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WG2 Summary Broke into ring current/plasmasphere and radiation-belt subgroups RING CURRENT Identified events for addressing science questions
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WG2 Summary • Broke into ring current/plasmasphere and radiation-belt subgroups • RING CURRENT • Identified events for addressing science questions • What is the relative importance of the convection electric, penetration electric field, and variations of the plasma sheet distributions to the ring current? • #45 21 Oct. 2001 Polar EFI data shows dipolarizations at 9 RE, 22 MLT that are correlated with time derivative of Dst (ring current injections), earthward Poynting flux and energization of O+ (more than protons) observed by Polar/MICS. IMAGE/HENA observes the O+ injection as it reaches the ring current region (~100 keV) and precipitates on the upper atmosphere. Polar MPE, LANL/MPA & SOPA data avail. • Modeling – Chen,Jordanova, Liemohn
The ring current causes large negative magnetic field perturbations as well as enhancements in fluxes of ions with 1-200 keV in the inner magnetosphere yet these features have not been simultaneously accounted for from in-situ particle & field and ENA observations. To what extent are these observations consistent with each other and with models within our current framework of understanding of the ring current based on transport and loss? • #28-29 11-12 Aug 2000 Polar CAMMICE shows enhancements of H+ fluxes during storm main phase. IMAGE/HENA fluxes, Polar/MFE, LANL/MPA and SOPA avail. • Modeling – Chen, Liemohn
PLASMASPHERE- Plan for Interchange Investigation Goal: Determine the what role (if any) interchange, ballooning, and/or Kelvin-Helmholtz instability might play in the global evolution of the plasmasphere, especially during erosion, formation of plumes, etc., but also during quiet times. Method: Use in situ data to make concrete predictions for observable features of instabilities in plasma. Try to observe these features in EUV data. Data: Ionospheric dataDMSP In situ equatorial (or near equatorial) data Cluster CODIF remote sensing equatorial IMAGE EUV Plan: 1. Identify conjunctions of Cluster in inner magnetosphere (and CODIF measuring in RPA mode) and IMAGE EUV. 2. identify events that have good erosion in EUV. If good data in CODIF, proceed to step 4. 3. If no good events in both CODIF and EUV, broaden search to look at non erosion times. 4. Get DMSP data for input to calculations of Richardson number and predict, a. growth rate of instability b.scale size, speed (and other parameters) of observable features With predictions for observable features of plasma, look at EUV data.
RADIATION BELT Over what solar wind conditions and L range is radial transport vs. localized acceleration of electrons dominant? Empirical models have been successful at predicting geosynchronous fluxes based exclusively on input solar wind parameters, assuming radial transport as the dominant energization mechanism and parameterized L, energy-dependent loss. ULF and VLF wave power vs. L, correlated with electron phase space density and solar wind conditions and timing, needs further correlative, superposed epoch and event study. How does the ring current affect the radiation belt? WG1 & WG4 overlap #48 24 Nov 2001 Check for overlap of ring current & #50-51 18-20 Apr 2002 plasmasphere from HENA data & high- energy e- precipitation Study de-trapping of solar energetic protons due to ring current during (#70) 20 Nov. 2003 storm (S. Young’s model)
WG2 Focused Event List: #27 16 July 2000 Good CAMMICE in im; sq # 5, WG3 overlap ULF wave data, good LANL coverage,IMAGE #28-29 11-12 Aug 2000 Good CAMMICE in im, CEASE, HENA; no SEP, enhancement of energetic el, sq #6 #33 29 Oct 2000 Good Polar/CAMMICE, HENA, EUV, sq #6 # 37 31 Mar 2001 Superstorm weak RB, strong RC, WG3 overlap #45 21-23 Oct 2001 ENA, good Polar EFI #47 6 Nov 2001 CLUSTER in p.s., SEP trapping, rb model results # 48 24 Nov 2001 SEP trapping, rb and ring current model results #50-51 18-20 Apr 2002 Good CAMMICE in p.s., EUV, HENA, CLUSTER in i.m. in rec. phase; sq #5, WG3 #58-60 1 Oct 2002 Good CEASE, HENA, CLUSTER in i.m. in rec. phase; no SEP, enhancement of energetic el #68-69 30 Oct 2003 Good CEASE, EUV; SEP, CLUSTER in recovery phase; Superstorm, sq # 5 WG3 overlap #70 20 Nov 2003 Good EUV, CLUSTER in ps; largest |Dst|, abrupt deep loss of energetic e-, sq # 5, WG3 #74-76 27 July 2004 Good CEASE, CLUSTER in ps; no SEP,G/HEO e- hi #78-79 08 Nov 2004 Good CEASE, EUV, G/HEO e- hi
Collectively agreed upon a table of key geomagnetic data: Maximum solar wind density & speed Shock arrival time IMF Bz, Btot Time and value of peak Dst, Kp, PCI and sum Kp over main phase Standoff distance to magnetopause Start & duration of main phase and storm Peak AMIE Cross Polar Cap Potential Min L, L and value of Max Counts/Flux of 2-MeV e- enhancement Peak radiation belt content indices Time-resolved electron dropouts at L~ 5 Electron Loss Index ULF Wave Activity Location of plasmapause (day, min. & average L of plasmapause) Presence of Plume (Yes/No) EUV witness erosion (No/Yes & time) Average of LANL/MPA density and temperature during PM main and recovery phases Normalized integrated HENA flux Inner edge of ring current from HENA Sawtooth Oscillations (Yes/No)