the
effects of imposed (growth phase) and induced (expansion phase) electric fields
on the plasma, the prompt extraction of oxygen from the ionosphere during
substorms, the relationship between storms and substorms, and the timing of
substorm ENA signatures. We present discussion of the advantages and
shortcomings of the ENA technique for studying space plasmas. Although the
technique is in its infancy, it is yielding results that enrich our
understanding of the substorm process and its effects.

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Space Science Reviews, 109, No. 1-4, p. 155-183, 2003