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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. - PowerPoint PPT Presentation
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Improving Salammbô model and coupling it with IMPTAM model
V. Maget1
D. Boscher1, A. Sicard-Piet1, N. Ganushkina2
1. ONERA, Toulouse, FRANCE2. 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
• Plots of interest:• L* vs Time representation• Making a satellite fly in the model
• Origin:Sun (through plasmasheet)
• Effects: TiD, surface and deep charging
GEOGPS
POES15 >100keV
RB
SP-A 0.57-1.12 M
eV
• Earth’s radiation belts bases:• 3 quasi-periodic movements due to magnetic
field trapping
• Definition of an adequate coordinate systemL*, Aeq, MLT, Energy
• What a satellite really observes ?
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
Radial diffusion
w-p interactions
GPS
GEO
Optimizing the science bricks combination (1/3)
Omnidirectional fluxes @ eq for E = 1,5 MeV -- Kp=2
1,00E+00
1,00E+01
1,00E+02
1,00E+03
1,00E+04
1,00E+05
1,00E+06
1,00E+07
1,00E+08
1,00E+09
0 1 2 3 4 5 6 7 8 9
DLL = Brautigam -- BC = CRRES DLL = Brautigam -- BC = BOSCHERDLL = BOSCHER -- BC = BOSCHER
Omnidirectional fluxes @ eq for E = 1,5 MeV -- Kp=4
1,00E+00
1,00E+01
1,00E+02
1,00E+03
1,00E+04
1,00E+05
1,00E+06
1,00E+07
1,00E+08
1,00E+09
0 1 2 3 4 5 6 7 8 9
DLL = Brautigam -- BC = CRRES DLL = Brautigam -- BC = BOSCHERDLL = BOSCHER -- BC = BOSCHER
High activity1.5 MeV
Low activity1.5 MeV
Omnidirectional fluxes @ eq for E = 1,5 MeV -- Kp=2
1,00E+00
1,00E+01
1,00E+02
1,00E+03
1,00E+04
1,00E+05
1,00E+06
1,00E+07
1,00E+08
1,00E+09
0 1 2 3 4 5 6 7 8 9
DLL = Brautigam -- BC = CRRES DLL = Brautigam -- BC = BOSCHERDLL = BOSCHER -- BC = BOSCHER
• 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:
Flux
in M
eV-1 c
m-2 s
-1 s
r-1
L* L*
109
107
105
103
10
Optimizing the science bricks combination (2/3)
• Cold plasma densities influence wave – particle interaction:
1.00E+00
1.00E+01
1.00E+02
1.00E+03
1.00E+04
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
1.00E+11
1.00E+12
1.00E-02 1.00E-01 1.00E+00 1.00E+01
Flux
(cm
-2.s
-1.M
eV-1
)
Energy (MeV)
t=0 hr
t=6 hrs
t=12 hrs
t=18 hrs
t=24 hrs
10-2 10-1 100 101
Energy (MeV)
Flux
(cm
-2.s
-1.s
r-1)
100
102
104
106
108
1010
1012MLT=0h, L*=6.0, percentile 5%
1.00E+00
1.00E+01
1.00E+02
1.00E+03
1.00E+04
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1.00E+09
1.00E+10
1.00E+11
1.00E+12
1.00E-02 1.00E-01 1.00E+00 1.00E+01
Flux
(MeV
-1.c
m-2
.s-1
)
Energy(MeV)
t=0 hr
t=6 hrs
t=12 hrs
t=18 hrs
t= 24hrs
10-2 10-1 100 101
Energy (MeV)
Flux
(cm
-2.s
-1.s
r-1)
100
102
104
106
108
1010
1012MLT=0h, L*=6.0, percentile 95%
• 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
Low 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
RBSP-A 0.05-0.06 MeV
Salammbô 0.57-1.12 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 stormComparison with CRRES data
330 keV 1.17 MeV
CRRES
NO DROPOUTS
DROPOUTS
KP INDEX
Modelling magnetopause shadowing effect (3/4)• 16th – 30th September 2007 drop-outs
GOES 10
GOES 12
> 600 keV
> 2 MeV
> 600 keV
> 2 MeVObservation
Simulation without drop-outs modelling
Simulation with drop-outs modelling
Integrated flux in cm-2 s-1 sr-1
Color code
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
Kp index
50 – 75 keV
170 – 250 keV
Observation from LANL_97A
Salammbô alone
Salammbô + IMPTAM
Color code
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