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

260404 Astroparticle Physics 2

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 %

260404 Astroparticle Physics 3

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?

260404 Astroparticle Physics 4

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

260404 Astroparticle Physics 5

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

260404 Astroparticle Physics 6

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?

260404 Astroparticle Physics 7

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.

260404 Astroparticle Physics 8

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

260404 Astroparticle Physics 9

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

260404 Astroparticle Physics 10

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

260404 Astroparticle Physics 11

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

260404 Astroparticle Physics 12

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

260404 Astroparticle Physics 13

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Cronin 2004Cronin 2004

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

Conflicting observ.Conflicting observ.Inconclusive statisticsInconclusive statistics

260404 Astroparticle Physics 15

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

260404 Astroparticle Physics 16

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

260404 Astroparticle Physics 18

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

260404 Astroparticle Physics 19

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