Energetic electrons (≥50 keV) are injected into the slot region (2 < L < 4) between the inner and outer radiation belts during the early recovery phase of geomagnetic storms. Enhanced convection from the plasma sheet can account for the storm-time injection at lower energies but does not explain the rapid appearance of higher-energy electrons (≥150 keV). The effectiveness of either radial diffusion (driven by enhanced ULF waves) or local acceleration (during interactions with enhanced whistler mode chorus emissions), as a potential source for refilling the slot at higher energies, is analyzed for observed conditions during the early recovery phase of the 10 October 1990 storm. We demonstrate that local acceleration, driven by observed chorus emissions, can account for the rapid enhancement in 200–700 keV electrons in the outer slot region near L = 3.3. Radial diffusion is much less effective but may partially contribute to the flux enhancement at lower L. Subsequent outward expansion of the plasmapause during the storm recovery phase effectively terminates local wave acceleration in the slot and prevents acceleration to energies higher than ∼700 keV. A statistical analysis of energetic electron flux enhancements and wave and plasma properties over the entire CRRES mission supports the concept of local wave acceleration as a dominant process for refilling the slot during the main and early recovery phase of storms. For moderate storms, the injection process naturally becomes less effective at energies ≥1 MeV, due to the longer wave acceleration times and additional precipitation loss from scattering by electromagnetic ion cyclotron waves. However, during extreme events when the plasmapause remains compressed for several days, conditions may occur to allow wave acceleration to multi-MeV energies at locations normally associated with the slot.
Back to overview,Home naval-today GWCSG Begins Their Portion of Talisman Saber 2013 July 16, 2013 U.S. and Royal Australian Navy (RAN) Sailors from the George Washington Carrier Strike Group (GWCSG) began their portion of Talisman Saber 2013 off the northeast coast of Australia, July 15.Exercise Talisman Saber 2013 is a biennial training activity aimed at improving Australian and U.S. combat readiness and interoperability.“Talisman Saber 2013 demonstrates the U.S. and Australian commitment to enhancing security, peace and stability in the Indo-Asia-Pacific region,” said Rear Adm. Mark Montgomery, the commander of GWCSG. “Our alliance with Australia is solidly grounded in our shared values and common security concerns and approaches. We coordinate closely with our Australian partners to promote security throughout the region.”Over the next two weeks the GWCSG will participate in various events with their RAN partners including air-defense warfare, anti-submarine warfare, surface warfare, visit, board, search and seizure, air-to-air training, and close-air support to amphibious forces.“This exercise provides effective and intense training to ensure our forces are capable, interoperable, and deployable on short notice” said Montgomery. “It increases the ability of all participants to plan, coordinate and execute complex operations.”Participants from the GWCSG include Nimitz-class aircraft carrier USS George Washington (CVN 73) with embarked Carrier Air Wing 5, embarked Commander Destroyer Squadron 15, Ticonderoga-class guided-missile cruiser USS Antietam (CG 54), Arleigh-burke class guided-missile destroyers USS Lassen (DDG 82), USS Preble (DDG 88), USS Momsen (DDG 92), USS Chung-Hoon (DDG 93), and the RAN guided-missile frigate HMAS Sydney (FFG 03).[mappress]Press Release, July 16, 2013; Image: US Navy Training & Education GWCSG Begins Their Portion of Talisman Saber 2013 Share this article