Partial to full ring current evolution and energization during geomagnetic storms
Monday, 23 May 2016: 12:10 PM
Michael Denton1, Reinhard H Friedel2,3, Reeves Geoffrey1,2, Ruth M Skoug4, Brian Larsen2,3, Herbert O Funsten5, Harlan E. Spence6 and Seth G. Claudepierre7, (1)New Mexico Consortium, Space Science, Los Alamos, NM, United States, (2)Los Alamos National Laboratory, Los Alamos, NM, United States, (3)The New Mexico Consortium, Los Alamos, NM, United States, (4)Los Alamos Natl Lab, Los Alamos, NM, United States, (5)Los Alamos Natl Laboratory, Los Alamos, NM, United States, (6)University of New Hampshire Main Campus, Space Science Center, Durham, NH, United States, (7)Aerospace Corporation, Los Angeles, CA, United States
Abstract:
It is generally acknowledged that the ring current develops from medium energy ions and electrons (few keV) in the plasma sheet and that this population is energized during enhanced geomagnetic activity. The source plasma is delivered to the inner magnetosphere during periods of enhanced convection, upon which energization takes place. We present observations of the transition from partial ring current to circular ring current the and energization during geomagnetic storms, both statistically and for particular events. Measurements of the ion composition from the HOPE instruments on Van Allen Probes (O+, H+, He+), and of ions and electrons from the MagEIS instruments, demonstrate a complex evolution of the ring current as geomagnetic storms evolve. Our results confirm the energization of the source population during storms, quantify the energization as a function of L and MLT, and also provide the composition ratios as a function of energy - all essential factors in modeling/predicting ring current development. Further, we attempt to pinpoint both the location in L and MLT and timing of the partial to full ring current transition using the two spacecraft measurements of the Van Allen Probe Mission.It is generally acknowledged that the ring current develops from medium energy ions and electrons (few keV) in the plasma sheet and that this population is energized during enhanced geomagnetic activity. The source plasma is delivered to the inner magnetosphere during periods of enhanced convection, upon which energization takes place. We present observations of the transition from partial ring current to circular ring current the and energization during geomagnetic storms, both statistically and for particular events. Measurements of the ion composition from the HOPE instruments on Van Allen Probes (O+, H+, He+), and of ions and electrons from the MagEIS instruments, demonstrate a complex evolution of the ring current as geomagnetic storms evolve. Our results confirm the energization of the source population during storms, quantify the energization as a function of L and MLT, and also provide the composition ratios as a function of energy - all essential factors in modeling/predicting ring current development. Further, we attempt to pinpoint both the location in L and MLT and timing of thr partial to full ring current transition using the two spacecraft measurements of the Van Allen Probe Mission.
