Table of Contents ====================================================================== 1. 2014 WORKSHOP REPORT: Inner Magnetosphere Cross-Energy/Population Interactions Focus Group Report Focus Group 2. SCOSTEP Visiting Scholar (SVS) Program ====================================================================== *************************** ** THE GEM MESSENGER ** *************************** Volume 24, Number 33 October 15, 2014 ---------------------------------------------------------------------- 1. 2014 WORKSHOP REPORT: Inner Magnetosphere Cross-Energy/Population Interactions Focus Group Report Focus Group ---------------------------------------------------------------------- From: Yiqun Yu, Colby Lemon , Michael Liemohn, and Jichun Zhang The Inner Magnetosphere Cross-Energy/Population Interactions (IMCEPI) Focus Group began its first year at the 2014 GEM Summer Workshop in Portsmouth, Virginia. The broad scientific goals of the focus group are, through implementation of physics in existing models, to contribute to the physics-based understanding of the mechanisms responsible for the ring current growth and decay by exploring the interactions among the various particle populations and the feedback mechanisms that regulate them. Some specific questions to be addressed are 1) How do the cold plasmasphere and hot ring current particles influence wave-particle interactions? 2) How do the cross-energy/population interactions alter the inner magnetospheric dynamics? 3) How does particle precipitation change ionosphere conductivity and feed back on the inner magnetosphere dynamics? Two sessions were held on Thursday afternoon, and one on Friday morning. The first session targeted the influence of plasmasphere/ring current populations on wave excitation and particle distribution, and feedback on these populations. The purpose of this session was to build on what was learned from the past Focus Group "Plasmasphere- Magnetosphere Interaction" and apply that to couple the plasmasphere with the higher-energy populations, and continue the discussion on the coupling between the plasmasphere, waves, and ring current. Eun-Hwa Kim reported a method to infer heavy ion concentration ratios from EMIC wave observations that result from ion-ion hybrid (IIH) resonance. The sensitive dependence of the frequency of a compressional wave driver on the heavy ion concentration makes it possible to estimate the heavy ion concentration ratio. Although wave absorption occurs for a wide range of heavy ion concentrations, it only occurs for a limited range of field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. The wave absorption and observed EMIC waves from GOES-12 satellite are used to demonstrate how this technique can be utilized to estimate that the He+ concentration is around 4% near L=6.6. Robert Allen presented an analysis of cluster data and statistical maps of EMIC occurrence rates, showing patterns interpreted as occurrence due to three primary source regions: dayside at high L- shells due to magnetospheric compressions, off-equatorial dayside regions due to Shabansky orbits, and regions where anisotropic ring current populations overlap with plasmaspheric plumes. In a separate talk the next morning, he presented a related analysis of plasma data showing linear theory derived wave growth parameters that predict EMIC instability in the same regions. Anthony Saikin presented statistical results from Van Allen Probes magnetometer data that separated the H+, He+, and O+ EMIC bands. Their results showed that proton-band waves are observed in the dusk region, helium-band waves are relatively uniform in MLT, and Oxygen-band are primarily observed in localized pre-noon, pre-dawn, and dusk regions. Justin Lee presented results from the application of THEMIS low-energy ion composition statistics to EMIC wave observations and modeling. Using measurements by multiple THEMIS spacecraft, they analyzed four typical EMIC wave events in the four MLT sectors and consider the properties of both cold and warm ions supplied from previous statistical studies to interpret the wave observations using linear theory. Xiangrong (Sean) Fu presented PIC simulations of banded chorus excitation using RBSP HOPE data. Based on observed parameters, linear kinetic theory shows that with enhanced temperature anisotropies, both bands of whistler waves can be excited. PIC simulation results show whistler waves and “banded” electric field spectra are excited and late-time temperature anisotropies approach observed values. Vania Jordanova presented recent results from the RAM-SCB model and comparisons with Van Allen Probes data, highlighting the effects of EMIC and Chorus wave-particle interactions on the energy and pitch- angle distributions. In a follow-up the next morning, she showed that RAM-SCB simulations predict strong EMIC wave amplitudes and proton precipitation in locations that agree well with IMAGE/FUV proton auroral data. David Mackler showed statistical results from IMAGE MENA and suggested that precipitation of plasma sheet and partial ring current ions are the dominant driver of low altitude emission of ENAs. The second session addressed the coupling of ring current plasma with electric and magnetic fields via MI coupling and self-consistent treatment of the magnetic field. Raluca Ilie gave an update on the status of coupling between the HEIDI inner magnetosphere model and the BATS-R-US global MHD model, comparing results from idealized simulations with one-way and two-way coupling. Christian Ferradas presented Cluster CODIF data of events in which He+ or O+ ions were the dominant ion species, and explained these observations by using drift trajectories in simple field models, including charge exchange losses. Yiqun Yu simulated ring current particle injections using the Space Weather Modeling Framework with the RAM-SCB model, emphasizing the importance of a self-consistent treatment of substorm injections that includes the dipolarization of the magnetic field and the induced electric fields. Jiang Liu discussed the physics of dipolarizing flux bundles (plasma bubbles) and demonstrated their identification inside of geosynchronous orbit with THEMIS magnetometer data (where they can be difficult to identify using only flow speed). The third session, on Friday morning, aimed to improve the full self- consistent link between the wave-particle interactions, particle precipitation, and ionospheric conductivity models. Mike Liemohn presented a statistical analysis of plasmapause location data during storms from 2000-2002 that were obtained through an automated analysis of IMAGE EUV data. Superposed epoch analyses were used to contrast plasmapause behavior during Magnetic Cloud, ICME- Sheath, and CIR-Driven storms, and these responses were related back to the properties of the upstream drivers. Binzheng Zhang presented numerical experiments with the LFM model that compared different ionospheric conductance models in an effort to explain the clockwise tilt of the ionospheric convection cells, and suggested that the typical meridional gradients in the Hall conductance drive the clockwise rotation and a duskward shift of the nightside reconnection region and flow channels. Hyunju Connor simulated a storm with the OpenGGCM coupled with the CTIM model, and showed that they were able to reproduce high-latitude neutral density peaks seen in CHAMP and GRACE observations caused by neutral upwelling of the thermosphere due to joule heating. Colby Lemon compared the effects of different electron pitch-angle scattering models in RCM-E simulations of a magnetic storm, demonstrating significant differences in the ring current buildup for both electrons and protons due to feedback on the electric field caused by auroral conductance enhancements. Because of the focus on extensive coupling processes, and the interconnectedness of those processes, many of the talks and the resulting discussion during each session touched on multiple subjects and highlighted the complexities involved in quantitatively modeling a coupled system with so much feedback. After the talks, there was discussion of how to communicate throughout the year by creating an IMCEPI email list and posting information to the GEM Wiki. We also discussed some challenge events for the GEM Mini-Workshop, such as the 17 March 2013 and 1 June 2013 magnetic storm. Finally, we discussed holding a joint session at the 2015 Summer Workshop with the Quantitative Assessment of Radiation Belt Modeling focus group, focusing on the wave-particle interactions and coupling with the radiation belts. ---------------------------------------------------------------------- 2. SCOSTEP Visiting Scholar (SVS) Program ---------------------------------------------------------------------- From: Maura Hagan Dear colleagues, The Scientific Committee on Solar-Terrestrial Physics (SCOSTEP) announces the establishment of a new capacity building activity, the SCOSTEP Visiting Scholar (SVS) program. In the paragraphs below we describe our vision for SVS and solicit your help in the identification of institutional partners for the SVS program implementation plan. As you may know, SCOSTEP is an interdisciplinary body of the International Council for Science, which strives to bring together different scientific disciplines to address scientific issues of international relevance. The SVS program will complement the current scientific program and public outreach activities of SCOSTEP. The objective of the SVS program is to provide training to young scientists and graduate students from developing countries in well- established solar terrestrial physics laboratories, for periods of between one and three months. Our aim is to fund four scholars each year, one related to each of the four SCOSTEP VarSITI themes (http://www.varsiti.org/). The training will help the young scientists to advance their career in solar terrestrial physics using the technique/skill they learned during the training. SCOSTEP will provide the airfare, while it is expected that the hosting lab will provide the living expenses (lodging, meals, ground transportation, visa fees and other incidentals). Trainees should have their own health insurance or arrange a provision with the host lab. We envision that the SVS process will operate in conjunction with existing visiting scientist schemes with similar aims, whether organized by individual laboratories or other programs. For the first call therefore, we wish to identify existing schemes that would be willing to partner with SVS in this capacity building effort. Please contact the SCOSTEP Scientific Secretary Marianna Shepherd (mshepher@yorku.ca) to register your institution and/or program as an SVS partner. We look forward to hearing from you, and to your engagement in this capacity building enterprise. The SCOSTEP SVS committee: M. Grande (chair), M. Hagan, N. Vilmer, A. Yoshikawa, B. Rabiu, J.-P.Raulin. Prof. Manuel Grande Aberystwyth University Penglais, Aberystwyth, Ceredigion, SY23 3BZ, Wales, UK. Phone: (44)1970 622624, Fax: (44)1970 622826, Mobile: (44) 7881 858945 Email M.Grande@aber.ac.uk Maura Hagan National Center for Atmospheric Research hagan@ucar.edu +1-303-497-1537 +-------------------------------------------------------------------+ | To broadcast announcements to the GEM community, please contact | | Peter Chi, GEM Communications Coordinator, at: | | | | | | Please submit your announcements in plain text or Word document. | | | | To subscribe the GEM Messenger, send an e-mail to | | | | with the following command in the body of your e-mail message: | | subscribe gem | | To remove yourself from the mailing list, the command is: | | unsubscribe gem | | | | GEM Messenger is also posted online via newsfeed at | | http://heliophysics.blogspot.com and | | http://www.facebook.com/heliophysics | | | | Back issues are available at: | | http://www-ssc.igpp.ucla.edu/gemwiki/messenger/ | | | | URL of GEM Home Page: http://aten.igpp.ucla.edu/gemwiki | | Workshop Information: http://www.cpe.vt.edu/gem/index.html | +-------------------------------------------------------------------+