Belgian Institute for Space Aeronomy (BIRA-IASB)
Institut d’Aéronomie Spatiale de Belgique (IASB)
Belgisch Instituut voor Ruimte-Aeronomie (BIRA)
Space weather effects of the
solar wind on different
regions of the magnetosphere
BELGISCH INSTITUUT VOOR RUIMTE-AERONOMIE INSTITUT D’AERONOMIE SPATIALE DE BELGIQUE BELGIAN INSTITUTE OF SPACE AERONOMY BELGISCH INSTITUUT VOOR RUIMTE-AERONOMIE INSTITUT D’AERONOMIE SPATIALE DE BELGIQUE BELGIAN INSTITUTE OF SPACE AERONOMY BELGISCH INSTITUUT VOOR RUIMTE-AERONOMIE INSTITUT D’AERO
IAP
Charm
Viviane PIERRARD
Kinetic models based on the solution of the evolution equation
Solar wind
 
f  f  f
 
1   
 v    a        Af 
  Df   (WPI )[1]
t
r
v
v 
2 v

Friction
Diffusion
1. Vlasov (analytic)
2. Fokker-Planck
3. WPI kinetic Alfven waves
4. WPI Whistler turbulence
Pierrard et al., Sol. Phys., 2014
Pierrard et al., JGR, 2001
Pierrard & Voitenko, Sol. Phys.2013
Pierrard et al., Sol. Phys. 2011
Knudsen = mean free path/H
Exosphere: Kn>>1 Vlasov equation
Exobase: Kn=1
Solar wind escape: 1.1-5 Rs
Barosphere: Kn<<1 Fokker-Planck
Pierrard V., “Exploring the solar
wind”, 221-240, Intech, ISBN 978953-51-0339-4, 2012
Velocity distribution functions observed in situ in
the solar wind
Electrons 1 AU WIND
core
halo
Protons 0.5 AU Helios
strahl
B
Ions He O Ne 1 AU WIND
Kappa functions
 m 
fkappa 

3/ 2 
2k  2kT 
n
3/ 2

mve 

Ak 1 

2
kT
k


2
 (k 1)
Ulysses electron distributions fitted with
Kappa functions
Results:
<k> = 3.8 +/- 0.4 for v > 500 km/s (4878 observ.)
<k> = 4.5 +/- 0.6 for v < 500 km/s (11479 observ.)
Ions WIND:
k=2.5
General in space plasmas
Pierrard and Lazar, Sol. Phys., 287, 153174, 10.1007/s11207-010-9640-2, 2010
Solar wind
kinetic model:
profiles of the
moments
Kappa=2
Not classical heat flux
Maxwellian
Pierrard et al., Solar
Phys., 2014
Pierrard, Space Sci. Rev., 172, 315, 2012
Solar wind minor ions
Kappa=5 for all
species
T=10000 K at the
top of
chromosphere
Heating of the
corona by velocity
filtration
Acceleration of the
ions
Pierrard, Space Sci. Rev.,
172, 315, 2012
Solar wind model
SDO observations
29 May 2013 coronal holes
directed to the Earth.
ACE observations of velocity at 1 AU
Pierrard & Pieters, ASP,167-172, 2014
Model with collisions and whistler turbulence
Bottom (collision-dominated):
Electron velocity distribution function
f(2 Rs,m>0,v) = maxwellian
Top (collisionless conditions):
f(14 Rs,m<0,v<ve) = f(14 Rs,m>0,v<ve)
f(14 Rs,m<0,v>ve) = 0
Pierrard, Lazar & Schlickeiser, Sol. Phys. 287, 421, 2011
Storms and substorms
Geomagnetic activity indices (based on B at the surface of the Earth)
Kp [0-9]
Dst
AE
PC
1939
1964
1966
1991
13 stations
4 stations
12 stations N
1 station
(11N, 2S 44-60°)
(eq)
(aur)
(pol)
Corotating Interaction Regions
CR2075
u
B
CR2075
CR2076
Dst
Depends on u, B, q, n
Auroral regions
Current-voltage relationship
FUV IMAGE
Pierrard et al., J. Atmosph. Sol. Terr. Phys., 69 doi:
10.1016/j.jastp.2007.08.005, 2007
Terrestrial magnetosphere
Van Allen Radiation belts
Energetic protons and electrons
Electron flux in the 0.5-0.6 MeV
at 820 km measured by EPT on PROBA-V
Pierrard et al., Space Sci. Rev., doi:
10.1007/s11214-014-0097-8, 2014
Van Allen Radiation belts
internal: p+ (100 keV-500 MeV)
e- (10 keV-10 MeV)
4 Rt
AP8 Max J(E>10 MeV)
L (Re)
external: p+ (<10 MeV)
e- (10 keV-5 MeV)
10 Rt
AE8 Max J(E >1 MeV)
L (Re)
High flux variations
Benck et al., SWSC, 3, doi:
10.1051/SWSC/2013024 , 2013
Dynamic model of the radiation
belts
Dynamic model of the
electron radiation belts
based on CLUSTER/RAPID
observations (2001-2012)
www.spaceweather.eu
Pierrard & Borremans,
subm. SWSC, 2014
Links Plasmasphere/radiation belts
Plasmasphere: 1 eV
Pierrard and Benck, AIP, 1500,
216, 2012 (SAC-C)
Darrouzet et al., JGR, 118, 41764188, 2013 (Cluster)
Radiation belts: > 200 keV
Terrestrial
plasmasphere
and plasmapause
position
Web-based forecasting and
nowcasting model
on www.spaceweather.eu
http://ccmc.gsfc.nasa.gov
Ionosphere, GPS
9-6-2001/ 10-6-2001
Pierrard and Voiculescu, GRL 38, L12104, 2011
Comparison with
observations
Before
substorm
9 June
2001
8h00
After
substorm
10 June
2001
7h00
IMAGE (2000-2006):
RPI and
EUV He+ ions at 30.4 nm
Terrestrial polar wind
Input: n and T at 2000 km
+++ ewww p+
… O+
Pierrard and Borremans, ASP 459, 2012
Saturn and Jupiter
Pierrard V., Planet. Space Sci., doi :
10.1016/j.pss.2009.04.011, 2009
Electron density in the exosphere of
Jupiter
Auroral oval and footprints on Jupiter
Conclusions
- CMEs and solar wind high speed streams cause geomagnetic
storms and substorms
- Variations measured by geomagnetic activity indices (Kp, Dst)
- Auroral oval larger and wider
- High flux variations in the outer electron Van Allen belt
- High variability of the plasmapause position
- Comparison with the magnetosphere of other planets
- Kinetic models developed for space plasmas
- Models provided on www.spaceweather.eu
IASB-BIRA/STCE / IUAP CHARM
Conclusions
BELGISCH INSTITUUT VOOR RUIMTE-AERONOMIE INSTITUT D’AERONOMIE SPATIALE DE BELGIQUE BELGIAN INSTITUTE OF SPACE AERONOMY BELGISCH INSTITUUT VOOR RUIMTE-AERONOMIE INSTITUT D’AERONOMIE SPATIALE DE BELGIQUE BELGIAN INSTITUTE OF SPACE AERONOMY BELGISCH INSTITUUT VOOR RUIMTE-AERONOMIE INSTITUT D’AERO
• CMEs and solar wind high speed streams cause geomagnetic
substorms and storms
• Variations measured by geomagnetic activity indices at the ground
(Kp, Dst)
• Auroral oval larger and wider
• High flux variations in the outer electron Van Allen belt
• High variability of the plasmapause position
• Comparison with the magnetosphere of other planets
• Kinetic models developed for space plasmas
• Models provided on www.spaceweather.eu
IASB-BIRA/STCE / IUAP CHARM
The moments of f
Number density [m-3]
Particle flux
[m-2
s-1]
Bulk velocity [m s-1]
Pressure [Pa]


n( r ) 
 
F (r ) 

 

f ( r , v ) dv



   
f ( r , v ) v dv

 
 
F (r )
u (r ) 

n( r )

 
      
P(r )  m  f (r , v )(v  u )(v  u )dv

Temperature [K]
Energy flux [Jm-2 s-1]

T (r ) 

 
m
2 
f
(
r
,
v
)
v

u
dv
 
3k n(r ) 
  m   
 
2 
E ( r )   f ( r , v ) v  u (v  u ) d v
2 
Kappa distributions: theory and applications
in space plasmas
•
•
Generation of Kappa in space plasmas:
turbulence and long-range properties of particle interactions in a plasma
- plasma immersed in suprathermal radiation (Hasegawa et al., 1985)
- random walk with power law (Collier, 1993)
- turbulent thermodynamic equilibrium (Treumann, 1999)
- entropy generalization in nonextensive Tsallis statistics (Leubner, 2002)
- resonant interactions with whistler waves (Vocks and Mann, 2003)
• Dispersion properties and stability of
Kappa distributions
– Vlasov-Maxwell kinetics. Dielectric tensor
– The modified plasma dispersion function
– Isotropic /Anisotropic Kappa distributions
Pierrard and Lazar, Sol. Phys., 287, 153-174,
10.1007/s11207-010-9640-2, 2010
Consequence 3. Solar wind accelerated to high bulk
velocity due to the presence of suprathermal electrons
(Vlasov model)
k=2
Maxwell
Pierrard and Lemaire, JGR 101,
7923-7934, 1996
Pierrard, Space Sci. Rev., 172,
315-324, 2012
Te model
Consequence:
Non classical heat flux
Temperature inversion around 2 Rs
Te obs. polar
Te obs. equator
Qe model
Qp model
Classical heat flux
- Peak in electron temperature at 2 Rs
- Corresponds to coronal brightness measurements
obtained during solar eclipses
Heat flux
- not given by the Spitzer-Harm expression
- Spitzer-Harm heat flux assumed in fluid models
- No need of additional heating source to heat the
corona or to accelerate the wind
Pierrard V., K. Borremans, K. Stegen and J. Lemaire,
Solar Phys., doi: 10.1007/S11207-013-0320-x, 2014
Introduction
Solar wind
Kinetic models
Magnetosphere
Geomagnetic activity indices
Aurora
Van Allen belts
Plasmasphere-ionosphere
Conclusions