Astroparticle Physics Key Issues

260404 Astroparticle Physics 1

Astroparticle PhysicsAstroparticle PhysicsKey IssuesKey Issues

Jan KuijpersJan Kuijpers

Dep. of Astrophysics/ HEFINDep. of Astrophysics/ HEFINUniversity of NijmegenUniversity of Nijmegen


Cosmic Ray Energy SpectrumCosmic Ray Energy Spectrum

LHCLHC ||

_10_10-1-1

FluxFlux (m(m22 sr s GeV) sr s GeV)-1-1

_10_10-25-25

| || |101099 Energy (eV) 10 Energy (eV) 102020

SwordySwordy

Ankle (1 per kmAnkle (1 per km22-year)__-year)__

Knee Knee __(1 per m__(1 per m22-year)-year)

__(1 per m__(1 per m22-sec)-sec)

EE-2.7-2.7 E E-3-3

Flux x EFlux x E2.752.75

| | | | 1 Energy (GeV/n) 101 Energy (GeV/n) 1077

ee-- up to 1 TeV, only 1 % up to 1 TeV, only 1 %


Cosmic RaysCosmic RaysDirect detection:Direct detection:• Nuclei, power-lawNuclei, power-law• Gamma-rays up to TeV (AGN, pulsars)Gamma-rays up to TeV (AGN, pulsars)• Neutrinos Neutrinos (solar, SN1987a)(solar, SN1987a)Indirect detection from radiation: optically thinIndirect detection from radiation: optically thin synchrotron, inverse Compton, bremsstrahlung:synchrotron, inverse Compton, bremsstrahlung:• Electrons: power-law –2/–2.7/-3 over many decades in Electrons: power-law –2/–2.7/-3 over many decades in

extragalactic radio galaxies. Also in extragal. extragalactic radio galaxies. Also in extragal. GRBsGRBs, galactic , galactic SNRs, X-ray binaries, jets.SNRs, X-ray binaries, jets.

• Protons (X-ray and MeV galactic)Protons (X-ray and MeV galactic)

Main question: Main question: 1: UNIVERSAL ACCELERATION PROCESS?1: UNIVERSAL ACCELERATION PROCESS?


Particle acceleration processesParticle acceleration processes• Shock waves (Bell,..1977; Fermi 1954):Shock waves (Bell,..1977; Fermi 1954):

22 11

uu22 uu11

2

22 2

st

1 2

NR shock 21 order Fermi v

c cc

c

v v v"c c

vc c

2 1

1 2

1

22

acc

esc

u uu u

N(E ) E

E E

De Hoffmann-De Hoffmann-Teller frameTeller frame

SNRs: SNRs: vvss~few ~few 101044 km/s GRBs: km/s GRBs: ~300~300

Jets: Radio galaxies X-ray binariesJets: Radio galaxies X-ray binaries


10109 9 G_G_

BB

1010-9-9 G_ G_ 1 AU 1 pc 1 kpc 1 Mpc1 AU 1 pc 1 kpc 1 Mpc | | | || | | |Size (km) 10 10Size (km) 10 10

EEmaxmax==

ZeBLZeBL

Flare stars

MagnetarsPulsars

Stellar mass black holes

Massive black holes


More questions:More questions:

2

2

sync

radio optical X ray L

IC

e B ( f )

e

0

( ) ( )

e

... ...p / n N

/ K ... ... e

2: TeV gamma rays from electrons or protons?2: TeV gamma rays from electrons or protons?


Van den AkkerVan den Akker2004 PhD Thesis 2004 PhD Thesis KUNKUN

Case study: L3+Cosmics: search for TeV photonsCase study: L3+Cosmics: search for TeV photons

from GRBsfrom GRBs

from 64 EGRETfrom 64 EGRETunidentifiedunidentified30 MeV/30 GeV30 MeV/30 GeVGRSsGRSs

GRB 990903GRB 990903

Significance of muon excess

# muons per square degree per sec

not corrected for detector accept.

galacticcoordin.


Linear acceleration of primary electrons in Linear acceleration of primary electrons in unipolar inductor (neutron stars, unipolar inductor (neutron stars, accretion discs, black hole collapse + accretion discs, black hole collapse + torus) and subsequent pair creation in torus) and subsequent pair creation in strong B or photon background.strong B or photon background.

V v B d

Pair plasma productionPair plasma productionin circuit Cin circuit C

3: Origin 3: Origin ee plasma? plasma?

CC

CCRotationRotationaxisaxis


Fung & Kuijpers,Fung & Kuijpers,2004, A&A subm.2004, A&A subm.

Case study: Coherent emission from particle beamsCase study: Coherent emission from particle beams

Radio pulsars asRadio pulsars asFree Electron Free Electron LasersLasers

10001000

950 950t (10t (10-5-5 sec) sec)

E (V/m)E (V/m)

f (10f (10-10-10 Hz) Hz)

t (10t (10-5-5 sec) sec)

P (10P (101313 W) W)

varyingvaryingmagneticmagneticwigglerwiggler


DynamoDynamo

22

2 2

2nd

2

1 2

42 order Fermi

c cc

c

v v v"c c

vc

accretion disk compact objectaccretion disk compact object

Poynting flux dominatedPoynting flux dominatedMagnetized windMagnetized windJetsJets

5: Origin energy fireball?5: Origin energy fireball?

4: Origin of magnetic field?4: Origin of magnetic field?

- - Magnetic reconnectionMagnetic reconnection- Plasma turbulence Plasma turbulence - Stochastic accelerationStochastic acceleration


Case study: Coupling gravitational waves – mhd wavesCase study: Coupling gravitational waves – mhd waves

Magnetosonic waveMagnetosonic wave Alfven waveAlfven waveSSFFGG

AAGG

GWGW++ GWGWxx

Moortgat & Kuijpers 2003 A&A 402, 905 ; 2004 Phys Rev D, subm.Moortgat & Kuijpers 2003 A&A 402, 905 ; 2004 Phys Rev D, subm.

zz

xy


Cronin 2004Cronin 2004

Photopion productionPhotopion production

Photopair productionPhotopair production

6. Is there a high energy CR cut-off?6. Is there a high energy CR cut-off?

||GZK cutoffGZK cutoff



Cronin 2004Cronin 2004

7. Origin of highest energy CRs?7. Origin of highest energy CRs?

Conflicting observ.Conflicting observ.Inconclusive statisticsInconclusive statistics


Wilkens, 2003, Wilkens, 2003, PhD Thesis KUNPhD Thesis KUN

Case study: L3+Cosmics: composition – forward cross-sectionCase study: L3+Cosmics: composition – forward cross-section

muonsmuons

muon mul;tiplicityComparison to Monte Carlo CORSIKAComparison to Monte Carlo CORSIKA


Case study: L3+Cosmics: muon spectrum at sea levelCase study: L3+Cosmics: muon spectrum at sea level

Petersen, 2002Petersen, 2002PhD Thesis, KUNPhD Thesis, KUN

Charge ratioCharge ratio

Accurate absolute Accurate absolute spectrumspectrum

260404 Astroparticle Physics 17Cronin 2004Cronin 2004

Gamma ray: -----Gamma ray: -----Fe: _______Fe: _______Protons: Protons: ____________

Air showersAir showers

LOFAR cornerstone:LOFAR cornerstone:study of CRs and their sourcesstudy of CRs and their sources


High schools & High schools & cosmic rays:cosmic rays:detector construction,detector construction,observations,observations,analysisanalysis

Outreach opportunities: NAHSA – HiSPARC Outreach opportunities: NAHSA – HiSPARC - LOFAR- LOFAR

Timmermans et al,Timmermans et al,2004, KUN2004, KUN


Key questions in astroparticle physics:Key questions in astroparticle physics:

• ORIGINS CRs (HADRONS+LEPTONS): ORIGINS CRs (HADRONS+LEPTONS): SNRs, BHs, NSs, DARK MATTER, DARK ENERGYSNRs, BHs, NSs, DARK MATTER, DARK ENERGY• UNIVERSAL ACCELERATION PROCESS? UNIVERSAL ACCELERATION PROCESS? • TeV GAMMA RAYS FROM ELECTRONS OR PROTONS?TeV GAMMA RAYS FROM ELECTRONS OR PROTONS?• ORIGIN ORIGIN ee PLASMA? PLASMA? • ORIGIN OF MAGNETIC FIELD? ORIGIN OF MAGNETIC FIELD? • ENERGY PARTITIONINGENERGY PARTITIONING• IS THERE A HIGH ENERGY CR CUT-OFF?IS THERE A HIGH ENERGY CR CUT-OFF?• QUEST FOR HIGHEST ENERGY CRs AND SOURCESQUEST FOR HIGHEST ENERGY CRs AND SOURCES

2 communities astroparticle detectors2 communities astroparticle detectorsLOFAR + ANTARESLOFAR + ANTARES

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Astroparticle Physics Key Issues