cosmic rays in the heliosphere ecrs2006 - xx european cosmic ray symposium mikhail panasyuk moscow...
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Cosmic Rays in the Heliosphere
ECRS2006 - XX European Cosmic Ray Symposium
Mikhail Panasyuk
Moscow State University
Cosmic Rays in the Heliosphere
• Galactic Cosmic Rays
• Anomalous Cosmic Rays
• Solar Cosmic Rays
We imply, that
...are the main players ...
are
Energy spectra of cosmic rays
(solar minimum)
Galactic cosmic rays (H)
lg E (eV/nucl)3 9 12
10
-10
0
lg I
1 MeVn
6
1 GeVn 1 TeVn1keV/n
NOT SCALEDAnomalous cosmic rays (O)
Energy spectra of cosmic rays
(solar maximum)
Galactic cosmic rays (H)
lg E (eV/nucl)3 9 12
10
-10
0
lg I
1 MeVn
6
1 GeVn 1 TeVn1keV/n
NOT SCALEDAnomalous cosmic rays (O)
Energy spectra of cosmic rays
(solar maximum)
Solar wind (H)
Solar energetic particles (H)
Galactic cosmic rays (H)
lg E (eV/nucl)3 9 12
10
-10
0
lg I
1 MeVn
6
1 GeVn 1 TeVn1keV/n
NOT SCALEDJust a tendency!
The basic problemsof cosmic radiation study:
Sources:
- Where do the particles come from ?
• Particle’s transport :
- How do they propogate through heliosphere medium ?
and• acceleration processes
- How and where they get accelerated?
Galactic & Anomalous Cosmic Rays
GCR chemical composition/spectra
* Galactic and extra- Galactic origin.
• Practically all elements.
• Fully ionized
* Omnidirectional•108 - 1021 eV.
* Solar cycle modulation (11 years) at low energies.
Cosmic ray composition
• GCR: 90% H, 9% He, 1% CNO…
Enrichment by secondaries:
Li,Be,B
• ACR: He, N, O, Ne, but few C, Mg, Si, Fe;
O/C5 ( whereas in GCR
O/C~1).
Li,Be,B
Propagation and temporal variations
Modulation of GCR(neutron monitors data)
Solar activity
- Scattering on magnetic irregularities - diffusion; - A diffusion coefficient is the product of particle speed with an increasing function of rigidity.
Equatorial region
Polar region
Propagation and temporal variations
Modulation of ACR
Modulation of GCR & ACRWeak modulation for GCR
Strong modulation for ACR
Charge-Sign Dependent Solar ModulationCharge-Sign Dependent Solar Modulation
C 5+ -6+
O+
Where is modulation region?
• The radial GCR intensity distributions indicates the changes at ~15-25 AE with much stronger modulation for solar max at outer heliosphere, it means that 11-year modulation are mainly occuring in the outer heliosphere between 15 AE and TS
(McDonald, et al, 2003)
Modulation of ACR
Results of analysis of ACR oxygen at
Cosmos,WIND, Pioneer 10,
Voyager 1 and Voyager 2 during 1972- 1999 give an
estimation of modulation boundary - Bm ) location near
~90AE . ( Zhuravlev, et al , 2004).
Modulation boundary
R,AE
Intensity
Min SA,A>0
Max SA
~90AE
Leaky-box model and modulation
λesc
E,MeV103102 104
Soutoul- Ptuskin “strong”model : λesc ~β3R2
including effects of galactic wind
Higher energies escape easily from Galaxy
Effects of distributed CR acceleration as they pass through the interstellar medium
Leaky-box model and modulation
Soutoul- Ptuskin “strong”model : λesc ~β3R2
including effects of galactic wind
There is an agreement with:
CRIS/ACE data Davis, et al, 2000
But..
Leaky-box model and modulationBut the“ordinary“ λesc (E) dependence at low energy with a LOCAL SOURCE of CR give the close results, exept Sc-Ti- V group.
Therefore we cannot exclude the existence of local source
Charge state of cosmic rays
1 10 100
8+
1+
Q
SW GCR
(oxygen)
SEP
Direct methods Geomagnetic cutoff
0.1
MeV/nucl
ACR
Partially ionized HZE ions in the cosmic rays
«Salyut - 6» data
a region where a completely stripped Fe nuclei would be forbidden.
Expected cutoff
LatitudeThe most possible explanation of these observationsthat there are partially ionized iron ions at energy of
~ 200 Mev/nucl.
Partially ionized HZE ions in the cosmic rays
Experiment The last publication
Astro (Salut 6,1981) (Blazh et al, 1986)Anuradha ( Spacelab 3) (Dutta et al, 1993)Kashtan (Cosmos, 1990) (Grigorov, et al 1991)LDEF (1984 – 1989) (Tylka, et al, 1995)
About sources
How to explain low charge state of low -energy GCR?
- Local sources? - A possible way...
Red Dwarfs (after Yu. Stozhkov)?
Charge state of ACR (He, O...)- 1+
Are there a sources of ACR nearby?
For Red Drafts it should be proposed an existence of abnormal chemical composition
The main statements of the Fisk, Kozlovski Ramaty theory
The anomalous cosmic ray component
•Penetration of ISM neutralsfrom the interstellar mediuminto the heliosphere;
The main statements of the Fisk, Kozlovski Ramaty theory
The anomalous cosmic ray component
Then…
Ionization of neutrals due to ultraviolet and charge-exchange with ions of the solar wind;
The main statements of the Fisk, Kozlovski Ramaty theory
The anomalous cosmic ray component
Then…
•Acceleration of ionized neutrals, ‘picked-up’ by the solar wind from ~4 keV/nucleon to >10 MeV/nucleon at the heliopause (termination shock);
The main statements of the Fisk, Kozlovski Ramaty theory
The anomalous cosmic ray component
And then they will undergo
modulation and propagation inside
the heliosphere
The anomalous cosmic ray source
Adams, J.H. and Leising, M.D., 1991.: Losses by charge exchange reactions of O (O+->On+)
nH = 0,1 /cm3, <Q> =1+,
ACR life- time limit and source region:
dmax ~ 0,2 pc, or dmax/v = 4,6 years -
Local ISM dust is source of ACR
ACR source(s)
Alternative (or complementary) approach:
Ionosphere plasma of “magnetic” planets enriched by O+ can be a source
for ACR
Ionosphere as a source of plasma in the Earth’s magnetotail
Н+,He+,O+
Magnetic substorms/storms reconnection
Particles acceleration and outflowin antisolar direction
Magnetic substorms/storms reconnection
Particles acceleration and outflowin antisolar direction
Magnetic substorms/storms reconnection
Particles acceleration and outflow
in antisolar direction
Magnetic reconnection
Thermal plasma in the planetary ionospheres
Jupiter Saturn Uranus Neptune
Sources Io, moon Ionosphere
Icy moons, SW
Ionosphere Ionosphere
Triton, moon
Composition H,Na,O,K,S,H2O,N
H,OH,H2,O,N
H,He N,H,He
Source strength
~3x1028
i/sec
1026 i/sec 1025 i/sec 3x1025
i/sec
Large amount of H, ions heavier than He, and ~ absence of 12C
Estimation of internal ion source strength
How strong should be an internal (heliospheric) source of ions to fill the
heliosphere’s volume during a time less than (say) half of solar cycle?
Estimation of internal ion source strength
Then reqiured strength for internal ion source:
S = nesc VH / T ~ 4x1019 c-1
which is much less than known Jupiter’s ionosphere source strength SJ~ 1028 c-1
Need to be involve in calculation:
acceleraton efficiency and escaping of particles from
magnetospheric tails of the planet into heliosphere
Internal ACR source
Galactic Cosmic rays
Jupiter’s magnetosphere, 0,1 A.U.
O+
Double acceleration of ACR: during reconnection process in the magnetospheres of the giant planets
plus acceleration at heliospheric TS
Consequences of the “Model of internal source”
1.Jovian ionosphere is a strongest strength source: SJ ~ 1028 ions/sec; plus Earth, Saturn, Uranus and Neptune ionosphere sources. They can supply O+( and some other ions) into heliosphere.
2. No composition problem: absence of 12C in a source. But where is S?3. Ions can be preaccelerated in the giant planet’s magnetospheres
sulfur ?
Reconnection is everywhere
In the magnetospheres At the Sun
Magnetic reconnection as a main force for solar flare particle
acceleration
Solar flare standard model
Particle Acceleration in Flares
• Acceleration by DC electric field in Reconnecting Current Layer
plus...
• Collapsing trap dynamics
• Stochastic dynamics (waves, shocks)
1.Magnetic reconnection as an injector
Scenario of acceleration process
Reconnection region
Chromosphere
Flares loops
- Magnetic field lines
move to the X-type neutral point
-The electric field is induced
and accelerates particles
After Somov & Bogachev
1.Magnetic reconnection as an injector
Betatron acceleration connected with collaps of magnetic loopswith simultaneous Fermi acceleration (stochastic acceleraton)
Scenario of acceleration process
2.Electron capture and collaps of magnetic trapping region
Reconnection region
Chromosphere
Flares loops
• The betatron effect significantly increases the efficiency of the first-order Fermi-type acceleration
• Collapsing traps with a residual length (without shock) accelerate protons and ions well
Somov, B.V. and Bogachev, S.A., Astronomy Letters, 29, 621, 2003
Scenario of acceleration process
Stochastic acceleration throughout the loop - Miller/Petrosian
Turbulent acceleration site
Reconnection acceleration site
Solar flare standard model
Theoreticians state that SM can explain:
• energy release;
• particle acceleration mechanism;
• flares loops formation;
• and HXE emission sources.
SEP acceleration mechanism should explain experimental data:
Acceleration of
• Electrons up to 0.5s 60-100MeV • Protons up to 1-10s 300MeV-GeV
SM gives
Acceleration of protons and electrons
Protons
Electrons
Bogachev, et al
Protons can be accelerated up to GeV, but electrons only up to several MeV
Dependent on the plasma parameters
Plasma temperature, keV
Esc
apin
g e
ner
gy,
MeV
An additional diagnostic tools for solar flare dynamics and SEP
acceleration mechanisms
Gamma-ray and neutron production in solar flares
Electrons: x- ray, gamma-ray bremstruhlung
Ions: exited nuclei– γ– lines 1-8 MeV nuclear reactions: neutrons – free escaping 2,22 MeV gamma (H-capture) π0 -decay γ- emissions E > 10 MeV
Corona
Chromosphere
• Simultaneous measurements of protons, electrons, γ – rays and neutrons can provide an important information about the nature of generation mechanism of SEP during solar flare
An example:Coronas –F data during October,28 SEE event
CORONAS-F data during Oct., 28, 2003 event
The first phase The second - delayed phase
Pion-decay production
Protons,neutrons ,electrons,andgamma - rays
γ-ray spectra during solar flaresspectra during solar flares
~ e
10-2 10-1 100 101 102
1E-5
1E-4
1E-3
0.01
0.1
1
10
100
1000
10000
E, MeV E, MeVE, MeV
t=153s (1)
Me
V -1 s
-1 c
m -2
10-2 10-1 100 101 102
t=186s (2)
10-2 10-1 100 101 102
t=218s (3)
0.01 0.1 1 10 100
1E-5
1E-4
1E-3
0.01
0.1
1
10
100
1000
10000
t=250 s (4)
0.01 0.1 1 10 100
t=283s (5)
0.01 0.1 1 10 100
t=331s (6)
0.01 0.1 1 10 100
1E-5
1E-4
1E-3
0.01
0.1
1
10
100
1000
10000
t=395s (6)
0.01 0.1 1 10 100
t=453 s (7)
0.01 0.1 1 10 100
t=550 s (9)
Appearance of “ a bump” in -spectrum as evidence for 2-stages acceleration process during solar flare: the most energetic particles are generated during the 2-nd, delayed phase
There is real evidence for solar electron fluxes generation up to energy 60 MeV with via the decay process.
Generaton of electrons via -decay
e decay process
Kuznetsov et al, 2006
Coronas – F data
Electron spectrum
Acceleration of SEP during propagation
Fermi acceleraion
Berezhko :ions up GeV!
N.Gopalswami:
If these SEPs are accelerated by CME-driven shocks, they use a significant fraction of the shock kinetic energy (~3% to 20%)
CME shock acceleration
SEP acceleration mechanisms
A: Electric Fields: Parallel to B Field Parallel to B Field
B: Fermi Acceleration
1. Shocks: First Order Fermi First Order Fermi
2. Stochastic Acceleration: Second Order Second Order FermiFermi
Shock’s acceleration is everywhere!
SW GCRN ~ 1cm-3 10-3 cm-3
B ~ 1nT 10-2 nT
T ion ~ 10 eV 103 eVMach ~ 5 100T ~ hours minutes
CME
SN
The main statements of the Fisk, Kozlovski Ramaty theory
The anomalous cosmic ray component
Then…
•Acceleration of ionized neutrals, ‘picked-up’ by the solar wind from ~4 keV/nucleon to >10 MeV/nucleon at the heliopause (termination shock);
The anomalous cosmic ray acceleration
FIRST ORDER FERMI OR COMPRESSIVE SHOCK ACCELERATION
Krymski (1977), Axford et al. (1977) and Blandford and Ostriker (1978):
The anomalous cosmic ray acceleration
1st order Fermi Shock drift
+irregularities
Acceleration efficiency increases toward the more perpendicular the geometry of shock and s – compression factor
Electric field E= -V/B
The anomalous cosmic ray acceleration
1st order Fermi Shock drift
+irregularities
Acceleration efficiency increases toward the more perpendicular the geometry of shock and s – compression factor
Electric field E= -V/B
But: there is pre-acceleration/injection problem which
remains one of the main research problems .Basically, for typical parameters the pick up ions must
be accelerated by a factor of 100 before the perpendicular shock becomes efficient
Internal ACR source
Galactic Cosmic rays
Jupiter’s magnetosphere, 0,1 a.e
O+
Internal ACR model:Acceleration of ACR during reconnection
process in the magnetospheres can provide preacceleration process
Consequences of the “Model of internal source”
Ions can be preaccelerated in the giant planet’s magnetospheres
No injection problem
Direct observation of ACR acceleration:
Voyager data
ACR spectra near an outer acceleration region
Expected ( from Fermi acceleration )
ACR before TS and inside the heliosphere
10 MeV/ nucleon
E
j
Modulation
ACR He Spectral EvolutionV1 crossed shock on 2004/351 between bottom two spectra on left
Expected source spectrum was not observed at time of shock crossing
V1 ACR He spectrum is unrolling in heliosheath as though V1 is closer to the source than V2, but note:
V1 now ~10 AU downstreamV2 now <5 AU upstream
Where is the ACR source?Near the ecliptic?Along the flanks? In the heliosheath?
Stone et al. Science 2005 Cummings & Stone COSPAR 2006
Let’s see...
Lisbon area
Future will show...
Prospects for the future
2000 2010 2020 2030
SDO
STEREO
SOHO
ACE
Cycle 24
Coronas FCoronas-Foton
SENTINELS
Interhelios
Heliospheric flotilia getting started...
Chineese & Japaneese
Thank you
Lisbon area