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1 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Summary of THEMIS results in the inner magnetosphere Future mission operations discussion: –Science targets.

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Presentation on theme: "1 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Summary of THEMIS results in the inner magnetosphere Future mission operations discussion: –Science targets."— Presentation transcript:

1 1 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Summary of THEMIS results in the inner magnetosphere Future mission operations discussion: –Science targets –What do we need to change (if anything)? THEMIS in the inner magnetosphere: Review of current

2 2 THEMIS Inner Magnetosphere Review, Dec 20, 2008 THEMIS Extension (FY10,11,12)

3 3 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Extended THEMIS Baseline (P3,P4,P5) At Inner Magnetosphere, Study Role of: –ULF/VLF/EMIC waves on ion, electron energization/losses –Large electric fields on storm time ring current Result: –Comprehensive AC waves and E-fields models Using novel: –0.1-2R E separations to resolve temporal/spatial evolution of gradients –daily conjunctions: PFISR, S-DARN P3 P4 P5

4 4 THEMIS Inner Magnetosphere Review, Dec 20, 2008 EMIC waves Usanova et al., GRL, 2008 1 2 3 - Driven by SW P dyn - Confined to L=5-6.5 - Structured, with good ground-space correlation - Potentially important for RB loss.

5 5 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Ring Current Ions Electrons Dst storm index TH-B TH-D TH-B TH-D TH-B - Ions penetrate deep into the inner magnetosphere, and remain after storm. - Electrons also come close to Earth, but decay fast after storm recovery. Wang et al., GRL, 2008

6 6 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Angelopoulos et al., First Results from THEMIS, Space Sci. Reviews, 2008 V ~ 350km/s Speed: 1MLT/min Substorm Injection Westward Propagation 97A 046

7 7 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Injection Simulated as localized pulse Liu, Wenlon et al., JGR, 2008

8 8 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Electrons, TH-A Ions, TH-C, B, E Plasma Sheet Injections Runov et al., GRL, 2008 -Nose structure, temporal -Electron injection local, transient

9 9 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Generation of whistler emissions Li et al., JGR, 2008 Low and upper band chorus emissions correlate with 5-10keV electron anisotropy –10keV electrons at higher L-shells have sufficient anisotropy to generate observed wave power –1keV electrons can penetrate deep but don’t have the required anisotropy to generate chorus –Higher plasma density results in higher amplitudes

10 10 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Whistler emissions Cully et al., GRL, 2008 Localized, large amplitude chorus emissions –Bursts of sub-second duration –Greater than100mV/m –L~3.5-5.5; dMLT = 1-3 hrs Mean/average not good description of wave field

11 11 THEMIS Inner Magnetosphere Review, Dec 20, 2008 KH wave seen by THC,B,D,A –Couples to ULF wave on TH-E Driven ULF wave is localized –Phase change 180 o at peak amplitude KH-wave driven FLRs: Agapitov et al., JGR, 2008

12 12 THEMIS Inner Magnetosphere Review, Dec 20, 2008 FLR Polarisation as Data – Electric Field Data – Magnetic Field 0 -8 -6 -4 -2 0 -10 -8 -6 -4 -2 Model – Electric Field - m1 (poloidal) Model – Magnetic Field - m1 Model – Electric Field - m2 (toroidal) Model – Magnetic Field - m2 Polarisation of Pc5 ULF changes along THEMIS orbit. Agreement with twisted eigenmode solutions (Rankin et al., Kabin et al.) Importance of FLR in structure? [Sarris et al., 2008]

13 13 THEMIS Inner Magnetosphere Review, Dec 20, 2008 FLR Statistics Occurrence rates. Pc4 Pc5 Poloidal Toroidal Pc4 Pc5 Poloidal Toroidal [Liu et al., 2008] Wave Power. Wave power shows absence of storm time afternoon side Pc4-5 power.

14 14 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Summary THEMIS already presents significant present capability to measure: –Waves, particles and their interactions from the radiation belts out to the plasma sheet Continuous operations from solar min to solar max Can provide plasma sheet sources, measure ULF, EMIC waves for studying radiation belt dynamics Can provide rapid crosses of radiation belt electron phase space density Multiple satellites can provide information on phase and group velocity String of pearls configuration can resolve spatio-temporal ambiguities Critical importance will be storms in continuing and extended mission

15 15 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Instrument overview Probe instruments: ESA: ElectroStatic Analyzer (coIs: Carlson and McFadden) SST: Solid State Telescopes (coI: Larson) FGM: FluxGate Magnetometer (coIs: Glassmeier, Auster & Baumjohann) SCM: SearchCoil Magnetometer (coI: Roux) EFI: Electric Field Instrument (coI: Bonnell) SST ESA EFIa EFIs FGM SCM T spin =3s

16 16 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Extended THEMIS Baseline (P3,P4,P5) At the Magnetotail, Study: –Nature of the near-Earth current sheet –Dissipation of bursty fast flows Result: –Ability to map and model key instability region 2010-04-10 00:00:00 P3 P4 P5 X Z X Y With first ever: –Simultaneous dR-dZ separations, 0.1-1R E –Clustered orbits study the 8-12R E region FAST

17 17 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Extended THEMIS Baseline (P3,P4,P5) At Subsolar Magnetopause, study: –Asymmetric reconnection: dynamics, evolution and role of cold ions –Internal FTE structure and electron acceleration Result: –Hall-physics of subsolar magneto-pause reconnection, paves way to MMS 2010-04-10 00:00:00 P3 P4 P5 X Z [THEMIS Coast Phase Mozer et al. GRL] Using novel: –Simultaneous dR-dZ separations at 0.1-0.5R E monitor inflow and outflow –Cluster-like separations at subsolar region

18 18 THEMIS Inner Magnetosphere Review, Dec 20, 2008 Data availability


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