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Improving Salammbô model and coupling it with IMPTAM model . V. Maget 1 D. Boscher 1 , A. Sicard-Piet 1 , N. Ganushkina 2 ONERA, Toulouse, FRANCE FMI, Helsinki, FINLAND. SPACECAST Final Outreach Meeting, BAS, Cambridge, 07 th February, 2014.
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Improving Salammbô model and couplingitwith IMPTAM model V. Maget1 D. Boscher1, A. Sicard-Piet1, N. Ganushkina2 ONERA, Toulouse, FRANCE FMI, Helsinki, FINLAND SPACECAST Final Outreach Meeting, BAS, Cambridge, 07th February, 2014
Bases to better understand Radiation belts modelling Particles of interest today: • Electrons: from keV up to a few MeV • Earth’s radiation belts bases: • 3 quasi-periodic movements due to magnetic field trapping • Definition of an adequate coordinate system L*, Aeq, MLT, Energy • What a satellite really observes ? • Effects: TiD, surface and deep charging • Origin: Sun (through plasmasheet) • Plots of interest: • L* vs Time representation • Making a satellite fly in the model GEO GPS POES15 >100keV RBSP-A 0.57-1.12 MeV
Purpose: the global optimization problem • The model is a complex balance between all active physical processes • Work done during the SPACECAST project: • Improving the most significant bricks of physics ahead of Salammbô model • Determining the best combination of them by comparing to real data (GEO, Van Allen Probes, …) • Poor physics below about 100 keV due to E-field influence: plug with IMPTAM model Boundary condition w-p interactions Radial diffusion GPS GEO
Optimizing the science bricks combination (1/3) • Improved bricks during the SPACECAST project: • Enhanced radial diffusion model based on data • Boundary conditions (THEMIS and NOAA-POES data statistical analysis) • Wave-particle interactions (primarily Chorus waves and plasma densities influence) • Drop-outs modelling (focus on in the following) • Influence of boundary conditions and radial diffusion modelling: 109 High activity 1.5 MeV Lowactivity 1.5 MeV 107 105 Flux in MeV-1 cm-2 s-1 sr-1 103 10 L* L*
Optimizing the science bricks combination (2/3) • Cold plasma densities influence wave – particle interaction: Lowdensity • Only few cold plasma models exist • The density shapes the interaction • Worst cases can be defined • Flux energy spectra may be very influenced by this density High density
Optimizing the science bricks combination (3/3) • Initial state and wave-particle interactions modelling influence: • From 27th February, 2013 to 28th March, 2013 • Two sets of wave-particle interactions (all type of waves) RBSP-A 0.57-1.12 MeV Salammbô 0.57-1.12 MeV RBSP-A 0.05-0.06 MeV Salammbô 0.05-0.06 MeV Kp index
Modelling magnetopause shadowing effect (1/4) • What is magnetopause shadowing effect?
Modelling magnetopause shadowing effect (2/4) • October 1990 magnetic storm Comparison with CRRES data 1.17 MeV 330 keV CRRES NO DROPOUTS DROPOUTS KP INDEX
Modelling magnetopause shadowing effect (3/4) • 16th – 30th September 2007 drop-outs Color code > 2 MeV Observation GOES 12 Simulation without drop-outs modelling Simulation with drop-outs modelling > 600 keV > 2 MeV GOES 10 > 600 keV Integrated flux in cm-2 s-1 sr-1
Modelling magnetopause shadowing effect (4/4) • Inclusion in the upcoming release
Improving low energy rendering: IMPTAM plug • Work in progress… • Salammbô 3D physics is poor below about 100 keV thus IMPTAM outputs are considered as always better ! • The coupling is based on a data assimilation pattern: each time IMPTAM outputs are available they are ingested in Salammbô • Encouraging first results 170 – 250 keV Color code 50 – 75 keV Observation from LANL_97A Salammbô alone Salammbô + IMPTAM Kp index
Conclusions • Conclusions • Bricks of physics have been improved (radial diffusion, boundary condition, wave-particle interaction) • Their combination improves SALAMMBO precision (factor of 2 to 10) • Still a challenge to select the perfect combination valid for any magnetosphere configurations (depend on energies, magnetic activities, initialisation, plasma densities …) • Drop-outs modeled in Salammbô model: improve the results (will be included in the upcoming release) • IMPTAM model improves SALAMMBO outputs below 100 keV • Each step made has been compared to in-flight measurements
Acknowledgements • The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no 262468, and is also supported in part by the UK Natural Environment Research Council