1 tibet air shower array plus muon detector array for the 100 tev gamma-ray wide sky survey k....
TRANSCRIPT
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Tibet Air Shower Arrayplus Muon Detector Array
for the 100 TeV Gamma-RayWide Sky Survey
K. Kawata
For the Tibet AS Collaboration
ICRR, University of Tokyo
Locating PeV Cosmic-Ray Accelerators: Future Detectors in Multi-TeV Gamma-Ray AstronomyAdelaide 6 - 8 December 2006
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M.Amenomori,1 S.Ayabe,2 X.J.Bi,3 D.Chen,4 S.W.Cui,5 Danzengluobu,6 L.K.Ding,3 X.H.Ding, 6
C.F.Feng,7 Zhaoyang Feng,3 Z.Y.Feng,8 X.Y.Gao,9 Q.X.Geng,9 H.W.Guo,6 H.H.He,3 M.He,7 K.Hibino,10
N.Hotta,11 HaibingHu,6 H.B.Hu,3 J.Huang,12 Q.Huang,8 H.Y.Jia,8 F.Kajino,13 K.Kasahara,14Y.Katayose,4
C.Kato,15 K.Kawata,12 Labaciren,6 G.M.Le,16 A.F. Li,7 J.Y.Li,7 Y.-Q. Lou,17 H.Lu,3 S.L.Lu,3 X.R.Meng,6
K.Mizutani,2,18 J.Mu,9 K.Munakata,15 A.Nagai,19 H.Nanjo,1 M.Nishizawa,20 M.Ohnishi,12 I.Ohta,21 H.Onuma,2
T.Ouchi,10 S.Ozawa,12 J.R.Ren,3 T.Saito,22 T.Y.Saito,23 M.Sakata,13 T.K.Sako,12 T.Sasaki,10 M.Shibata,4
A.Shiomi,12 T.Shirai,10 H.Sugimoto,24 M.Takita,12 Y.H.Tan,3 N.Tateyama,10 S.Torii,18 H.Tsuchiya,25
S.Udo,12 B. Wang,9 H.Wang,3 X.Wang,12 Y.G.Wang,7 H.R.Wu,3 L.Xue,7 Y.Yamamoto,13 C.T.Yan,12
X.C.Yang,9 S.Yasue,26 Z.H.Ye,16 G.C.Yu,8 A.F.Yuan,6 T.Yuda,10 H.M.Zhang,3 J.L.Zhang,3 N.J.Zhang,7
X.Y.Zhang,7 Y.Zhang,3 Yi Zhang,3 Zhaxisangzhu,6 and X.X.Zhou 8
(1) Dep. of Phys., Hirosaki Univ., Hirosaki, Japan(2) Dep. of Phys., Saitama Univ., Saitama, Japan(3) Key Lab. of Particle Astrophys., IHEP, CAS, Beijing, China(4) Fac. of Eng., Yokohama National Univ., Yokohama , Japan(5) Dep. of Phys., Hebei Normal Univ., Shijiazhuang, China(6) Dep. of Math. and Phys., Tibet Univ., Lhasa, China(7) Dep. of Phys., Shandong Univ., Jinan, China(8) Inst. of Modern Phys., South West Jiaotong Univ., Chengdu, China(9) Dep. of Phys., Yunnan Univ., Kunming, China(10) Fac. of Eng., Kanagawa Univ, Yokohama, Japan(11) Fac. f of Educ., Utsunomiya Univ., Utsunomiya, Japan(12) ICRR., Univ. of Tokyo, Kashiwa, Japan(13) Dep of Phys., Konan Univ., Kobe, Japan(14) Fac. of Systems Eng., Shibaura Inst. of Tech., Saitama, Japan
(15) Dep. of Phys., Shinshu Univ., Matsumoto, Japan(16) Center of Space Sci. and Application Research, CAS, Beijing, China(17) Phys. Dep. and Tsinghua Center for Astrophys., Tsinghua Univ., Beijing, China (18) Advanced Research Inst. for Sci. and Engin., Waseda Univ., Tokyo, Japan(19) Advanced Media Network Center, Utsunomiya University, Utsunomiya, Japan(20) National Inst. of Info., Tokyo, Japan(21) Tochigi Study Center, Univ. of the Air, Utsunomiya, Japan(22) Tokyo Metropolitan College of Industrial Tech., Tokyo, Japan(23) Max-Planck-Institut fuer Physik, Muenchen, Germany (24) Shonan Inst. of Tech., Fujisawa, Japan(25) RIKEN, Wako, Japan(26) School of General Educ.,Shinshu Univ., Matsumoto, Japan
The Tibet AS Collaboration
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Contents
1. Introduction2. Tibet Air Shower Array Tibet Muon Detector Array3. Sensitivity Simulation4. Outlook5. Costs6. Summary
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1. IntroductionCosmic ray Acceleration Origin
New 14 HESS sources
Hard spectral indices
Faint in other wavelengths
Theoretical
possibility
• 0 decay• IC*• …
• Old SNR• Asymmetric PWN• …
Key observation 100 TeV region Wide sky survey
Aharonian et al, ApJ, 636, 777 (2006)
* >100TeV IC is difficult due to sync. cooling & KN effect
200GeV-10TeV200GeV-10TeVNew 14 HESS sourcesNew 14 HESS sources
SuzakuSuzakuHESS J1616-508HESS J1616-508
Matsumoto et al, PASJ, in pressastro-ph/0608475
Yamazaki et al, MNRA,371, 1975 (2006)
Blondin et al, ApJ,563, 806 (2001)
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2. Tibet Air Shower (AS) Array
Tibet China (90.522oE, 30.102oN) 4300 m a.s.l.
Number of Scinti. Det. 0.5 m2 x 789 Effective Area for AS ~37,000 m2
~50,000 m2
Energy region~TeV - 100 PeV Angular Resolution ~0.4 @10 TeV (Gamma) ~0.2 @100 TeV Energy Resolution ~70% @10 TeV (Gamma) ~40% @100TeV F.O.V. ~2 sr
Tibet Muon Detectors (Image)
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Tibet Muon Detector (MD) Array7.2m x 7.2m x 1.5m depth Water pool20”PMT x 2 (HAMAMATSU R3600)Underground 2.5m ( ~515g/cm2~19X0)
Material: Concrete pool White epoxy resin paint 184 detctors Total 9540 m2
Counting the number of muons accompanying an air shower
Present AS ArrayFuture AS+MD Array (Type 1)Future AS+MD Array (Type 2)
Gamma/Hadron separation
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Milagro SK (Anti) Tibet MD
PMT 8”PMT 8”PMT 20”PMT
Detector Area80m x 60m Depth8m
(Upper4800m2 /Lower2000m2)All Surface ~7400m2
Thickness ~2.5m 9540m2
Depth1.5m
Unit [email protected]×2.8m 2PMTs@6m2 2PMTs@52m2
Photo- Coverage 0.4% 0.52% 0.75%
Number of PMTs
Upper: Depth 1.4m, 450Lower: Depth 6.0m, 273
1885 368
Already established technique High cost performance Easy to design long path length detector Cherenkov threshold (electron 750keV in the water)
Water Cherenkov Technique
High rejection power for low energy e+/- & Good technique for muon detection
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Future AS+MD Array (Type 2)
Air Shower Generation - Corsika Ver.6.204 CR: 0.3TeV-10PeV, Crab Orbit Chemical components Interaction model: QGSJET01c Gamma: 0.3TeV-10PeV, Crab Orbit E-2.6
Core position: Throw randomly within 300 m radius
Scintillation det. (Tibet AS) - Epics UV8.00 Estimate energy, direction, core position, …
Soil + Cherenkov det. (Tibet MD) - GEANT4 8.0 Reflectance at walls 70% Att. length ~40m@400nm (Dependant on wave length)
Quantum Eff. ~20%@400nm (Dependant on wave length)
Accidental muons 300 Hz/m2 x 9540m2 x 200 ns = ~0.57 muons/an air shower (Poisson noise distribution)
AS
MD
MD (Type2)
AS
3. Sensitivity Simulation
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Air Shower Reconstruction by AS Array Energy - Sum of particle density by all scintillation detectors (we do not use the lateral function in this talk.)Direction - Relative timings at each detectors
~10 TeV Air Shower (Simulation)
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Energy & Angular Resolution (Simulation)
10 TeV ~+70%-40%100 TeV ~+40%-30%(Gamma rays)
10 TeV ~0.4 degrees100 TeV ~0.2 degrees(Gamma rays)
Energy Resolution Angular Resolution
two typical air-shower size bins
~10 TeV
~100 TeV
10TeV 100TeV 1000TeV
11NPE
~100TeV
NPE
~10TeV
Muon Number vs. Shower Size (Type2 Simulation)
( Shower Size)
NP
E(
Muo
n N
um
ber)
10TeV 100TeV 1000TeV
20%50%80%
: Sum of particle density by all scintillation det. Shower SizeNPE:Sum of photoelectrons by all muon det. Muon number G CR
G CR
0
0
10TeV:Cut value NPE=~40Background: ~99% RejectionGamma rays: ~60% SurvivalSensitivity: ~6 times Improved
100TeV:Cut value NPE=~600Background: >99.8% RejectionGamma rays: ~100% SurvivalSensitivity: >20 times Improved
(gamma)
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Survival Efficiency (Type2 Simulation)
CR
Gamma
10TeV 100TeV 1000TeVE:10 TeV:Cut value NPE=~40Background: ~99% RejectionGamma rays: ~60% SurvivalSensitivity: ~6 times Improved
100 TeV:Cut value NPE=~600Background: >99.8% RejectionGamma rays: ~100% SurvivalSensitivity: >20 times Improved Almost background free!
1000 TeV:Cut value NPE=~8000Background: >>99.8% RejectionGamma rays: ~100% SurvivalSensitivity: Background free!
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Tibet AS Array 50,000m2
+Tibet MD Array
9,540m2
Crab orbit
Sensitivity to Point-like Gamma-ray Source
EGRET
GLASTMAGIC
VERITAS
HESS
Tibet AS
Tibet AS+MD (Type2)Tibet AS+MD (Type1)
Search window size0.3 degrees >50TeV,while angular resolution<0.3 degrees.
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4. Outlook
Tibet AS+MD~100 TeV
HESS~200 GeV
Location 30N-90E 23S-16E
F.O.V. ~1.5 sr ~0.02 sr
Duty Cycle ~90% ~10%
Angular Resol. ~0.2° ~0.1°
Energy Resol. ~40% ~20%
BackgroundRejection
>99% ~99%
Sensitivity(RX J1713 Unit PL Index = –2.19)
~5% RXJ1713(1 year 5σ)
~1% RXJ1713(50 hours 5σ)
Number of detections ? >20
Tibet AS+MD ability will be close to HESS.How many sources can we detect in the 100 TeV Northern Sky?
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Known Galactic Sources in the Northern Sky
TeV J2032+4130 HESS J1837-069 HESS J1834-087
Cas A LS I +01 303
Large Zenith ~ 37o Large Zenith ~ 39o
Periodic objectMAGIC - Peak flux
MGRO J2019+37
Diffuse gammaflux is corresponding to(3.0 x 3.0 deg.)
Our sensitivityVery preliminary!
Type 1Type 2
VERITAS
Extrapolation
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How Many New Sources?
Induces are harder
Aharonian et al, ApJ, 636, 777 (2006)
(If it is constructed at southern hemisphere)Most of new HESS sources detectable by Tibet AS+MD
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Green, arXiv:astro-ph/0411083http://www.mrao.cam.ac.uk/surveys/snrs/index.html
Green’s SNR catalog
HESS survey region82 SNRs
Tibet F.O.V. region86 SNRs
~new 14 detected (SNR-like)~new 14 detectable?? (SNR-like)optimistic value?But, could not be 0?
Expectation of the number of SNR-like sources in the Northern Sky
Aharonian et al, ApJ, 636, 777 (2006)
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5. Costs
Items Remarks Unit price
(US $)
Quantity Total
(US $)
PMT 20” PMT 5,000 368 1.84M
ElectronicsADC, TDC, HV,
Cable, …800 184 0.147M
Water poolConstruction fee
(Waterproof paint, Concrete, … )
250/m2 9,540m2 2.39M
Water purification & circulation
MF filters, … 0.15M
Others +
Total (US $) 4.5M +
Total ~5M US$
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Tibet MD Project 50,000 m2 Tibet air shower array + 9,540 m2 Water cherenkov muon detector array
~5M US$ - 100 TeV gamma-ray wide sky survey.
Sensitivity simulation Detailed simulation was done (two configurations). F(>100TeV) ~2 x 10-15 cm-2 s-1 (1 calender year, 5or 10 events). Improve sensitivity by an order of magnitude. Inner MDs are very important.
Candidates of 100 TeV sources in the northern sky Promising: Crab, TeV J2032+4130, HESS J1837-069, MGRO J2019+37 Interesting: Cas A, HESS J1834-089, LS I +61 303 (Need several years)
+ several new sources?
6. Summary
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Tibet AS+MD200?~
CASA-MIA1991~1996
Milagro2000~
KASCADE1996~
Grapes-III2001~
Location 30.102N 90.522E Tibet 4300m(606g/cm2)
40.2N 112.8WUtah1500m(870g/cm2)
35.9N 106.7W NewMexico 2650m (750g/ cm2)
49.1 N8.4E Karlsruhe 110m(1022 g/cm2)
11.4N 76.7EOoty 2200m(800 g/cm2)
EnergyETH75%
1-104.5TeV10TeV
50-104.5TeV60TeV
~0.1TeV-?10TeV
100-104.5TeV260TeV
10-104TeV?
Energy Resolution
40% (100TeV) 100%(100TeV) ? ? ?
AngularResolution
0.4° (>10TeV)0.2° (>100TeV)
2 °(>~100TeV)0.5°(>~700TeV)
1°(>~1TeV)0.55°(>~600TeV)
?
AS Eff Area(Particle coverage)
50,000m2
Scinti. (0.9%)230,000m2
Scinti. (0.7%) 4,800m2 Water (100%) (with Outrigger 34,000m2)
40,000m2
Scinti.(1.3%)10,000m2
Scinti.(1.2%)
μ Eff Area 9,540m2
Water2,500m2
Scinti.~2,000m2
Water622m2
Scinti.560m2 x4 layersProp. Counters
Absorber Soil 2m +Concrete 0.5m(515g/cm2)19X0
Soil 3m
(600g/ cm2)22X0
Water 6m
(600g/ cm2)16X0
Lead 10cm +Iron 4cm(145g/cm2)20X0
Concrete 2m
(460g/cm2)17X0
Muon Eth >1GeV >1GeV >1.2GeV >0.23GeV >1GeV