Observation of the universe's highest energetic
particles and a next-generation observatory

Toshihiro Fujii(fujii@icrr.u-tokyo.ac.jp)
ICEHAP seminar
2017/July/28
Image from Quanta magazine12This is how scientists see the world.
credit: http://abstrusegoose.com

3This is how scientists see the world.
credit: http://abstrusegoose.com

4This is how scientists see the world.
credit: http://abstrusegoose.com

Cosmic Rays

5

What are Cosmic Rays?

In

Proton(90%), Helium(8%)
and heavier nuclei

seDiscovered by V. F. Hess (1912)

creaRadiations

Energetic particles injected from the universe.

E > 1019 eV, ultrahigh-energy
cosmic rays (UHECR)

Altitude [km]Anniversary on Aug. 7th 2012

Landing at Bad saarow, Germany on
Aug. 7th, 1912

Grandson of Hess

Memorial Stone

6

Cosmic Ray Anniversary on Aug. 7th 20127

Anatoli

8Physics goal of UHECR Astrophysics
The origin and nature of ultrahigh-energy
cosmic rays (UHECRs) and particle
interactions at the highest energies
How frequent?
What kind of particle?
Where come from?
9How frequent?: Energy spectrum

2.5
E J(E)Knee-2-1
1 km yr

Larger energy
than the largest
accelerator
(LHC)
-2
-1
1 km century-2-1
1 m yrAnkle

Very infrequent,a large sensitive
area needed10he LAT instrument, the bulk of the
500 MeV. IC 443 is located in they emission produced by the pool of
weak relative to the region aroundeminga pulsar (2FGL J0633.9+1746)
2.5
map, W44 is the dominant source

synchrotron radiation seen in a high-resolution
radio continuum map of W44 (26) support thispicture. High-energy particles in the “crushedcloud” can be explained by reacceleration of thepreexisting galactic cosmic rays (25) and/or freshly accelerated particles that have entered thedense region (20). The mass of the shocked gas

20
Acceleration Scenario toward 10 eV
E

J(E)

Hillas&plot

B

C 443

W44
E2 dN/dE (erg cm-2 s-1)

10 -10Extragalactic origin?
Bottom-up model

10 -111

Galactic origin
Supernova remnants
IC443

10 -1281012

as measured
W44
ote thebesthaded bands
eling of thepoints for IC
ote the bestSCIENCE

10

Neutron stars, Active
galactic nuclei, Gamma
ray bursts, Radiogalaxies, Galactic
clusters

Best-fit broken power law
Fermi-LAT
AGILE (19)π0-decay
Bremsstrahlung
Bremsstrahlung with Break
9

10

10

10

Energy (eV)

1011

1012

Top-down model

fit pion-decay gamma-ray spectra, dashed lines denote the best-fit bremsstrahAnnihilation/decayoflung spectra, and dash-dotted lines denote the best-fit bremsstrahlung spectra
super heavy relic
when including an ad hoc low-energy break at 300 MeV c−1 in the electron
spectrum. These fits were done to the Fermi LAT data alone (not taking the TeV
particles, Topological
data points into account). Magenta stars denote measurements from the AGILE
defect, magnetic
satellite for these two SNRs, taken from (31) and (19), respectively.
VOL 339

15 FEBRUARY 2013

monopole, Z-burst
model
809

γ : Lorentz factor of shock
Z : atomic number
B : magnetic field strength
R : size

Greisen-Zatsepin-Kuzmin (GZK) Cutoff
Cosmic'microwave'
background'radia5on'(CMBR)'
Cosmic'Ray

Earth
Cosmic'Ray

Interaction between UHE protons with energies above 1019.75 eV and CMBR via apion production. Heaver nuclei also interact with CMBR via photo-disintegration.
Mean free path : 50-100 Mpc (Nearby sources compared to the universe size)

1 pc = 3.26 l.y. ~ 3×1016 m

Flux × E3/1024 (eV2 m-2 sr-1 s-1)

19.7
Expect suppression of flux above 10 eV.

Planck 201310
Preliminary

1
TA ICRC 2015
Auger ICRC 2015
-11017.5

18

18.5
19
19.5
log (E (eV))
10

20

20.5

12

Theoretic models of ankle structure

Dip model

Ankle modelProton only

ProtonIron

Suppression = GZK cutoff

Suppression= acceleration limit
Fig. 2. Same as Fig. 1, for model B (pure proton EGCR
sources).
The
injection
specFIGURE 5. UHECR spectrum in a two component mode
tral index is x = 2.6 for the HiRes data (left) and x = 2.7
forprotons
the Akeno/AGASA
datathe injection power law index i
with
and
Iron
nuclei,Observed“ankle”=paircreation
“dip”
Ankle
structure=transitionoforigins(right). Two different propagated spectra and the corresponding
inferred
GCR
component
γg = 2.0 and the maximum energy is Emax = 4Z × 1018 eV.
are shown, for an injection spectrum either with or without a low energy cut (see text).
Transition takes place well before theNot “dip”“ankle”.
In each case, we show the resulting Galactic component necessary to account for

because the effect of galactic magnetic field will sub
the observed fluxes
in thecompositiontransition region. Inmeasurement
the first case (no break),the EGCR
Mass
needed.
stantially deviate the nuclei trajectories at the highest en
17
component appears to dominate down to 3 10 eV if one refers to the HiRes data
13
D. Allard et al., Astropart.Phys. 27 (2007) 61-75,
R.
Aloisioetal.
Astropart.
Phys.
34(2011)
620–626
ergies
[11].
For
these
reasons
the
model
at
hand,
whil
17

UHECR Astronomy

COMPOSITION / MAGNETIC FIELDS

Magnetic Field (Gauss)

SOURCES

Flux suppression → Nearby Universe → Large scale structure
Deflections

High-energy astrophysics

~
Z/E
Small
deflection
galactic/extragalactic magnetic field> ThreeUHECR
messengers are→available
to study
the non-thermalin
universe.

Size
Photons

Mean Energy (eV)Charged particles:
Hillasplot
p, Z, e±GZK HORIZON Correlation with

Nearby sources
Neutrinos↓
UHECR(Cronin TAUP 2013)
Interaction with CMB → Sources within ~ 100 Mpc
Astronomy
Propagation distance (Mpc)
14
Expect flux suppression and anisotropy of light component

Extra-galactic?
AGNs? GRBs?
…?

Image credit : M. Ackermann @ TAUP2013

How to detect very infrequentUHECRs?
= Extensive air shower (EAS)

Image credit: ASPERA/Novapix/L.Bret

15

How to observe extensive air shower (EAS)
Longitudinal Development

Fluorescence
detector (FD)

Xmax

Surface detector
array (SD)
Lateral Density Distribution
CORSIKA software

https://web.ikp.kit.edu/corsika/movies

16Mass composition measurement using Xmax
longitudinaldevelopments forProton and Iron
primaries.

With the same energy, E
Proton(1) Iron(56)Average
900
850

QGSJetII-03
QGSJet01

800

SIBYLL 2.1
QGSJetII-04

100
CORSIKA Prediction

ProtonProton QGSII04
Iron QGSII04

EPOS-LHC

750
700

Iron

650

60

50% proton 50% Iron40

18.9 < logE < 19.1

20

600
550
17

Distribution

80
Entries<Xmax> (g/cm2)

E

E/56

0
600 650 700 750 800 850 900 950 1000 1050 1100
17.5

18

18.5
19
log10(E (eV))

19.5

20

Xmax [g/cm2]

17

Fluorescence detector (FD)

Detecting fluorescence photons emitted fromatmospheric molecule excited by EAS.

Measuring longitudinal development of EAS
including Xmax = sensitive to mass composition
Only moonless clear night, duty cycle, 10~15%
less dependence on hadronic interaction model.
Many calibration factors: atmosphere, mirror
reflectance, filter transparency, PMT gain.

18ᖺ ࡟ ࢫ ࢱࢺࡋࡓࠋࡑ ࡢ タ ィࡢ ㅖ ࣃ ࣛ ࣓ࢱࡣ

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ࠋ

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ࠋ

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College
Iwate Prefectural University Miyako College

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plane of Fresnel lens/mirror to observe
fluorescence light.

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RF[㸧

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72.<2 Ѹ㸪
72.<2 Ѹ 㸧ࠉ ࠉ ࠉ㸦

Iwate Prefectural University Miyako College

Observe longitudinal profile including Xmax
to be sensitive to the mass composition ofcosmic ray.

Iwate Prefectural University Miyako College

In 1969, first detection offluorescence light by TOKYO-1(Tanahashi et al. @Doudaira
Observatory, Japan)୍ ୍
Reference: 空気シャワー観測による宇宙線研究の歴史
永野元彦, 大気の蛍光観測による宇宙線実験の始まり 棚橋五郎

19P ࠊPPࣆ ࢵ ࢳ ࡛ ษ ๐ ࡋ ࡓ ࠋ ࢸ ࣞ ࢫ ࢥ ࣮┤ ᚄ 㸪

㸬
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Candidates observed by TOKYO-1 (1969)
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୍1NII-Electronicᕤ ᕤ (OHRWURQLR
Library ࠉService
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Fluorescence
dominated

In the upgrade detector ofTOKYO-3, the 4 m2 lens
was unfortunately UVprotected one.
Fly’s Eye experiment,
Telescope Array experimentand Pierre Auger
Observatory established thefluorescence technique andreported physics results.

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͂Ȣ 㹻

ࠉ ➨  ᅗࠉ ࣉ ࣛ ࢫ ࢳ ࢵ ࢡ ࣞ ࣥ ࢬ ࡢ ග ㏱ 㐣ᛶ ⬟72.<2 Ѹ㸪
72.<2 Ѹ㸪
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M. Ave et al. / Astroparticle Physics 28 (2007) 41–57

Airfly (2007)

x 10 2
1500

CountsࠉࠋThe event is consistent with ⱼthe fluorescence-dominated5
shower with 5×1018 eV, 680 ᆶ2g/cm (B. Dawson, arXiv:
1112.5686).
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0
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Wavelength (nm)Fig. 4. Measured fluorescence spectrum in dry air at 800 hPa and 293 K.

Table 1
Measured fluorescence band intensities in dry air at 800 hPa pressure and 293 K temperature20ࡉSurface detector array (SD)

Observing EAS particles on the ground by SD
array
Measuring lateral density distributions
24 hour, 365 days operation, Duty cycle~100%
A large systematic uncertainty due to hadroninteraction models.

21

UHECR observatories
Telescope Array Experiment(TA)
Utah, USA2
2
700 km (→ 3,000 km )~7 events/year (→ 30)

Pierre Auger
Observatory (Auger)
Malargue, Argentina
23,000 km

Google Earth~30 events/year22Telescope Array Experiment (TA)

Largest cosmic ray detector in the Northern hemisphere2~ 700 km at Utah, USA
Fluorescence detector + Surface detector array

Fluorescence Detector at BRM and LR stations
Surface Detector Array2) + 256 Photomultiplier
Spherical
segment
mirror(6.8
m
507 Scintillator, 1.2 km spacing
tube(PMTs)/camera, 12 newly designed telescopes

Fluorescence detector
at MD station
Refurbishedfrom HiRes experiment,
2
Spherical mirror 5.2 m ,256 PMTs/camera,
14 telescopes

16×16
PMTs
PMT

23

Delta, Utah, USA

Cow

24

Pierre Auger Observatory (Auger)

The Pierre Auger Observatory
The Pierre Auger Observatory

2
The world’s largest UHECR observatory 3000 km
The Pierre Auger Observatory

13

array of 750 m,
io antennaInfill
array
array of 750 m,
Radio antenna array- )andcompletedin 2008
The Pierre(2004
Auger
Observatory
LIDARslaser
facilities
LIDARs and laser facilities
The Pierre Auger Observatory Surface Detector (SD)
Water Cherenkov Tank
Infill array of 750 m,
1.5km
spacing,
1600
LIDARs and laser facilities
Radio antenna array
ay of 750 m,
1665stations
surface detectors:
LIDARsand laser facilities
ntennaarray
ionwater-Cherenkov
1665tanks
surface detectors:
es High elevation(grid of
1.5 km,3000 km )Fluorescence
Detector (FD)water-Cherenkov
tanks
telescopes(grid of 1.5 km, 3000 km )3.4 m spherical mirror, 440 PMT, 30° × 30° FOV
light guide + collector ring, 4 × 6 telescope
(a)

2

2

High elevation
telescopes

1665 surface detectors:
water-Cherenkov tanks
4 fluorescence detectors(grid of 1.5 km, 3000 km2)
(24 telescopes
in total)
4 fluorescence
detectors(24 telescopes in total)

Figure 3.2: (a) Schematic depiction of a surface detector station [28]; (b) a surface
detector station deployed in the field.

tubes (PMTs) are optically coupled to the water and symmetrically positioned on
top of the tank with a distance of 1.2 m between each other. Each detector is de1665vised
surfaceto work detectors:
completely stand-alone, thus, every tank is equipped with a battery
box and a solar powersystem providing the 10 W average power required for thewater-Cherenkov
tanks
electronics [29]. A GPS (Global
Positioning System) unit is installed at each2)
(grid tank
of
1.5
km,
3000
km
tank as a basis for time synchronization between the detector and the Central Data
Acquisition System (CDAS) as well as for providing precise information about the
tank’s position. The communication between the detector and the CDAS is achieved
wirelessly via one of the four communication beacons located near the FD sites atthe perimeter of the array.

Southern hemisphere:
20
Province Mendoza,
Argentina
Southernhemisphere:
Province Mendoza, Argentina 20

4 fluorescence detectors(b)

4 fluorescence detectors(24 telescopes in total)

To detect charged particles from extensive air showers, the Cherenkov e↵ect is exploited [30]. When the velocity of a charged particle traversing a medium is greaterthan the speed of light in this medium, Cherenkov light is emitted by this particle ina cone along its trajectory. The Cherenkov light produced in the tank by secondary
particles from extensive air showers, mostly muons and electrons, is detected by the
PMTs mounted on top of the tank and converted into a current pulse. To increase
the amount of Cherenkov light collected, a reflective layer of high-density polyethylene fabric covers the inside of the tank. The signals from the PMTs are read out
and digitized by Flash Analog-to-Digital Converters (FADCs) at a rate of 40 million

25

Malargüe, Mendoza,
Argentina
Goat

26

Annual parade and AugerPrime 2015 ceremony
Yoshida-san

Yoshida-san

27

Scale of UHECR Observatory28

Scale of UHECR Observatory29

Scale of UHECR Observatory30

An
observed
event
Reconstructing the air shower
Hybrid observation (FD+SD)

Reconstructing the air shower

FD

Loma Amarilla

Coihueco

SD vertical energy calibration with FD

Los Leones

Los Morados
8

Calibrated by EFD Xth Rencontres du Vietnam, Quy Nhon August 2
ESD/EFD
data
0.2

proton
iron

0.15

0.1

SD

0.05

0

0.5

1

1.5

2

E /E

31

Intermediate summary
Ultrahigh-energy cosmic rays (UHECRs) are most energetic particles in the universe.
This energy is much larger than human-made accelerator in ground. But very infrequentas 1 particle km-2 century-1. Very large coverage required to detect UHECRs.
19.7
GZK cutoff is expected above cosmic rays with energy of 10 eV.

Small deflection of UHECR will provide us a next-generation astronomy.
Three important measurements: energy spectrum, mass composition, arrival direction
Measurements of extensive air shower induced by UHECR with the hybrid detector (SDand FD).
2
The largest cosmic-ray observatories in operation: Telescope Array experiment (700 km ,2USA) Pierre Auger Observatory (3000 km , Argentina)

32

Quick question?

Photography : Steven Saffi, Production assistant : Max Malacari

http://vimeo.com/88029390

33

Recent Results in ICRC2017

34

TA/Auger
exposurecomparison
TA and Auger
UHE Exposureace Detectors

Auger Anisotropy ICRC17: 9.0⇥104 km2 sr yrAuger Spectrum ICRC17: 6.7⇥104 km2 sr yr

Pierre Auger: 3000 km2

scope Array:700 km2

TA Spectrum ICRC17:0.8⇥104 km2 sr yr

AGASA

M. Unger in ICRC 2017

[5 of 30]

35

Energy Spectrum

Auger energy spectrum
Combined Energy Spectrum

E /eV
1020

1018
2 sr 1 yr 1

1019

eV km

1038

1036

1 =

3. 2 9

3±

1019

0. 00

2±

0. 05

2

=

1020

3
2.5

±

2
0. 0

±

0. 1

Eankle = (5.08 ± 0.06 ± 0.8) EeV

2

1037

1038

SD-1500 vertical
SD-750 verticalHybrid
SD-1500 m inclined

17.5

18.0

18.5

1037

3
E J ( E)/

E3 J ( E ) /2

eV km 2 sr 1 yr 1

1018

E /eV

19.0

19.5

20.0

20.5

Es = (39 ± 2 ± 8) EeV
E1/2 = (23 ± 1 ± 4) EeV

Auger (ICRC 2017)17.5

lg( E/eV)

18.0

18.5

19.0

19.5

20.0

lg( E/eV)[8 of 30]

Update atmospheric analysis and geometry, +1% ~ +4%

F. Fenu, M. Unger in ICRC 201736

TA energy spectrum“Full-Range” TA Spectrum

Power-Law Fit

T. AbuZayyad, CRI126

TA ICRC2017 Preliminary
logEsup = 19.81 ± 0.04

E 3.27±0.03

E

0.0
±
9
6
.
2

2

E
4.

logEank = 18.69 ± 0.02

63
.
±0
49

Nexp (no suppression): 79.8
Nobs: 26
Prob.: 2.2x10-12, 6.92 σ
13

11

T. AbuZayyad, Y. Tsunesada in ICRC 201737

CommonDeclination
Band
EntireSky
SpectraSpectrum discrepancy at highest energies
Entire skies of Auger and TA

Common declination band

Auger-TA Common Declination
Band Spectrum Analysis•

Restrict δ to [-15o ,24.8o] range••

Excludes TA hot spot

Rescaled to fit the ankle spectrum.
Better agreement between TA and Auger

Inependence of exposure on
declination (aka “1/ω method”):
10in the common declination band

11

Spectrum
discrepancy at the highest energies.
𝐽
/

1
𝐸 =
ΔΩΔ𝐸

1
ω(δ )

(UHECR 2016 proceedings)

Good agreement if we select events in the common declination band,

Northern/southern hemisphere difference or detector systematics.
D. Ivanov in ICRC 201738

Declination Dependence in TA

Declination dependence?

No declination dependence in Auger.
•
3.9σ
effectinTA
using
broken
power
law
fit
3.9σ difference of the fitted broken energies in TA.

•

Auger sees no significant declination dependence
D. Ivanov in ICRC 201739

Pioneering measurements by TASD and Auger water tank

10
Preliminary

2014/Nov/28 15:43:01.453549
Event display with SD waveforms

FADC count

Flux × E3/1024 (eV2 m-2 sr-1 s-1)

Detector exchange to understand the discrepancy
Energy: 3.04 EeV, zenith: 46.8 deg (Preliminary)
1
DET
1219

TA Combined 2015
Auger ICRC 2013 +8.5%-11017.5

18

18.5
19
19.5
20
20.5
Surface Detectors of the Pierre Auger Observatory and the Telescope Arraylog (E (eV))

DET1218
Upper
Lower

Showerdiretion

Bin number (each 20ns)

Water
tank

DET
1317

DET1318

10

DET
1118

Practical implementation
4.2. THE SCINTILLATOR DETECTOR

69

60

R.
Takeishietal.,
ICRC2015,
he two Auger SD stations deployed at the TA Central Laser Facility.

AugerPrime

Figure 4.12: 3D view of the SSD module with the support bars. The bars are connected to the tankusing lifting lugs present in the tank structure.

4.2.7

Calibration and control system

CLF

CHAPTER 4. THE SURFACE DETECTOR

Figure 4.1: 3D view of a water-Cherenkov detector with a scintillator unit on top.

Simple and robust
construction of
detector moduleand mounting frame,
double roof forthermal insulation

Theta=46.763 E=3.037EeV Nhit=5 X=0.110km Y=1.333km

15

40

max

(combining HeCo andMass composition (Average Xmax)
62

W. Hanlon in ICRC 2017

J. Bellido in ICRC 2017

41

max

Mass composition (Xmax distribution)(combining HeCo and FD-standard)

logE=19.0

359 events
18.9<lgE<19.0

62

W. Hanlon in ICRC 2017

J. Bellido in ICRC 201742

Xmax Compatibility Table< log (E/eV) < 19.0
Summary from Xmax 18.2
working
group
10

Auger
Data
Mean = 744
RMS = 66

Xmax

Auger

TA Detector Simulation

Compatible

Incompatible

Mean = 738
RMS = 60

Proton
Mixed
only

TA

Xmax (Auger)

Iron
only

Auger

Auger

TA Analysis

7

TA

We present thesolution for a
decade-longcontroversy.

!!!

Take away message
TA and Augercomposition measurements (Xmax)
agree within the systematics
V. de Souza in ICRC 201743
18.2 < log10(E/eV) < 19.0

EAS with Re-tuned CR Models : Xmax

Elongation rate

After
LHC :rate
Elongation

Sibyll shifted by ~+20 g/cm2

Verysimilarelongation
rate(slope)forall
18
for other models about the same <Xmax> value at 10 eV but
2post-LHC models, ~ 50 g/cm /decadeslope increased for QGSJETII

minimum given by QGSJetII-04

slope decreased for EPOS

maximumvery similar elongation rate (slope) for allmodels given by Sibyll 2.3c 40gr/cm2
70gr/cm2

Preliminary
11

Elongation rates indicate a transitionof the mass composition.
J. Bellido in ICRC 2017

T. Pierog in ICRC 201744

Xmax distributions(FD)
Interpreting Xmax distributions with QGSJETII-04

four components composition modelProton, Helium, Nitrogen and Iron

20

J. Bellido in ICRC 2017

Sum of four components

2045Composition fractions(obtained from fits to the Xmax distributions)21

J. Bellido in ICRC 2017

21

46

The <Delta
MethodThe
Δ>
MethodThe <Delta
MethodThe
Δ > Method

11

Mass composition using Auger SD

Cosmic Rays Introduction
The Risetime and the Observable <Δ>
Hadronic Interaction with the <Δ> Method
Mass composition with the <Δ> Methodby the integrated signal of the
18-07-2017
he 10% to 50%
of its total value

18-07-2017

N: number of detectors in an event
N: number of detectors in an event

t1/2 [ns]t1/2 [ns]Signal [VEM peak]

The Risetime, t1/2

11This method
combines risetimes from individual detectors into one
This methodobservablecombines risetimes
fromtheindividual
detectors into one
representing
whole event.
observable representing the whole event.

600

The risetime is the time taken by the integrated
600
10Total Signal
benc
signal of thesurfacedetectors
to
rise
from
10%
to
The
risetime
is
the
time
taken
by
the
integrated
signal
of
the
δ
=
t
−
t
1/2
i
1/2
1/2benc
E.M. Component
500
δ
=
t
−
t1/2
50%
of its total
surfacedetectors
to risevalue
from the 10% to 50% of its total
value
i
1/2
Muoninc Component
8500

The Risetime, tCalibration with Hybrid Events

zenith angle

Graph
20
40

0
0

Xmax [g cm-2 ]300

750 m array

r [m]

600

1100

60

Graph
1500
m
array
1500
m
array
750
m
array
1100
The
Δs is the average deviation of risetimes within an
1.30observable< sec θ < 1.40
1.00 < sec θ < 1.10

80
100
time [25 ns]

Xmax [g cm-2 ]400〈t1/2 〉 [ns]〈t1/2 〉 [ns]This definition makes it sensitive to themuon-to-electron ratio of the total signal

6

4

2

0
200

2

2

44

400

0.5

600

QGSJetII-04
800 1000
E = 10 EeV

1200 1400 1600r [m]

θ = 30 º
r = 1000 m

0

3
iron

-0.5

20

-1.5

300

800

0.5

800

200 0

iron

700

700

100-0.5

600

-1
0
0

〈 ∆s 〉The observable Δs is the average deviation of risetimes within an
event
from
the
expected
averagerisetime:
885 events
event
from
the
expected
averagerisetime:
252
events500
10 200nThis definition
makes it sensitive to the muon-toto
750
mSignalarray
1500 m array
Total
1000
1000
pro
1.5
1.5
the
electron ratio of the total signal
thebenchmark
benchmarkE.M. Component
Dependenceon
Benchmark Bin
Benchmark
Bin
100
n
400
o
after
uncertainties
Muon Componentt
8
afteraccounting
accountingfor
formeasurement
measurement
uncertainties
pro
900
900
1
1
19.0 < log(E/eV) <19.2
zenith angle〈 ∆s 〉

Signal [VEM peak]

100
ns]

Signal [VEM peak]

400
The
risetime
is the time taken by the integrated
400With the calibration we obtain a surrogate of Xmax for the selected SD events
10
Total Signal
signal of thesurface detectors to rise from 10% toE.M. Component
4
300
bencinformation from the
maximize
50% of its total value
300Muoninc Component
8
t1/2 −the
t1/2
benc
t
−
t
18-07-2017
Δ i = 1/2 1/2
electromagnetic
component in Δs
2
700
Δ
=
i
σσ1/2
200
6
200
Benchmarkmakes it sensitive to the1/2
Uncertainty
on the
the
1.00
<
sec
θ
<
1.10
This
definition0
BenchmarkWe
calibrate
the
Δ
using
Reconstructed
HybridEventsmeasured
Uncertainty
on
0
20
40
60
80 as
100 a function
s
600 Δ
50%
of
energystime[25 ns]risetime
100
muon-to-electron
ratio
of
the
total
signal1.30 < sec θ < 1.40
risetime
simultaneously
withthefluorescenceandthesurfacedetectors
100
4
calculated using pairssensitive to the muon-to-500
calculated using pairs
We study the evolution of the mean values of Δs as a function of energy
and twins
and twins
f the total signal
200
400
600
800 1000 1200X1400
1600
1800
2000
2
700
=
a
+
bΔ
+
clog(E/eV)
max
s
200
400
600the800
1000 1200 1400 1600 1800 2000
and we include a comparison with thosefrommodelsr [m]Dependence on
10%
6

QGSJetII-04

40

17.6

60

17.8

80
100
time [25 ns]

18

18.2

18.4

EPOS-LHC

P. Sanchez-Lucas in ICRC 201718.6 18.8
log(E/eV)

0 -1
500 200
400

600

19.0 < log(E/eV) <19.2
QGSJetII-04
Correlation = 0.39

600

800

EPOS-LHC
1000 1200
1400 1600r [m]-4 -1.5-318.6-218.8-1 19 0 19.21 19.42 19.63 19.84 20∆slog(E/eV)

Correlation = 0.46

500

3
-4

-3

-2

-1

0

1

2

3

4
∆s

10
47

Average Xmax

max

max

850

Average Xmax

Auger FD ICRC17 (prel.) ± stat.
Auger SD ICRC17 (prel.) ± stat± sys.

Fluorescence and Surface Detector

800

Auger SD ICRC17 (prel.) ± stat780

± sys.

〈Xmax〉 [g/cm ]Auger FD ICRC17 (prel.) ± stat.

65 62

2

820

2

〈Xmax〉 [g/cm ]

800

390

760
740
720

49

750

700
650

700
680
660

600

640

17

17

10

18

10

19

E [eV]

1020

10[12 of 30]

P. Sanchez-Lucas, M. Unger in ICRC 2017

10

18

10

19

E [eV]

10

20

10

19.7 eV?
Lightercompositionabove
10
lines: air shower simulations using p
48

&

&

No GZK γ and ν at highest energies
e + 3⌫

upper limits 95% CL

1Z-burstTD
SHDM ISHDM IIGZK proton I
GZK proton II

Y 2010

10−1

10−5

10−6

HP 2000
A 2002

Hy 2011

Hy 2016+syst.

Single flavour, 90% C.L.
νe : νµ : ντ = 1 : 1 : 1

Enrique Z

ANITA-II (2010) (x 1/3)

Cosmogenic ν models
p, Fermi-LAT, E =1019 eV (Ahlers '10)min
p, Fermi-LAT, E =3 1017 eV (Ahlers '10)minp, FRII & SFR (Kampert '12)
p or mixed, SFR & GRB (Kotera '10)
Fe, FRII & SFR (Kampert '12)

Auger 1 Jan 04 - 31 Mar 17

Astrophysical sources

IceCube (2015) (x 1/3)

E2 dN/dE [ GeV cm-2 s-1 sr-1 ]upper limits 95% CL-2Integral photon flux Eγ > E0 [ km sr-1 yr -1]

UHE neutrinos at Auger+

AGN ν (Murase '14)

10−7

TA 2015

10−2

10−8

10−3

10

SD 2015

1018

1019

−9

1020
E0 [eV]

1017

1018

Eν [eV]

1019

1020

1021

Top-down models are ruled out.
Figure 2: Integral upper limit (at 90% C.L.) for a diffuse neutrino flux of UHE dN/dE = kEn

2 givena normalization, k, (straight red line), and differential upper limit (see text). Limits are quoted for a singflavor assuming equal flavor ratios. Similar limits from ANITAII [8] and IceCube [9] are displayed alo
with prediction for several neutrino models (cosmogenic [10, 11, 12], astrophysical [13].)

Auger limits become sensitive to GZK-ν and γ
M. Unger in ICRC 201749

In
tension
of
the
dip
model
by
IceCubelimit
Best fit spectra
JH, Boncioli, Bustamante, Winter
ApJ 825:122 (2016)

Cosmogenic Neutrinos

JH, Boncioli, Bustamante, Winter
ApJ 825:122 (2016)> Ranges: min/max overallowed parameter space> Exceeds recent
IceCube sensitivity(# #%'#"*&)''  ! Mainly due to high source evol.

> Minimal number> Low statistics cannot distinguish > Overshoot:below
fit rangeof expected
events:5.4
source- or GZK effect> Fit driven by ankle region! Favours hard spectra....

!! Minimal
escape1-2
energy?
Background:
events! Magnetic field diffusion?

! Challenged at more than 95% C.L.

! Or further constraint on Dip model?

! … already in stress with TA data

! …and strong source evolution

Dip model excluded forreasonable source evolution!

Jonas Heinze | Dip Model / Cosmogenic Neutrinos | 19.7.2017 | Page 11

J. Heinze in ICRC 2017

Jonas Heinze | Dip Model / Cosmogenic Neutrinos | 19.7.2017 | Page 12

50

Testing hadron interaction model

Abstract: The hybrid events of the Pierre Auger Observatory are used to test the leading, LHC-tuned, hadronicinteraction models. For each of 411 well-reconstructed hybrid events collected at the Auger Observatory withenergy 1018.8 1019.2 eV, simulated events with a matching longitudinal profile have been produced using
QGSJET-II-04 and EPOS-LHC, for proton, He, N, and Fe primaries. The ground signals of simulated eventsO DE JANEIRO 2013
have a factor 1.3-1.6 deficit of hadronically-produced muons relative to observed showers, depending on whichhigh energy event generator is used, and whether the composition mix is chosen to reproduce the observed Xmax
distribution or a pure proton composition is assumed. The analysis allows for a possible overall rescaling of theenergy,is found to lie within the systematic uncertainties.
120
700 which
DATA 45°-65°
DATA 45°-65°±

RESULTS

rded at the Pierre
Auger ±Observatory
p QGSJetII-04
Auger 2017 preliminary

p QGSJetII-04
p EPOS-LHC
pPierreEPOS-LHC
Keywords:
Auger
Observatory,
ultra-highenergycosmicrays,
muons,
hadronic
interactions
100
Fe QGSJetII-04
Fe QGSJetII-04
ORATION 2 650
Fe EPOS-LHCFe EPOS-LHC
sys

µ

µ

, New York University, NY, NY 10003, USA
600
ml1 Introduction

20

sys

6
Auger 2017 preliminary

TA SD, QGSJET II-03
TA hybrid, QGSJET II-03

4 Fe

80

Energy: 8.8 ± 0.5 EeV 859
oZenith: 34.7 ± 0.4
60
Xmax: 697 ± 7 g/cm2/PRELIMINARY/

5<ln A>σ(X*max ) [g/cm2]

RESULTS〈X*max 〉 [g/cm2]

Results comparison: TA SD (MVA) vs TA hyb

Data
QII−04 p
574
359
QII−04 Fe
242
2
χ /d.o.f. (p): 0.75
χ2/d.o.f. (Fe): 0.76

3 Si

dE/dX [PeV/g/cm2]〈lnA〉

dE/dX [PeV/g/cm2]〈lnA〉

dE/dX [PeV/g/cm2]

N
The ground-level muonic component of ultra-high energy
550
2
111
(UHE)
air
showers
sensitive
to hadronic
particlehadronicinterac574leading,15
bservatory areused859
toistest
the
LHC-tuned,
47
35
359
111
242 and
tions
at
all
stagesintheair
showercascade,tomany
35
cted hybrid events collected at the Auger Observatory with47
40
1 He
properties500
of hadronic interactions such as the multiplicity,
matching longitudinal profile have been produced usingelasticity, fraction of secondary pions which are neutral, and1018-07-2017
and Fe primaries. The ground signals of simulated events
the baryon-to-pion
ratio [1]. Air shower simulations rely
0 p
20
450
dupon
muons
relativeevent
to observed
showers,
dependingwhichhadronic
generators(HEGs),
such as on
QGSJETe II
composition
is chosen
to reproduce
the observed
Xmax
Interpretationoftheresults
of
Δ
:
lnA
5
s
[2], EPOS mix[3], andSIBYLL[4]. The HEGs
are tunedon0d.accelerator
The analysis
allows for abutpossibleoverallrescalingof the
400
19
19
19
20
experiments,
when
appliedtoairshowers
18
18.5
19
19.5
20
19
19
19
20
2
×
10
3
×
10
4
×
10
10
2×10 to energies
3×10inaccessible
4×10 to accel10
ncertainties.
they must be extrapolatedE[eV]values obtained with Δs follow the same
logtrendThe
as the results
0 [eV]
10 E, eVE
erators and to phase-space regions not well-covered by ex0
200
400
600
800
1000 1200
measured with the FD. But they are clearly shiftedµergy
cosmicrays,
muons,
hadronic
interactions
experiments.
extrapolations
2
a isting
givenaccelerator
mass, thepredictedThesevalue
of X max result
strongly depends on the hadronic
QGSJetII-04
EPOS-LHC
Depth [g/cm ]in a large
spread in the predictions of the various HEGs foractionmodel• The fluctuations do not depend on the hadronic model.
Xmax ICRC 2015
Xmax ICRC 2015
the muon production in air showers [5].
55EPOS-LHC
data Auger
not compatible
withexpectations∆s 1500 m array∆s 1500 m array
The
Observatory,
com20hybrid nature of the Pierre
Data
Data
Energy: 8.8 ± 0.5 EeV∆s 750 m array∆s 750 m array[TA]
W.Hanlon,
UHECR’16,
also the talk [64QII−04 p
QII−04psurface debining bothZenith:
fluorescencetelescopes
(FD)
[6]
and
o
Conclusive
statements
onmasscomposition
can
not
be
drawn
34.7 ± 0.4
Fe
Fe
4
4
QII−04 FeFe
2 an ideal QII−04
tector arrayX(SD)[7],
providesexperimental
setup
2
max: 697 ± 7 g/cmdata at the χlimitof(p):
compatibility
with100
predictions for iron
QGSJetII-04/d.o.f.
0.75
15
for testing and constraining models of high-energy
hadronic
χ2/d.o.f. (Fe): 0.76
interactions. Thousands of air showers have been collected
Manuela Mallamaci for the Pierre Auger Collaboration, ICRC2017
9
3
3
8
amaci
for
the
PierreAuger
Collaboration,
ICRC2017
which10have a reconstructed energy estimator in both theNN
SD and FD. The measurement of the longitudinal profile
1022(LP) constrains the shower development and thus the signal
predicted
5 for the SD, at the individual event level.
He
He
1

2

Productionof Simulated Events
0
0

200

400

600

800

1000

1200

1
500

1000

1500

2000

2

]

In the present study, we compare the observed
ground signal
2
Depth [g/cm2]
Depth
[g/cm
]
of individual hybrid events to the ground signal of simulated
showers with matching LPs.
Figure 1: Top: The measured longitudinal profile of a
The data we use for this study are the 411Data
hybrid events
typical air shower with two of its matching simulated
18.8
19.2
with 10< E < 10eV recorded between
QII−04 p 1 January
air showers, for a proton and an iron primary, simulated
QII−04Fe
M. andMallamaci,
P. Sanchez-Lucas,
M. Unger,Y. Zhezher
in ICRC2017
2004
31 December 2012and satisfying the event quality
using QGSJET-II-04.
Bottom:The observed
and simulated
100

1

QGSJetII-04 p

0
1017

1018

1019
E [eV]

1020

EPOS-LHC p

0
1017

1018

1019

1020

E [eV]

No perfect models at the highest energies...51
Our result confirms the tension between the hadronic interaction
models and the data in a energy range extending from 1017.5 eV up toAnisotropy: hot/warm spots
All Sky Survey with TA&PAO

Nearby Galaxy Clusters

Oversampling with 20°-radius circle

Ursa Major Cluster(D=20Mpc)
Virgo Cluster(D=20Mpc)

Perseus-PiscesSupercluster(D=70Mpc)

Eridanus
Cluster(D=30Mpc)
Centaurus
Supercluster (D=60Mpc)

No correction for
E scale difference
b/w TA and PAO !!

Northern TA : 7 years 109 events (>57EeV)
Southern Auger : 10 years 157 events (>57EeV)
Southern hotspot is seen at Cen A(Pre-trial ~3.6σ)

Fornax Cluster(D=20Mpc)

Huchra, et al, ApJ, (2012)
Dots : 2MASS catalog Heliocentric velocity <3000 km/s (D<~45MpC)

TA hotspot is found near the Ursa Major Cluster
TA & PAO found no excess in the direction of Virgo.
13

12

K. Kawata in ICRC 2015

Lack of UHECRs from Virgo cluster.

52

TA hotspot update

With%original%20°%oversampling,%spot%looks%
larger….%Thus,%scan%over%15°,%20°,%25°,%30°,%&%35°%

J. Matthews in ICRC 2017With%%25°%oversampling,%signiﬁcance%
maximum%3σ"53

2 doublets above 100 EeV
Small-scale anisotropy

Autocorrelations

Doublet('T=1.31o)

TA 9 years (23 events)

Triplet? orDoublet('T=1.35o)

Auger 6 years (6 events)

2 doublets above 100 EeV.
Æ the probability to have 2 doublets at deg is

P = 0.30% (2.8V)
S. Troitsky in ICRC 201754

Search for Intermediate-scale UHECR Anisotropies
Active Galactic Nuclei

Starburst galaxies - E > 39 EeV
24

22

18

Star-forming of Starburst Galaxies

Likelihood ratio analysis• smearing angle

14
12

12

10

10

8

8

6

6

4
2
0.1
0.15
Anisotropic Fraction

0.2

22

0

14

20
12

o

]

18
16

10

14

8

12
6

10
8

4

6

2

4
0

• H0 : isotropy• H1 : (1 f )⇥ isotropy + f ⇥ fluxMap( )M. Unger in ICRC 2017

0.05

Active galactic nuclei - E > 60 EeV

Search Radius [• 23 objects within 250 Mpc

140(> 1.54, GHz) > 0.3 Jy• flux proxy:16

4• Fermi-LAT search list
(Ackermann+2016) 2012

1.4 GHz(> 1.54, GHz)

16

TS = 2∆ ln L

• 17 objects within 250 Mpc

•

18

]
o

(> 50 GeV)

Search Radius [• flux proxy:20

TS = 2∆ ln L

• 2FHL AGNs

22

20

0.05

0.1
0.15
Anisotropic Fraction

0.2• TS = 2 log(H1 /H0 )0[20 of 30]

55

Search forIntermediate-scale
UHECR
Anisotropies
Pierre Auger Observatory 2017
25

Test statistics

preliminary

Populations
Starburst galaxies
Active galactic nuclei
Swift -BAT

10 5

10 4

15

10 3

10

10 2

5

pre-trial p value

20

Composition scenarios
A
No attenuation

10 6

10 1

0
30

starburst

40
50
Threshold energy [EeV]

f = 10%, = 13⇤
6
pre-trial p-value: 4 ⇥ 10⇤⇤
5
post-trial p-value: 4 ⇥ 10
post-trial⇤⇤ significance: 3.9⇤

incl. f and

60

70

80

AGN

f = 7%, = 7
pre-trial⇤ p-value: 5 ⇥ 10 4
post-trial⇤⇤ p-value: 3 ⇥ 10 3⇤⇤
post-trial significance: 2.7

fit ⇤⇤ penalization for energy scan only. Ncat = 3, previous searches and hidden trials not accounted for.

5514 events above 20 EeV
820 events above 40 EeV[21 of 30]

56

Search for Intermediate-scale UHECR Anisotropies

preliminary

Galactic
coordinate

starburst
f = 10%, = 13⇤
6
pre-trial p-value: 4 ⇥ 10
post-trial⇤⇤ p-value: 4 ⇥ 10 5⇤⇤
post-trial significance: 3.9⇤

incl. f andAGN
f = 7%, = 7⇤
4
pre-trial p-value: 5 ⇥ 10⇤⇤3
post-trial p-value: 3 ⇥ 10⇤⇤
post-trial significance: 2.7

fit ⇤⇤ penalization for energy scan only. Ncat = 3, previous searches and hidden trials not accounted for.

[21 of 30]

57

NORMALIZED RATE

Observation of dipole above 8 EeV

Compatible with dipolar distribution

Observation of Dipolar anisotropy above 8 EeVFirst Harmonic
Harmonic analysis in right ascension ↵(χ2/dof = 10.5/10)

E [EeV] events amplitude r phase [deg.]
P ( r)+0.006
4-8
81701
0.005
80 ± 60
0.60
FLUX MAP ABOVE 8 EeV +0.008
0.002>832187 0.047 0.007
100 ± 10
2.6 ⇥ 10 8Equatorial coordinatessignificant modulation at 5.2 (5.6 before penalization for energy bins explored)
90

Normalized Rate

lue vs exposure

8

1.1
1.08
1.06
1.04
1.02
1
0.98
0.96
0.94
0.92
0.9
360

360

data E>8 EeV
first harmonic300

240 180 120
60
Right Ascension [deg]0-90

3-d dipole above 8 EeV:

0.38

0.42
-180
2 EeV

2MRS

Galactic center

5 EeV) = (100 , 24 )

0.46

+1.3
(6.5 0.9 )% at (↵,km-2 sr-1 yr-1

O. Taborda, M. Unger in ICRC 2017-90

Indicative of an extragalactic origin.
90

E > 8 EeV58

Average Xmax and Xmax -fluctuatio

Auger and TA Surface Detector
SpectraUHECR Astronomy?
Isotropic (E < 8 EeV)

850

~10%

90
Auger FD ICRC17 (prel.) ± stat.
Auger SD ICRC17 (prel.) ± stat± sys.

70

σ(Xmax) [g/cm2]〈Xmax〉 [g/cm2]

800

80

750

700

650

18

10

~10% energy scale difference around ankle region All Sky Survey with TA&PAO•

Systematic uncertainties, reconstruction biases?

•

Anisotropies?

30

19

E [eV]

20

10

10

0

1017

Small-scale anisotropy

Equatorial coordinates

Large discrepancy in shape at E > ~1019.4 eV

40

10
1017

Oversampling with 20°-radius circle

50

20

600

FLUX
MAP
EeV
Ankle
at ABOVE~3 EeV,8 cutoff
at ~40 to 60 EeV

60

Doubletlines: air shower simulations
using post-LHC ha('T=1.31 )o

6

TA 9 yTriplet? orDoublet('T=1.35o)

Galactic centerNorthern TA : 7 years 109 events (>57EeV)

Auger 659

Physics Goal of UHECR Astrophysics

Auger and TA Surface Detec
Spectra~10%

Origin and Nature of Ultra-High Energy
Average X
Cosmic Rays (UHECRs) and Particle
Interactions at the Highest Energies•

Auger FD ICRC17 (prel.) ± stat.
~10% energy scaledifference
aroundAuger
SD ICRC17 (prel.)± stat ankle region± sys.
800

Large discrepancy in shape at E > ~1019.4 eV••

How frequent?: Energy spectrum

Systematic uncertainties, reconstruction biases?

6

Anisotropies?
700
650

What kind of particle?: Mass composition
Where come from?: Arrival direction

750

2

•

Ankle at850~3 EeV, cutoff at ~40 to 60 EeV〈Xmax〉 [g/cm2]•

max and Xmax -fluc

600
1018

1017

FLUX MAP ABOVE 8 EeV
Equatorial coordinates

E [eV]1019

1020

All Sky Survey with TA&PAO

lines: air shower simulations using pos
Oversampling with 20°-radius circle

Galactic centerNo correction for
E scale difference
b/w TA and PAO !!
9

Northern TA : 7 years 109 events (>57EeV)
Southern Auger : 10 years 157 events (>57EeV)

60Southern hotspot is seen at Cen A(Pre-trial ~3.6σ)
12Recent Results and New Puzzle
19.5
Precise observation of the flux suppression above 10 eV, discrepancy

on suppression energy in TA/Auger.

Gradually increase heavier composition above the ankle.
19.7
lighter composition above 10 eV?

Hot/warmspots, correlation with nearby star burst galaxy.
Flux suppression due to GZK process or maximum energy ofaccelerator?
Heavier composition or problem of hadron interaction model? proton
19.7
fraction, mass composition above 10 eV?
Anisotropy as indication of additional light component?
Particle physics extrapolation at the highest energies?

61

- Unpack and final assembly to the frame.

Transport
On-going
upgrade:TA×4
Wave length shifting fiber- If condition is fine, remaining 90 SDs will beshipped quickly.

~200 kg /1SD

Detailed measurement on Hotspot
Enlarge the fourfold coverage to TA×4 = Auger,
arrival to TA site is middle of Mar.
3000 km2 2 clusters- Expectedin the hotspot

Stackable flame up to 10-12 SDs- First 12 TAx4
SDs haveshipped- TAx4 uses WLSFiber , Kuraray Y-11(200).
(D=1.2mm
L=6.1mλatt ~3.7m )from Japan on last Monday
same as TA except length of a fiber- Fiber layout and number are changed to reduce assembly time and cost.

TA SD- Unpack TAx4
and final
SD assembly to the frame.

in the summer of 2020

- If condition is fine, remaining 90 SDs will beshipped quickly.
~2400 kg /stack

Stackable flame up to 10-12 SDs

UHEAP 2016 @ University of Chicago

18

6.1 m fiber
Spacing 4cm
1 fiber route on scintillator 2 time.

5 m fiber
Spacing 2cm

Expected in 2020
(Simulation)– Non uniformity is smaller than < 15% at measurement with test assembly.
– Less number of fiber to assemble gives shorter assemble time.
~2400 kg /stack– Total length of fiber is < ~1/3 . It gives cost reduction.
R&D by K.Saito (ICRR)
UHEAP 2016 @ University of Chicago

E. Kido in ICRC 2017

UHEAP 2016 @ University of Chicago

18

11

62

On-going upgrade: AugerPrime
Scintillator detector

2
Install 4 m Scintillator to measure the mass composition by SD.
SunroofFibers routing

PMT/SiPM

Support
frame
µ
N max

vs Xmax

8.6 QGSJet II.04

p QGSjetII.04
19

E = 5·10 eV
He QGSjetII.04

8.5µ

lg (N )

log10(Nµmax)

Fe

N QGSjetII.04

8

600

p
700

800
Xmax [g/cm2]

Improve electromagnetic/muon separation of SD to measure theAlu 19.7
enclosure
Extruded
scintillator
bars
mass composition above 10 eV.
Boost in statistics by a factor of ~ 10 compared to FD Xmax
Supportanalysis.
frame

He
8.4

WLS fibers(1600 x 50 x 10 mm)

Fe QGSjetII.04

N

Sunroof

Small PMT in the water tank, FD operation during moon night.
900

1000

Xmax (g/cm2)
Unger
R. Smida
in ICRC2017
MuonsM.
may
even
outperform
Xmax

19.7
Origin of flux suppression, proton contribution above 10 eV,
Radomír Šmída – AugerPrime

new particle physics beyond the human-made accelerator.

8

63

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#+" -#)$*$13,)6"0

M. Casolino, A. Olinto in ICRC 2017  
64

Physics goal and future perspectives
Origin and Nature of Ultra-high Energy Cosmic Rays (UHECRs) andParticle Interactions at the Highest Energies
5 - 10 years
Detector
R&D
Exposure and full sky coverage
Radio, SiPM,
TA×4 + Auger
Low-cost
K-EUSO : pioneer detection from
Fluorescencespace and sizable increase of exposure Detector (FD)

“Precision” measurements
AugerPrime
Low energy enhancement(Auger infill+HEAT+AMIGA,
TALE+TA-muon+NICHE)

10 - 20 years
Next-generation observatories
In space (100×exposure): POEMMA, Super-EUSO
Ground (10×exposure with high quality events):65

Fluorescence detector Array of Single-pixel Telescopes✦ Target : > 1019.5 eV, ultra-high energy cosmic rays (UHECR) and neutral particles✦ Huge target volume ⇒ Fluorescence detector arrayFine pixelated camera

Too expensive to cover a huge area

Segmented mirror telescope
Variable angles of elevation – steps.

Single or few pixels and smaller optics
15 deg45 degLow-cost and simplified/optimized FD

66

Fluorescence detector Array of Single-pixel Telescopes✦ Each telescope: 4 PMTs, 30°×30°

20 km

field of view (FoV).

UHECRs✦ Reference design: 1 m2 aperture,

15°×15° FoV per PMT✦ Each station: 12 telescopes, 48 PMTs,
Photons at diaphragm

30°×360° FoV.
1

3

1

✦ Deploy on a triangle grid with 20 km

spacing, like “Surface Detector
Array”.

2

3

Photons at diaphragm

Photons at diaphragm

56 EeV✦ If 500 stations are installed, a groundzenith 500
22coverage is ~ 150,000 km .

✦ Geometry: Radio, SD, coincidence of
16

three stations being investigated.

67

FAST Expected Exposure
1.E+8✦ Conventional operation of FD

under 10~15% duty cycle

Exposures (L=km^2*sr*yr)

1.E+7

FAST

1.E+6

✦ Observation in moon night to

JEM-EUSO
tilt

achieve 30% duty cycle,

JEM-EUSO
nadir

1.E+5
Auger

✦ Target: >1019.8 eV = SuperGZK events

TAx4

TA

1.E+4

✦ Target: >1019.5 eV✦ Test operation by Auger FD

HiRes✦ Ground area of 150,000 km2 with

AGASA

1.E+3

Preliminary

Fly's Eye

1.E+2
1990

2000

2010

2020
Year

2030

2040

30% duty cycle = 45,000 km2(15×Auger, cost ~100 Million USD)

✦ 450 events/year68

FAST - today

Full-scale FAST Prototype✦ Confirmed milestones by EUSO-TA Telescope✦ Stable operation under high night sky backgrounds.

Vertical Laser~1019.3 eV✦ UHECR detection.
Accepted for publication✦ T. Fujii et al., Astropart.Phys. 74 (2016) 64-72,

arXiv: 1504.00692

in Astroparticle Physics✦ Next milestones by new full-scale FAST prototype

Cosmic ray~1018.0 eV✦ Establish the FAST sensitivity.
✦ Detect a shower profile including Xmax with FAST

69

70

Full scale FAST prototype

FAST - progress in design and construction
Prototype - October 2015
1m2 aperture
FOV = 25°x 25°
15°

variabletilt

UVband-passPlexiglass
UV
filter8 inch PMT camera(2 x 2)

Segmented primary mirror

45°

71

60

20-pin base, and have a HV
ch of the PMTs is prefixed
Department of Physics, University of Chicago
PMT number. We test theby obtaining a single photoPMT ZS0018
Single photo electron
asurement. We place a single
output of the dual-channel
front of the PMT. The LED
00 kHz; typical LED ampli1.5 V and ⇡ 100 ns.
he PMT is connected to theamplifier; the two resulting
to the FADC input and first
espectively. The PMT anode
FADC converts the signal toof 0 to 4095 (12-bit range).

100
40

PMT Calibration

20

40

50
20

10

20

2000

4000

6000

00
−200
−100
0 800010000
100 12000200−2000
0 20004000 6000
14000
16000

8000 10000 12000

1200

1000

23504

Mean

2111

RMS

2691

r2 / ndf

175.6 / 85

Constant

184.8 ± 2.3

Mean4582 ± 30.6

Sigma

1933 ± 21.9

800

600

Np.e. / (100 ns)

40
30
20

20
10

200

-10

0

5000

10000

15000

20000

25000

Mean
22. Mean
HV = 2252V, Disc = 50mV, x20 Amp
RMS
RMS

1000
r2 /=ndf
2 =18 24. r
HV
85mV, x20 Amp/ 2266V,
ndf Disc
140

16

120
800

14

43157
23504
4210
0.857
6062
55.09
263.4
/ 104
0 / −3161.5± 2.1
Constant Constant
184.8
± 1.4
Mean
9949
± 34.525. Mean
HV = 2000V, Disc= 44mV, x20 Amp 4582
± 1.4
Sigma

Sigma

250

Constant
Mean2982± 42.91933 ±
8350.8

Sigma
200

100

12

600
80
10

150

8

60
400

100

6
40

4

200
20

50

2

00
0 −1502000
0 100
5000−50
10000
−200
−100

400
15000
20000
25000
50300100150

500

Integrated
countsIntegrated
counts0600 −200 700−100
Wavelength [nm]YAP pulser (YAlO3:Ce
UV
LEDresults
illuminating
FIG. 13. Detection
efficiency
with Hamamatsu mscintillator + 241Am source)surement for comparison.
the front of the camera
FIG. 7.
Integrated
distribution of SPE signals, includattachedon eachcount
PMT surface
PMT ZS0024

PMT ZS0025

300

400

500

600

700

800

0

30
20
10

200

300

400

500

600

700

800

Time (100 ns)

PMT 1

1000

1000

300

800
600

400

200

200

0

0

100 200 300 400 500 600 700 800
Time (100 ns)
PMT 2

100

200

300

0

PMT 4

1000

800
600

800
600

400

400

200

200

0

0

0

100 200 300 400 500 600 700 800
Time (100 ns)

1200

1000

-20

600

400

1200

-10

800

maining lights in the lab are switched o↵. The compuin the lab is accessed remotely to begin data acqu200
tion. The DAQ program controls the monochroma
150
After specifying
the signalandregionforIttheaveraged
SPEre
powermeter.
obtains
and averages 10,000
100
ings from the powermeter
10 s for a given step;
FIG. 12. SPE
peak height
distribution
used toaset SPE
discrimi- integrated
signal,we
obtaincountoverdistribution,
50
nator threshold value. The pedestal ends at around a heighterror, P , is calculated in quadrature from Poisson sta
0
asrangea charge
distribution. Since someof 350 ADCsometimes
counts. Dividing thisdisplayedby the 4095 dynamic
tics on both powermeter readings, lamp signal and ba
72
400 the
500 FADC
600 events
700
0
100
200
300 no400 ⇡ 500
600
700
800
of
gives800a discriminator
threshold
of
85
mV.
will
have
photoelectrons(i.e.
nocharge),weground. The lamp background corresponds to when
250

Np.e. / (100 ns)

Time (2 ns)

0

1200

1200

0

1400

PMT 3

ing pedestal (left PMTpeak)and SPE peak fitted to a Gaussian
4
for all PMTs.
the powermeter and monochromator initialized, any
Np.e. / (100 ns)

PMT 2

100

Np.e. / (100 ns)

200

Np.e. / (100 ns)

100

Time (100 ns)-30
0

r2 / ndf

-40

-40
0

used in AIRFLY experiment
Astropart.Phys. 42 (2013)
90–102

Hamamatsu (Scaled)
PMT ZS0025
Entries
PMT ZS0024
PMT
300ZS0022 Mean
PMT ZS0018 RMS

-30

-30

Np.e. / (100 ns)

0

-20

-20

1200

20

Entries

Integrated counts

-10

1000

160

400

0

10

800

PMT 3

Entries

Np.e. / (100 ns)

Np.e. / (100 ns)

PMT 1

−100

Integrated
countsIntegrated
counts1200
22 18. HV = 2169V, Disc = 38mV, x20 Amp

Entries

1400

Entries−200

PMT ZS0022
Detection
Efficiency: FAST PMTs

Entries[%]
Efficiency

Entries

Integrated counts

0

Entries0

100 200 300 400 500 600 700 800
Time (100 ns)

0100 200 300 400 500 600 700 800
Time (100 ns)

Telescope alignment and raytracing simulation
Mirror alignment by 2 LED

Telescope alignment with stars

focalOpticalplane
simulation 50
status mm offset!

FAST Simulation - example

Raytracing simulation for spot
Mirror reflectance and filter transmittance- PSF (7.5deg diagonal) aperture input 0.5W 0.43W/PMT1, <0.001W/PMT234 (eff: 86%)100
sizes and angular responses
90
70
60
50

PMT2!

40
30

Mirror reflectivity

20

Filter transmission

10

Total efficiency

0
260

280

300

320 340 360 380
Wavelength [nm]

400

420

2017 J

Efficiency [%]80

information
recently
published
D.withMandatet al., JINST 12, T07001 (2017)
ure 5.Further
The typical spectralreflectance of in
the FAST
mirror between
260 nm andpaper,
420 nm, along
the

PMT4!

73

Distant vertical laser comparison in Data/MC✦ Ultraviolet vertical laser at a distance of 20.85 km, E = 4.4

30
20
10
0

20
10

✦ Every 30 minutes during a clear night, equivalent to a

-20

-30

-30
0

100 200 300 400 500 600 700 800
Time (100 ns)
PMT 2

30
20
10

Np.e. / (100 ns)

Np.e. / (100 ns)

30

-10

-20

100 200 300 400 500 600 700 800
Time (100 ns)

40✦ Calculate expected signal by simulation and good30
20

agreement with observed data.

0

-10

-10

-20
100 200 300 400 500 600 700 800
Time (100 ns)-20
0100 200 300 400 500 600 700 800
Time (100 ns)

Np.e. / (100 ns)

Average of 284 triggers
20
15

PMT 1
PMT 2
PMT 3
PMT 4

10

✦ Monitoring the transparency of the atmosphere.
25

Simulation (Preliminary)
PMT1

20

PMT2

15

PMT3
PMT4

10

5

5

0
0

UHECR with ~1019.5 eV

PMT 4

10

0

0

mJ, λ = 355 nm,

PMT 3

0

-10

0

40

Np.e. / (100 ns)

PMT 1

40

Np.e. / (100 ns)

Np.e. / (100 ns)

Single event

100 200 300 400 500 600 700 800
Time (100 ns)

00

100 200 300 400 500 600 700 800

74PMT 3

Np.e. / (100 ns)

Np.e. / (100 ns)

PMT 1
100

Event search
80
60

40
30
20
10

40

0

20

-10

0

-20

-20

0

100

200

300

400

500

600

700

-30
0

800

100

200

300

400

500

600

Time (100 ns)

800

PMT 4

Np.e. / (100 ns)

PMT 2

Np.e. / (100 ns)✦ Data on Oct.5th 2016

All triggers

Airplane

700

Time (100 ns)

140
120
100

40
30
20

80
60

10

40

0

20
-10

0
-20

✦ 62194 triggers

0

-20
100

200

300

400

500

600

700

800

Time (100 ns)

0

100

200

300

400

500

600

700

800

Time (100 ns)

Laser✦ PMT1,2,3,4✦ Circle size = significance✦ Remove airplane (>35 µs) andlaser events (time information).

Selected triggers✦ Two significant signal in PMTs
✦ 90 events survived✦ 2 events found as candidates.
✦ Check TAFD reconstruction

result.
75

First lights from UHECREvent 387: log10 (E(eV)): 18.68, Zen: 61.0 , Azi: 63.3◦ ,Core(11.86, -11.50), Rp: 3.52, Psi: 42.8◦ , Xmax: 1113 g/cm2
FoV(1407 - 1769), Date: 20161005, Time: 06:07:38.800548560

Event 393: log10 (E(eV)): 18.14, Zen: 31.6◦ , Azi: 2.8◦ ,Core(6.02, -6.69), Rp: 11.96, Psi: 102.1◦ , Xmax: 762 g/cm2
FoV(373 - 991), Date: 20161005, Time: 06:51:48.292842002① 2016/10/05 06:37:49.525424540
PMT 3

60

40

40
30
20

20

PMT 3

PMT 1

Np.e. / (100 ns)

Np.e. / (100 ns)

PMT 1

Np.e. / (100 ns)② 2016/10/05 10:25:50.781802380
Np.e. / (100 ns)

◦

2000

1500

300
250
200

10

0

150

1000

0

100

500
Event-20 388: log10 (E(eV)): 17.96, Zen: 38.8-10◦ , Azi: -19.6◦ , Event 394: log10 (E(eV)):
18.69, Zen: 61.2◦ , Azi: -9.4◦ ,-20-40
Core(8.90,-17.03), Rp: 9.44, Psi: 82.6◦ , Xmax:
768 g/cm2 Core(9.58, -20.15), Rp: 0 9.27, Psi: 57.3◦ , Xmax: 1021 g/cm2
0
200
300
400
500
600
700
800
0
100
200
300
400
500
600
800
0
100
200 Time:
300
400 06:53:27.011365323
500
600
700
800
FoV(498-1001017),
Date:
20161005,
Time:
06:30:06.947113522
FoV(829-7001221),
Date: 20161005,
Time (100 ns)

PMT 4

Np.e. / (100 ns)

40
30
20

40
30
20

10

10

0

0

-10

0
0

100

200

300

400

500

600

700

800

Time (100 ns)

PMT 2

Np.e. / (100 ns)

PMT 2
50

50

Time (100 ns)

PMT 4

Np.e. / (100 ns)

Time (100 ns)

Np.e. / (100 ns)

350

1000

800

300
250
200

600

150

400

100

200

50

-10

-20

◦
Event-30 389: log10 (E(eV)): 17.83, Zen: 4.7-20, Azi: 115.2◦ , Event 395: log10 (E(eV)): 18.26, Zen: 17.7◦ , Azi: -82.0◦ ,
0
-30
◦
2
◦
2
-40
Core(14.23,
7.18,
86.7
, Xmax:656200 g/cm
-2.14),
Rp: 0 10.39,
Psi:
98.2
,
Xmax:
769
g/cm
0
100 -5.41),
200
300 Rp:400
500
600 Psi:
700
800
0
100
300
400 Core(13.53,
500
600
700
800
100
200
300
400
500
600
700
800
FoV(473 - 850), Date: 20161005, Time: 06:35:10.462924009
FoV(303 - 890), Date: 20161005, Time: 06:53:43.909532618
Time (100 ns)

Time (100 ns)

TAFD
logE = 18.08
Rp = 2.40 km

Time (100 ns)

0
0

100

200

300

400

500

600

700

800

Time (100 ns)

Too
close
76

Highest UHECR, logE=18.55
Open

Close!

✦ Fully remote operation✦ Monitor a shutter by an infrared camera✦ IP camera (PIC1008WN), relay module (ETH002)✦ Total operation time reaches 201 hours by July.

Np.e. / (100 ns)✦ Automated shutdown procedure

Event 342

PMT 1
200
Event 529: log10 (E(eV)): 17.86, Zen: 52.0◦ ,PMT
Azi:2 -81.0◦
2
Core(19.25, 150-7.29), Rp: 5.12, Psi: 77.2◦ , Xmax:
569
g/cm
PMT 3
FoV(780 - 1102), Date: 20161007, Time: 05:38:07.968860386
PMT 4
100

50
0
0

100 200 300 400 500 600 700 800
Time
(100
ns)
Event 530: log10 (E(eV)): 18.33, Zen: 64.1◦ , Azi: 159.6◦
2
18.5528.5
Core(15.32,-9.36),
Rp: 1.51,
1264
g/cm
Highestevent,
E=10Psi:eV,◦ , RXmax:
=3.0
km
p
FoV(1795- 1972),by TA
FDDate: 20161007, Time: 05:38:31.715231263

18 events found by January (120 hours)

77Auger and TA Surface Dete
Possible Application of FASTSpectra
Prototype✦ Install FAST at Auger and TA for a cross calibration.
~10%

Efficiency

1
Proton✦ Profilereconstruction with geometry given by SD (smearing

gaussian width of 1° in direction, 100 m in core location).
Iron

0.8

88

0.6

✦ Energy: 10%, Xmax : 35 g/cm

at
10
eV
The hybrid detector of the Pierre Auger Observatory [1] consists of 1600

1. Introduction
2
19.5

0.4
0.2

surface stations – water Cherenkov tanks and their associated electronics – and24 air19.6
fluorescence telescopes. The Observatory is located outside the city of
19.4
Malargüe, Argentina (69◦ W, 35◦ S, 1400 m a.s.l.) and the detector layout isshown in Fig. 1. Details of the construction, deployment and maintenance of
the array of surface detectors are described elsewhere [2]. In this paper we willconcentrate on details of the fluorescence detector and its performance.

18
18.2 18.4 18.6cross-check18.8
1919.2 of Energy and Xmax scale✦ Independent0

between Auger and TA

Energy Resolution [%]log(E(eV))

X max Resolution [g/cm2]

T. Abu-Zayyad et al. / Nuclear Instruments and Methods in Physics Research A 689 (2012) 87–97

25

Energy20
15
10

Proton

5
0

18.2

18.4

18.6
18.8
log(E(eV))

19

100

19.2

19.4

19.6

a b s t r a c t

Article history:
Received 25 December 2011
Received in revised form
25 May 2012
Accepted 25 May 2012
Available online 2 June 2012

The Telescope Array (TA) experiment, located in the western desert of Utah, USA,observation of extensive air showers from extremely high energy cosmic rays. The
surface detector array surrounded by three fluorescence detectors to enable simulta
shower particles at ground level and fluorescence photons along the shower trac
detectors and fluorescence detectors started full hybrid observation in March, 2008
describe the design and technical features of the TA surface detector.
& 2012 Elsevier B.V.

Keywords:
Ultra-high energy cosmic rays
Telescope Array experiment
Extensive air shower array

1. Introduction
The main aim of the Telescope Array (TA) experiment [1] is to
explore the origin of ultra high energy cosmic rays (UHECR) using
their energy spectrum, composition and anisotropy. There are two
major methods of observation for detecting cosmic rays in theenergy region above 1017.5 eV. One method which was used at theHigh Resolution Fly’s Eye (HiRes) experiment is to detect air
fluorescence light along air shower track using fluorescence
detectors. The other method, adopted by the AGASA experiment,
is to detect air shower particles at ground level using surface
2
detectors deployed over a wide area ( ! 100 km ).
The AGASA experiment reported that there were 11 events
above 1020 eV in the energy spectrum [2,3]. However, theexistence of the GZK cutoff [4,5] was reported by the HiRes

experiment [6]. The Pierre Auger experimen
suppression on the cosmic ray flux at energy a[7] using an energy scale obtained by fluores
scopes (FD). The contradiction between results f
detectors and those from surface detector arrays
be investigated by having independent ener
both techniques. Hybrid observations with SD
us to compare both energy scales. Information aband impact timing from SD observation impro
reconstruction of FD observations. Observatio
detectors have a nearly 100% duty cycle, which
especially for studies of anisotropy. Correlations
directions of cosmic rays and astronomical objec
region should give a key to exploring the origin otheir propagation in the galactic magnetic field.

•

Ankle at ~3 EeV, cutoff at ~40 to 60 EeV•~10% energy scale difference aroundTelescope
ankle region
Array

•

Iron

18

Pierre Auger Observatory

a r t i c l e i n f o

Identical
Experiment
Large discrepancy in shape at E > ~10
eV
simplified FD
19.4•

Systematic uncertainties, reconstruction biases?

•

Anisotropies?

6

Xmax

80
60
40

Proton

20
0

Iron

18

18.2

18.4

18.6
18.8
log(E(eV))

19

19.2

19.4

19.6

Figure 1: Status of the Pierre Auger Observatory as of March 2009. Gray dots show the
Pierre Auger Collaboration, NIM-A (2010)
positions of surface detector stations, lighter gray shades indicate deployed detectors, while

Fig. 1. Layout of the Telescope Array in Utah, USA. Squares denote 507 SDs. There are three subarrays controlled by three communication towers den
three star symbols denote the FD stations.

Telescope Array Collaboration NIM-A (2012) 78

Spectra

Summary~10%

19.5
Precise observation of the flux suppression above 10 eV,

Average Xmax and Xmax -fluctu

discrepancy on suppression energy in TA/Auger.

A next-generation observatory is essential to clarify
origins of UHECRs.

~10% 800
energy scale± sys. difference around ankle region•

Large discrepancy in shape at E > ~1019.4 eV

80

Auger SD ICRC17 (prel.) ± stat•

750
Systematic
uncertainties, reconstruction biases?

70

6Anisotropies?
700
650

60

50

40

30

20

10

600

FLUX MAP ABOVE 8 EeV
17Equatorial coordinates 18

10

FAST: fluorescence detector array of Single-pixel
Telescopes
Installed full-scale FAST prototype at TA site, anddetects laser and UHECRs.

••

Hot/warm spots, correlation with nearby star burst galaxy.

90

σ(Xmax) [g/cm2]

lighter composition above 1019.7 eV?

•

850
Ankle at ~3 EeV,
cutoff
at ~40
to± 60Auger
FD ICRC17(prel.)
stat.EeV〈Xmax〉 [g/cm2]

Gradually increase heavier composition above the ankle.

19

10

0

20

10
10
All
Sky
Surveywith
TA&PAOE [eV]
Oversampling with 20°-radius circle

lines: air shower simulations using post-LH

Galactic centerNo correction for
E scale difference
b/w TA and PAO !!
9

Northern TA : 7 years 109 events (>57EeV)
Southern Auger : 10 years 157 events (>57EeV)
Southern hotspot is seen at Cen A(Pre-trial ~3.6σ)
12

We will install two more telescopes in September 2017.
New collaborators are welcome.

Future observatories: TA×4, AugerPrime, K-EUSO and FAST

79