AGASA results Anisotropy of EHE CR arrival direction distribution M. Teshima ICRR, U of Tokyo

Contents Anisotropy at eV Good evidence for Galactic Cosmic Rays Anisotropy above eV Clusters in the arrival directions New Astrophysics

Cosmic Ray Propagation in our Galaxy Deflection angle < 1 degree at eV Neutrons can travel galactic scale without decaying above eV By M.Takeda

Candidates for C.R. accelerator Pulsar SNRA.G.N. GRB Radio Galaxy Lobe

Anisotropy at eV Data A20: (~12km2) for 5years AGASA(~100km2) for 10years Event selection Core Location: inside the array Nhit >= 6 detectors χ core 2 <5.0, χ dir 2 <5.0 Number of Events 284,000 events (>10 17 eV)

First Harmonic Analysis (Sep.1986-May.2001, 284,416 events)

Galactic Cosmic Rays up to eV ●Use 284,000events over 15yrs operation by AGASA+AGASA Prototype ● >4σ near G.C. and -4σ near A.G.C. Amplitude ~4%Statistical Significance

Point Sources or Cosmic Ray flow

Dipole (G.C.-AGC) distribution Log(E) = G.C Anti G.C.

DC excess with 6 degrees rad. Aperture Log(E) =

Auto-correlation at

Conclusion Harmonic Analysis, Global excess map (p.s. = 20 o ) Pch < (consistent with previous reports) 4 σ near the GC and -4σ near AGC The anisotropy of cosmic ray arrival direction at eV observed by AGASA can be fitted with dipole distribution (GC --- AGC) Point source analysis(p.s. = 6 o ), Self-correlation analysis No evidence for point sources. The data favors the diffuse sources.

Arrival Direction Distribution Arrival directions of 59events > 4 x10 19 eV observed by AGASA No Large Scale Anisotropy. Event Clusters: 1Triplet and 6 doublets P(chance) ~ 0.07%. Interacting Galaxy VV141 in the direction of triplet at 100Mpc.

Arrival Direction Distribution Compact sources!! ~5 sigma effect

The number of point sources Assume the same intensity sources, fit the multiplicity distribution 120 – 430 sources

V 1 - V 2 plot in Galactic coordinate Outer Galaxy region |b II |<60, 90<l II <180 Log(E)> From eV 2. Extended linearly Δ ｂ II Δ ｌ II 20 o x20 o

The polarization angle 3.5σ at 40 degrees 1.8 degree x 10 degree box eV

Cosmic Ray propagation in Galactic Magnetic Field By Stanev Δ ｂ II Δ ｌ II Aperture

Linearly extended halo in 2-D correlation map can be understood as deflected charged particles by G.M.F. Magnetic field in disk Axial Symmetric  Bi-symmetric Parity Even  Odd Magnetic field in Halo Strength Bz~0.3μG Parity Odd  Even Restrict G.M.F. structures (by GMT and MT) Trace back cosmic rays up to Galactic Halo surface of 20kpc Identify sources!! On going

>19.0 >19.6>19.5>19.4 >19.3>19.2>19.1 >19.7 Self-correlation 2D-map (20 o x20 o )

Differential Energy Spectrum of pair events (bin width = 0.2 decade) X2.95X1.51 X2.04X2.63 Structure? dF/dE ~ E

Correlation as func. Of energy ratio between two events x1.86 ( ) x4.46 ( ) X2.4 He ? ?

Possible Scenario P BCNO He Rigidity dependent? Photo-disintegration cutoff? First bump --- 1ry and 2ndry p/n Second bump --- 1ry He Third bump --- 1ry BCNO Fe Naturally, Fe is expected at 2-3x10 20 eV. p.d.

Monte Carlo Realization By T.Yamamoto et al Preliminary Uniform Source Standard Chem. Comp. 10nG Magnetic Field Require Clustering

Conclusion (>10 19 eV) Clear evidence for point sources of EHECR Elongated shaped excess of ~10°in 2-D correlation map Consistent with the charged particle deflection by G.M.F. Interesting structures in the energy spectrum of cluster events (Three bumps?) Consistent with P, He, BCNO composition The beginning of the EHECR astronomy

To the future Clusters give you important information Sources (Fe primary favors GRB remnants) the chemical composition study for super GZK particle is important G.M.F. structure can be uniquely solved Constrain the inter-galactic Magnetic Field 4πcoverage of sky is really important Northern Hemisphere; Easy to understand G.M.F. structure, because it is simple toward outer galaxy. Southern hemisphere; Observation is essentially important to understand whole G.M.F. structure.

Systematics and Resolution In Mono analysis CompositionProton/Fe??? InteractionQGSJET/SIBYLL Scale height of Mie layer In Atmosphere (In Mie Scattering) Horizontal attenuation Scale height 1-D model  reality (locality) E (Rp) dependence 10,000km 2 sr  100% efficiency upto Rp ~ 40km