Tunka-133: status and results

L.A.Kuzmichev (SINP MSU)

On behalf on the Tunka Collaboration

Moscow, May 2011

S.F.Beregnev, S.N.Epimakhov, N.N. Kalmykov, N.I.KarpovE.E. Korosteleva, V.A. Kozhin, L.A. Kuzmichev, M.I. Panasyuk, E.G.Popova, V.V. Prosin, A.A. Silaev, A.A. Silaev(ju), A.V. Skurikhin, L.G.Sveshnikova I.V. Yashin, – Skobeltsyn Institute of Nucl. Phys. of Moscow State University, Moscow, Russia;

N.M. Budnev, A.V.Diajok , O.A. Chvalaev, O.A. Gress, A.V.Dyachok, E.N.Konstantinov, A.V.Korobchebko, R.R. Mirgazov, L.V. Pan’kov, Yu.A. Semeney, A.V. Zagorodnikov – Institute of Applied Phys. of Irkutsk State University, Irkutsk, Russia;

B.K. Lubsandorzhiev, B.A. Shaibonov(ju) , N.B. Lubsandorzhiev– Institute for Nucl. Res. of Russian Academy of Sciences, Moscow, Russia;

V.S. Ptuskin – IZMIRAN, Troitsk, Moscow Region, Russia;

Ch. Spiering, R. Wischnewski – DESY-Zeuthen, Zeuthen, Germany;

A.Chiavassa– Dip. di Fisica Generale Universita' di Torino and INFN, Torino, Italy.

D. Besson, J. Snyder, M. StockhamDepartment of Physics and Astronomy, University of Kansas, USA

Tunka Collaboration

Search for the Acceleration Limit of Galactic Sources- Energy range 1016-1018 eV demands:- 1 km² with spacing smaller than that at Auger- complementary techniques

IceTop

IceCube

- KASCADE-Grande terminated - IceTop/IceCube in operation- Tunka-133 (calorimetric) in operation- NEVOD-DÉCOR in operation-GAMMA in operation- Auger low energy extension 80% ready- HiSCORE planned-LHAASO planned

V.Ptuskin andV.Zirakashvili,2010

Tunka-133

OUTLINE 1. Non-imaging Air Cherenkov Technique

2. Tunka-133: construction and deployment.

3. Results after first season.

4. Plan for the Tunka-133 upgrading.

5. Future plans.

20-30km

P, A For Ee >25 MeVVe > C/ n – light velocity in air

Cherenkov light

Photons detectors

Q tot N(x) dx ~ E

Atmosphere as a huge calorimeter

E (PeV) = 0.4 Q(175) ph· ev-1 cm-2

LateralDistributionFunction

Advantage of Cherenkov Technique:

1. Good energy resolution - up to 15%2. Good accuracy of Xmax - 20 -25 g/cm2

3. Good angular resolution - 0.1 – 0.3 deg4. Low cost – Tunka-133 – 1 km2 array: 0.5 106 E ( construction and deployment) + 0.2 106 E( PMTs) Cost of 100 km2 array - 107 E

Disadvantage:

1.Small time of operation ( moonless, cloudless nights) – 5-10% 2. Existence of moving lids on modules

Summary of methodic used in Tunka-133

( more detail in V.Prosin report at Wednesday)

1. Energy: E (PeV) = 0.4 Q(175) ph· ev-1 cm-2

From CORSIKA, no dependence from hadronic model

2. Core location: LFD and WDF ( width-distance function) accuracy – 10 m

3. Energy resolution: 15%

4.Xmax - p (steepness from LDF) - τ(400) – time width at 400 m from the core

Tunka-133 – 1 km2 “dense” EAS Cherenkov light array

Energy threshold 1015 eV

Accuracy: core location ~ 10 m energy resolution ~ 15% Xmax < 25 g∙cm-2

Tunka-133: 19 clusters, 7 detectors in each cluster

Optical cableClusterElectronic box

DAQcenter

PMTEMI 9350Ø 20 cm

4 channel FADC boards 200 MHz, 12 bit

Array depoliment Optical cables

Detectors

Testing PMTs

DAQ systemCluster

Local trigger: > 3 hit detectors in 0.5 µs

Optical detector

ClusterElectronicbox

1 Gb Ethernet:Data transmission +Synchronization

Optical detector of Tunka-133

PMTEMI 9350Ø 20 cm

Angular sensitivity

4 channel FADC

1. ADC AD9430, 12 bit, 200 MHz2. FPGA XILINX Spartan-3

Port for FADCconnection(trigger, requests)

Optical transceiver(central DAQconnection

Time synchronization chain

Accuracy of time synchronization 10 ns

Two seasons of array operation

2009 - 2010 :286 hours of good weather . 2010 – 2011: 270 hours of good weather. 4106 events with energy 1015 эВ.

Trigger counting rate during one night .

Distribution of the number of hitted clusters in one event.

50 detectors 1016 eV

10 events during every night with number of hitted detectors more than 100.

Experiment:Every event = 3 – 133 pair pulses:

Reconstruction of parameters:1) Delay at the level 0.25Amax, 2) the full area under pulse, 3) FWHM

anode

dynode

ti

FWHM

11th cluster 19th cluster 500 m

EAS zenith angular distribution (E0>1016 eV)

Energy spectrum (from first season data)

Core position insidecircle: R = 450 mZenith angle < 45°

All: 1 117 907

>1016 eV : 18714> 1017 eV: 202

Example of event Energy: 2.01017 eV zenith angle : 12.6 °

125 detectors

R lg ( I light )

Core position:

LDF -method

WDF -method

.A– Fitting experimental points with LDF

B – Fitting of ( R) with Width – Distance Function.

A B

Thershold

Lg Qexp (R )

LDF

WDF

Lg (R )

Events with largest energy – near to 1019 eV – was found out with the help of radio antenna

353 events

277

Good pointing for the existing of “ bump”

4.2 December 2010

373

293

4.2

MAY 2011

Specter with 2 types of sources Eknee =4 PeV (0.75)+4x150 PeV (0.25

104 105 106 107 108 109 1010 1011 1012104

105

106

107

108

3.38E6

Pure Galactic

0.20

E2knee=4x150

Sum Gal+Metag 025

F(E

) E3.

0

E, GeV

Tun133 GrandeKas Hires1 Hires2 EASTOP Tibet KASKADE Tunka25 MGUIE3 AKENO Augergv Hires1M3 All z1 z2 z6 z8 z10 z14 z16 z18 z20 z26 tot B tot

Specter with 2 types of sources Eknee =4 PeV (0.75)+4x150 PeV (0.25)

Here we need to knowMeta-Galactic

PHe

C,O

Fe

Si

Total all –particle spectrum in our model

Galactic sources

Mass composition: 3 dif. variants

• 1) Emax (P)

• In Galaxy ; 4 PeV

• 2) Emax (P)=4 and

• 600 PeV

• This variant predicts a heavy composition at 1018 eV

• 3) SNR Ia + He stars +MetaGalactic with mixed composition in sources

Plan for Tunka-133 upgrading

- Far distant clusters for increasing effective area

- Net of radioantennas

- Low threshold array

- Scintillation muon counters

E0 , Xmax ( from Tunka-133 ), Nµ

1 km

.6 additionalclusters( 42 detectors)

IncreasingEffectiveArea in 4 timesfor energymore than1017 eV In operation

Statistics in 2012 ( > 1017 eV) : 600 (inner events) +600 (out events) All: 1200 events

Registration of radio signals from EAS

Antennas are connected to the free FADC

channels of Tunka-133 cluster electronics

Choosing the type of antennas:Now 2 types of antennas were

installed at Tunka Array

Log-periodic antenna (D. Besson et al. University of Kansas, USA)

Short Aperiodic Loaded LoopAntenna (SALLA)(A.Haungs et al. Institute furKernphysick, Forschungszentrum,Karslruhe, Germany

6 antennas

2 antennas

Nearly 100 candidates

SCORE project – wide-angle gamma-telescope with area 10 -100 km2 and threshold 30 тэВ(M.Tluczykont et al , ArXiv: 0909.0445)

SCORE: Study for Cosmic ORigin Explorer

Time schedule 1.First SCORE Station will be installed at Tunkain this summer-autumn2.20 station at 2012 – 1 sq. km telescope ( good chance)3. ??

Energy spectrum from 1014 - 1017 eV - compare with Tunka-25 and Tunka-133 results

Muon detectores

lgNµ (corr)= lgNµ -

1500

Xmax - 600

S = 5 m2

40 muon detectors on the area of 1km2

766 г/см2

675 г/см2

Search for diffuse gamma radiation at high energy

Future plan: 100 km2 array

1. Spacing between detectors – 250 m2. Cluster principle of organization: 8-10 detector in one cluster3. PMT - with 20 cm diameter photocathode 4. Energy threshold (3-5) 1016 eV 5. Digitization of signals in optical detectors 6. Optical cables for data transmission and synchronization

PMT - 1500 -2000 piecesCable – 1000 km

Total price - 107 Eu

Time schedule 1. Proposal to the end of 2012 2. When - ?3. Where ?? May be with Auger-Next

Conclusion 1.The spectrum from 1016 to 1017 eV cannot be fitted with one power law index g : 3.2 to 3.0 at 2 1016 eV.

2. Very good agreement with KASKADE-Grande results ( up to 71016 ).

3. For energy > 1017 eV we need much more statistics.

4. “Bump” at 8.1016 eV - possible indication of a bump + agreement with GAMMA. But not seen by KASKADE-Grande.

5. Indication on light composition at energy > 1017 eV

6. Update 2011: - Far distant clusters. - Net of radio antennas. - First SCORE detectors.

Thank You