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Interplanetary magnetic field and relativistic solar particle events. S. Masson 1 , S. Dasso 2 , P. Démoulin 1 and K.-L. Klein 1. 1 LESIA - Observatoire de Paris 2 IAFE - Universitad de Buenos Aires. Interplanetary magnetic field and relativistic solar particle events - PowerPoint PPT Presentation
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Interplanetary magnetic field
and relativistic solar
particle eventsS. Masson1,
S. Dasso2, P. Démoulin1 and K.-L. Klein1
1 LESIA - Observatoire de Paris
2 IAFE - Universitad de Buenos Aires
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
How can we constrain acceleration of relativistic protons ?
Synchrotron emission: relativistic e-.
Relativistic protons
X-rays and -rays: Impact
Beams of non-thermal electrons : radio emission
Earth
Shock waves: radio emission
From Earth measurements, go back to Sun across the Parker spiral (1.2 AU)
Constrain the acceleration regions of relativistic particles
Multi wavelengths analysis
Parker spiral
GLE measurements
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
The timing and connection problem
Carmichael (1972), Kodama et al. (1977), Cliver et al. (1982), Kahler et al. (2003)
Delay between the arrival time of the first relativistic protons at the Earth (=ground level enhancement or GLE) and various electromagnetic signatures of particle acceleration.
Active regions associated to GLEs not always Earth-connected by the Parker spiral.
Cliver et al. (1982), Stoker (1994), Gopalswamy (2005)
ww
w.nm
db.eu
Why is there a systematic delay, and what determines the magnetic connection ?
Parker spiral connection
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August 2010
- Acceleration by the CME’s shock high in the corona
- Delayed acceleration of energetic particles during the flare
- Particle diffusion during the interplanetary transportWibberenz & Cane (2006), Cane (2003), Richardson et al. (1991)
Klein et al. (1999), Li et al. (2009)
Kahler (1994), Cliver et al (2004), Reames (2009)
Should we always consider the Parker spiral as the real connection between the acceleration site and Earth ?
The timing and connection problem
How to explain the delay and the connection problem
based on the propagation of particles along the Parker spiral
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
GLE on 20 January 2005
Masson et al. (2009)
Detailed temporal analysis
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
Most energetic protons > 300 MeV and electrons are accelerated during the second episode 06:45:30 UT
A longer interplanetary path length
€
d =1.4 AU Injection time at 06:46 UT
Common release of radio emitting electron beams and relativistic protons
Measurements of the magnetic field and plasma parameters
The interplanetary magnetic field (IMF)
Sun-Earth connections and IP path length
Interplanetary coronal mass ejection or magnetic cloud
D > 1.2 UA
Parker spiralD ~ 1.2 AU
EarthEarth
Interplanetary magneticfield lines
particlesemission
Which IMF for particle propagation ?
Magnetic structure of the IP space
In-situ particles measurements(Velocity dispersion analysis)
Length travelled by energetic particles
Injection time of energetic particles
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
Magnetic structure of IMF during GLE
B ~ 6 nT
~ - 45°
~ 0°
Texp
Tobs
p ~ 1
Propagation along the Parker spiralin a quiescent solar wind
GLE
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
Parker spiral (quiet IMF)
- B non coherent, Bmag ~ 5 nT
-T exp ~ Tobs~ 2.105 K
- p ~ 1
(Lopez & Freeman, 1986; Elliot et al., 2005)
Magnetic structure of IMF during GLE
Propagation of particles in the back < 1
Back
ICME
GLE
Texp > 2 Tobs
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
Interplanetary coronal mass ejection
- Increase of Bmag , high coherent Bmag
- T exp > 2 Tobs
- p < 1
( Liu et al., 2005; Ebert et al., 2009)
discontinuity of B components: B partially reconnected with the SW
(Dasso et al., 2006, 2007)
Back of ICME or MC
For the last 10 GLEs of the 23rd solar cycle
(www.srl.utu.fi/erne_data/)
Relativistic protons (4 GeV)Neutron monitor
Energetic protons (12-40 MeV) SoHO/ERNE
(Moraal et al., 2009)
Interplanetary length and solar release time
Velocity dispersion analysis
€
tonset =L
Vp+ tSRT
Solar release time
Assuming that all particles are injected simultaneously: €
D =1.20 ± 0.07 AU
tSRT = 05 : 29UT ± 2.5min26 December 2001:
Performing on 7 events (missing data)
Interplanetary length
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
Interplanetary length versus magnetic structure
2006 December 13: Interplanetary structure like Parker spiral and a travelled length of 2 AU (bad determination ?? shock acceleration ???)
Consistent results between path length and
interplanetary magnetic structure (7 GLEs)
28 /10 /03: relativistic particles travel ~ 2 AU
(Miroshnichenko et al., 2005)
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
Solar release time versus electron type III injection
Protons are injected during electron injection
event
Timing comparison of the injection time of protons at the Sun
and
the interval during which electrons are injected and produce type III
burst (ttypeIII background + 3)
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
Conclusion
Results
From two independent studies: - magnetic structure of the IMF - velocity dispersion analysis (travelled length)
consistent results for interplanetary length and the injection time
Interplanetary geometry plays a crucial role in the timing problem.
An essential constraint to associate the solar phenomena to particles acceleration
What is new for the understanding of solar relativistic particles?
Interplanetary magnetic field and relativistic solar particle eventsS. Masson - 10th RHESSI Workshop - Annapolis - August
2010
What is the effects of the magnetic structure on the particle transport ?
Development of model to compute the MC / ICME lengths
Detailed analysis of some events, taking into account the IMF structure
(Kahler, Krucker & Szabo, 2010)