EHE Cosmic Rays (HE1.4, 1.5, 2.1)

Shigeru YoshidaDepartment of Physics

Chiba University

29th ICRC Pune

No GZK ?

When I was a rapporteur 6 years ago (ICRC Salt Lake)

7 events above 1020 eV

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Anisotropy : UHECR Sky?

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New measurements

HiRes Two FD Eyes allows STEREO

observation

• HiRes1 Most statistics above 10 EeV Only 1 ring• HiRes2 Lower Threshold Energy (~0.2 EeV) 2 rings

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New measurements

Auger SD (Ground Array) + 3(+1) FD Eyes

• SD 50% Completed ~1500 km2

• FD 3 Eyes completed mostly for Energy Calibration

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Present Exposure @ 1019 eV

HiRes1 (mono) ~5000 km2 sr yr

HiRes (Stereo) ~2500 km2 sr yr Auger 1750 km2 sr

yr ~ AGASA

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HiRes ApertureHiRes Aperture

Stereo data: best resolution, optimized for E>31018eV Uses time-dependent calibration of detector and atmosphere

HiRes-2 monocular: can reach down to as low as 1017.2eV

HiRes-1 monocular data began ~3 years earlier: largest statistics,

Uses profile constrained fit (PFC) unreliable <1018.5eV

HiRes-2 monoHiRes-1 monoHiRes stereo

HiRes Apertures

Wayne Springer (this conference)

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HiRes 1 (mono)

• Expect 42.8 events• Observe 15 events• ~ 5

“GZK” Statistics

Bergman (this conference)

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HiRes 1 (mono)

Integral Spectrum

Flux attenuation startsAt around 1019.75 eV

Consistent with the GZK hypothesis

Bergman (this conference)

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You need some caution

HiRes1 is strongly BIASED measurement.

It’s MONOCULAR and only 1 ring! Viewing limited volume

of the atmospheric volume.

Aperture continues increasing with energy

Profile constrained fit to estimate energy

Stereo measur. should provide a confident data

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HiRes Stereo Flux

Fit to power law. Single index

gives poor chi2 Evidence for

changing index

Wayne Springer (this conference)

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HiRes Stereo (and others)

Exhibits cutoff structure

Expect 33.7 events

Observe 9 events ~4.8 Some details

DIFFERENT from mono!

The Mono spectrum may contain unknown syst.

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Some Remarks

HiRes Stereo Cut “sort of” narrow Opening angle events

Require careful estimation of detect. Eff.

Scanning simple parameters continues

AGASA conflicts Energy scale? Old MC?

Auger Hybrid measurement

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Auger Hybrid

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Log (E) = -0.79 + 1.06 Log(S38)

E = 0.16 S381.06

(E in EeV, S38 in VEM)

Uncertainty in this rule increases from 15% at 3 EeV to 40% at 100 EeV

Paul Sommers (this conference)

Auger SD spectrum

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Paul Sommers (this conference)

Energy scale uncer. still large

~40 % in 100 EeV improvement will

come soon

S(1000): The energy indicator

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(Ghia, this conference)

S(1000): The energy indicator

Less mass composition sensitive Not just muons but emg component make sizable

contributions (Alan Watson, private comminication)

S(1000)Fe-P ~10 % difference (Paul Sommers, private com)

s(1000) ~15% @ 10 VEM (Ghia, this conference)

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BUT ALL these rely on EAS MC!!

S.Yoshida

A scary scenario

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When more statistics

Intrinsic fluctuationOf EAS development!!

LHCfinteraction point

140m96mm

The beam pipes of LHC are separated by 96mm at 140m from the interaction point.

Charged particles are swept out by magnets.

LHCf measures the distribution of the Feynman x parameter (practically energy) of neutral particles emitted in the very forward region using position sensitive calorimeters placed in this 96mm gap.

(Sako, this conference)

LHCf Prototype test

Silicon tracker for position calibration

Main detector

Beam

Event cluster > 40 EeV

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(Westerhoff, this conference)

No significant excess: AGASA’s triplet Pch ~0.28

AGASA triplet story

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(Westerhoff, this conference)

One event added – BUT below 40 EeV!!

180° 170°

6060

180° 170°

60° HiRes stereo event

HiRes: BL Lac correlation?

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“BL” BL Lacs with m<18, all HiRes events (no energy cut):

F = 2×10-4

All confirmed BL Lacs (“BL+HP”) with m<18, HiRes E>10 EeV:

F = 10-5

Confirmed TeV blazars, all HiRes events (no energy cut):

F = 10-3

These are not independent results: the samples overlap.

Analysis has been a posteriori, so F values are not true chance probabilities. (Finley, this conference)

HiRes2 Mono: Galactic anti-center?

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(Thomson, this conference)

Coverage Significance (1.5º)

Significance (3.7º) Significance (13.3º)

300 270 240

3.0

2.0

1.0

0.0

-1.0

-2.0

-3.0

Auger: Galactic Center29th ICRC Pune(Letessier-Selvon, this conference)

Filled circles, HiRes; Triangles,HiRes/MIA, Open circles, Fly’s Eye (shifted).

Mass Compositon (Xmax)

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(Sokolsky, this conference)

HiRes+Fly’sEye(shifted)

LightHeavyLight?

1EeV

Particle Physics Outputs

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(Mathews, this conference)

mbsyssysstatAirpin )(11)(39)(17456 :HiRes

So What we have seen?

GZK strikes back! Needs cautions on energy scale, but the

spectrum is consistent with the cutoff

No anisotropy…. Except some possible indication..

Deficit in anti-galactic center, BL-Lac correlation

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Then… what we can do to pin down UHECR origin ?

ADDING MORE (GOOD) DATA!

Multi WavelengthParticle spices observation

GZK photons/Neutrinos lead to information on EHE cosmic ray source

distribution, radio background, and extragalactic B.

Photon-induced EAS search LPM + Geomagnetric Preshower effects

Xmax anomaly

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•HiRes (O’Neill, this conference)•Auger (Risse, this conference) F(E>10EeV) < 26 %

EHE Neutrino Observatory

Deeply penetrating inclined EAS search Auger (Nellon, this conference) HiRes ….

IceCube (In-ice Cherenkov light detector) (Chirkin, this conference) Rice (In-ice Cherenkov Radio detector) ANITA (In-Flight Cherenkov Radio detector) (Duvernois, this conference)

Acoustic Extension (In-ice Acoustic detector) (Nahanhauer, this conference)

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IceCube

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1km3!

Deep Ice Array

IceTop

(Chirkin, this conference)

IceCube

Conventional Technique extends up to EHE!

1EeV 300 PeV cascade

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IceCube

Yoshida et al PRD 69 103004 (2004)

“Hybrid” tech to extend ++1km3

“conventional” detector provides “test” beam!

Use IceCube holes

3 distant holesdown to 400 m

7 stations per hole

sensor, transmitter, auxiliary det. per station

Deployment January 2006

Results

Summer 2006

Rolf Nahanhauer (this conference)

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Future Outlook

Auger: 7 x AGASA by 30th ICRC HiRes: <2 years STEREO data to be

analyzed. ~70% more statistics

“independent” dataset for testing the “BL Lac” New observatory in the Northern sky Telescope Array

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576 plastic scintillation Surface Detectors (SD)

Atmospheric fluorescence telescope3 stations

20km

Telescope Array

1.2km spacing

3m2 1.2cm ttwo layers

Black Rock Mesa

Long Ridge

Middle Drum

SD

FD

5 communicationtowers

Sensitivity of SD : ~9 x AGASA

Test Observations @ Millard county, Utah

An observed shower-like track (11 July, 2005)

ch# Recorded waveforms

Relative time

dc

cc

ba

aa

99

89

78

68

57

46

35

Typical waveform with fluorescence light(RUN65,TRIG165, CH89)

3-13 July, 2005 @ Black Rock Mesa site

Single telescope with 256ch PMTs camera

Total observation time: 31.5 hours

1st level trigger threshold: 6 - 6.5 sigma

Trigger rate: 0.6 - 1.5 Hz

5 ADC count = 2.5 p.e./100 ns

preliminary

SDP

logE(eV) = 18.05

Xmax = 674.9 g/cm2

= 46.2o

Analysis resultdegree

degree

(Ogio, this conference)

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Future Outlook

Auger: 7 x AGASA by 30th ICRC HiRes: <2 years STEREO data to be

analyzed. ~70% more statistics

“independent” dataset for testing the “BL Lac” New observatory in the Northern sky Telescope Array

29th ICRC Pune

• EHE gamma ray/Neutrino search EAS detector, IceCube, Rice, ANITA etc.

Thank you!

Nos vemos en Mejico!!

29th ICRC Pune

S.Yoshida