ultra high energy cosmic rays -- observational results --

Ultra High Energy Cosmic Rays-- observational results --

M.Teshima

Max-Planck-Institut für Physik, München

Erice Summer SchoolJuly. 2004

Victor Hess 1912

Discovery of Cosmic Rays

John Linsley at Volcano Ranch (~1960)First discovery of super-GZK events

Cosmic Ray Energy Spectrum

P

γ3K

ΔＮ　

π

GZK mechanism

AGASA Energy Spectrum

Super GZK part.~1/km2 century

Background Radiations

in the universePair creation

GZK

Cosmic Rays and Neutrino

Candidates for EHE C.R. accelerator

Pulsar SNR A.G.N.

GRB

Radio Galaxy Lobe

Synchrotron radiation

GZK limit

Hidden HILLAS PLOT IIAnn. Rev. Astron. Astrophys. 1984, 22; p425-444

Cosmic Ray Propagation in our Galaxy

Deflection angle ~ 1 degree at 1020eVAstronomy by hadronic particles?

Cosmic Ray Propagation inGalactic Disk and Inter Gal.

Exposure in ICRC2003

Air Shower Phenomena

AGASAAkeno Giant Air Shower

Array

111 Electron Det.27 Muon Det.

0 4km

HiRes ExperimentAir Fluorescence detector

HiRes ExperimentAir Fluorescence technique

Measure Shower Development in the atmosphereEssentially Carolimetric measurement

Detector Calibration in AGASA experiment

Detector Gain by muons in each run

Cable delay (optic fiber cable)

Gain as a function of time(11years data)

Accuracy of 100ps by measuring the round trip time in each run

Detector Position

Survey from AirplaneΔＸ， ΔＹ＝ 0.1m, ΔＺ＝ 0.3m

Linearity as a function of time(11years data)

Detector Simulation (GEANT)

Detector Housing (Fe 0.4mm)Detector Box (Fe 1.6mm)Scintillator (50mm)Earth (Backscattering)

vertical θ = 60deg

Detector Response

Energy spectra of shower particles

Energy　 DeterminationLocal density at 600mGood energy estimator by M.Hillas

E=2.13x1020eV, E >= 1.6x1020eV

Third Highest event97/03/30 150EeV

40 detecters were hit

The Highest Energy Event (~2.46 x1020eV) on 10 May 2001

Attenuation curve S(600) vs Nch

1018eV Proton

Atmospheric depth

S600 Attenuation curve

　 0-45°

　 0-60°

Atmospheric depth

20.0

19.5

19.0

18.5

18.0

The Conversion from S600 to Energy

Muon/Neutrino

Ele. Mag

S600 Intrinsic fluctuation for

proton and iron

Proton

Iron

Major Systematics in AGASAastro-ph/0209422

Detector Detector Absolute gain ± 0.7% Detector Linearity ± 7% Detector response(box, housing) ± 5%

Energy Estimator S(600) Interaction model, P/Fe, Height ±15%

Air shower phenomenology Lateral distribution function ± 7% S(600) attenuation ± 5% Shower front structure ± 5% Delayed particle(neutron) ± 5%

Total ± 18%

Energy Resolution

30% 25%

mainly due to measurement errors (particle density measurement and core location determination)not due to shower fluctuation

Energy Spectrum by AGASA (θ<45)

11 obs. / 1.8 exp. 4.2σ

5.1 x 1016 m2 s sr

The Energy spectrum by AGASA Red: well inside the array

(Cut the event near the boundary of array)

Akeno 1km2 and AGASA

HiRes NSF events200-300EeV

HiRes I, II mono spectrum

AGASA vs HiRes (astro-ph)

Recent spectra (AGASA vs. HiRes@Tsukuba ICRC)

~2.5 sigma discrepancy between AGASA & HiRes

Energy scale difference by 25% vs. HiRes-stereo

vs. HiRes-I

vs. HiRes-II

World Energy Spectrum by M.Nagano 2002

Stecker 2003

by Douglas Bergman

20% energy variation

AGASA vs HiRes

AGASA HiRes

GZK-HypothesisExtended spectrumSuper-GZK

~2.4 σ

~4.2σ

~ 0 σ~ 0σ

~2.3 σ

Statistics

40% uncertainty

Impact parameter

Air Fluorescence yieldMeasurement

1. Bunner2. Kakimoto et al3. Nagano et al

Rayleigh Scattering

∝λ‐4

Possible Systematics in HiResMost of them are energy dependent

Air Fluorescence yield Total yield is known with 10~20% accuracy Yields of individual lines are not known well

Rayleigh Scattering effect ( 1/λ∝ 4)

Light transmission in air Mie Scattering

Horizontal attenuation, Scale Height, Wind velocity, Temperature single model represents whole data

Horizontal 12km (1999) 25km (2001)

Cherenkov light subtractionBias by Narrow FOV in elevation angleErrors in Mono analysis

Aperture estimation (Narrow F.O.V.) Chemical composition / Interaction dependent

Arrival Direction Distribution >4x1019eVzenith angle <50deg.

Isotropic in large scale Extra-GalacticBut, Clusters in small scale (Δθ<2.5deg) 1triplet and 6 doublets (2.0 doublets are expected from random) One doublet triplet(>3.9x1019eV) and a new doublet(<2.6deg)

Space Angle Distribution of Arbitrary two events >4x1019eV

Arrival Direction Distribution >1019eV

Space Angle Distribution

Log E>19.6Log E>19.4

Log E>19.2Log E>19.0

Energy spectrum of Cluster events∝E -1.8+-0.3

Cluster Component

Density of sourcesby Kachelriess and Semikos 2004

2D-Correlation Map in (ΔlII ,ΔbII )Log E >19.0eV, 3. 4σ Log E >19.2eV, 3. 0σ

Log E >19.4eV, 2.0σ Log E >19.6eV, 4.4σΔΔllIIII

ΔΔbbIIII

Cosmic Ray propagation in Galactic Magnetic Field

By Stanev

ΔｂII

ΔｌII

Aperture

Correlation with BL Lacsby Gorbnov et al. 2004

Full sky map of deflection angles

By K.Dolag, D.Grasso, V.Springel, and I.Tkachev

Expected Auto correlationYoshiguchi et al. 2004

Number density of sources~10-5 Mpc-3

Shower maximum Xmax

Fe P

Atmospheric depth

Num

ber

of s

how

er p

arti

cles

ρμ(1000) distributionby AGASA 2002

Akeno 1km2 (A1): Hayashida et al. ’95 Haverah Park (HP): Ave et al. ’03Volcano Ranch (VR): Dova et al. (ICRC ‘03)HiRes (HiRes): Archbold et al. (ICRC ‘03)

A1: PRELIMINARY

1017.5eV – 1019eV (Akeno 1km2 array)

Gradual lightening

Above 1019eV (AGASA)

Fe frac.: <40% (@90% CL)

Chemical composition study by muons(p+Fe composition assumption; AIRES+QGSJET)

PRELIMINARY

Limits on gamma-ray fraction

Gamma-ray fraction upper limits (@90%CL)

34% (>1019eV)(/p<0.45)

56% (>1019.5eV)(/p<1.27)

to observed events Topological defects (Sigl et al. ‘01) (Mx=1016[eV]; flux normalised@1020eV )Z-burst model(Sigl et al. ‘01)(Flux normalised@1020eV)

SHDM-model (Berezinski et al. ‘98) (Mx=1014[eV]; flux normalised@1019eV )

Assuming 2-comp. (p+gamma-ray) primaries

Fly’s Eye highest energy eventHalzen and Hooper 2002

HE and UHE Neutrino flux D.Tress and A.Anchordoqui 2004

SummarySuper GZK particles exist AGASA HiRes statistically consistent Origin of UHECR (Possible scenario)

Decay of Heavy Relics in our Halo (WIMPZILLA) Z-burst by EHE neutrino almost dead Violation of Special Relativity AGNs, BL-Lacs, GRBs

Super GZK particles; no evidence for gamma rays May be difficult for top-down scenarios

Evidence for point sources of UHECR AGASA HiRes statistically consistent Clusters nice chance to solve the origin of UHECRs Auger/EUSO – energy spectrum in each point source