Tibet MD: 10,000m? underground Muon Detector10-100TeV能区世界上最灵敏的探测器MDarray50--- 12x16=192muondetectors(~10.000m2)1o---2.5munderground(~515g/cm2,~19X0)(u)入Eachmuon detector---Waterpool,madeof concrete--- 7.2mx7.2mx1.5m depth10---Whitewaterproofsurface455---20"inchPMTx2(HAMAMATSUR3600)X(m)
Tibet MD：10,000m2 underground Muon Detector 10-100TeV能区世界上最灵敏的探测器 MD array - 12 x 16 =192 muon detectors (~10,000 m2) - 2.5m underground (~515g/cm2, ~19X0) Each muon detector - Water pool, made of concrete - 7.2m x 7.2m x 1.5m depth - White waterproof surface - 20” inch PMT x 2 (HAMAMATSU R3600)
Inside view of MD prototype
Inside view of MD prototype
Number of muons vs. Shower SizeSurvival Efficiency(Simulation)(Simulation)1.9TeV10TeV100TeVEnergyoZNpE CutCXiVTinaatiov Set.10PEs~30PEs~910PEsvalueShower Size (a measure of energy)BG rejection95.4%~99.7%>~99.99%ENpe:Sumof photoelectrons byall muon det59%~99%survival~61%~11times2.8timesnSensitivityBGfreeimprovedimprovedEg:1.9101001000TeV→→土10°--raysCRS+CRs100S10Y-rays10I101010'010PrimaryEnergy(TeV)10102g104105
8 8 Sr :Sum of particle density by all scintillation det. Shower Size （a measure of energy） SNPE :Sum of photoelectrons by all muon det. the number of muons in air showers Eg: 1.9 10 100 1000 TeV 8 Number of muons vs. Shower Size (Simulation) Survival Efficiency (Simulation) Energy 1.9TeV 10 TeV 100 TeV SNPE cut value 10PEs ~30 PEs ~910 PEs BG rejection 95.4% ~99.7% >~99.99% g survival 59% ~61% ~99% Sensitivity 2.8 times improved ~11 times improved BG free