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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

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