Comparisons of TWINS Observations with CIMI Calculations during ion
injections on 29th June 2013
Abstract
In a recent study by Shekhar et. al. 2021, a moderate geomagnetic storm
(sym-H$\sim$-100 nT) during 28th-29th June 2013 was
studied using CIMI (Comprehensive Inner Magnetosphere-Ionosphere)
simulations and results were compared with TWINS (Two wide-angle Imaging
Neutral-atom Spectrometers) observations. The CIMI simulations did not
include ion injections. As a result, TWINS and CIMI results were found
to disagree on the number and locations of ion pressure peaks and ion
drift patterns. In this study, CIMI simulations were performed with the
inclusion of ion injections using the geosynchronous particle flux data
from 6 LANL satellites as boundary conditions. Comparisons of the
spatial and temporal evolution of ring current (RC) ions including ion
pressure, anisotropy, intensity and median energy, the ion spectrum at
the ion pressure peak locations show improved agreements with TWINS
observations, specifically in the recovery phase post 06 UT on 29th
June, when rapid AE index fluctuations were observed.