Extensive air shower 中国斜草我术大学 University of Science and Technology of China Development of gamma-ray air showers Development of cosmic-ray air showers Primary particle Primary particle (gamma ray) (e.g.iron nucleus) first interaction first interaction with nucleus in air (pair production) bremsstrahlung pion decays on nucleus in air pair production pion-nucleus interaction bremsstrahlung second interaction (C)1999 K.Bemlohr (C)1999 K.Bernl6hr Also pair productions,but also following cascade
Extensive air shower Also pair productions, but also following cascade
EAS array 中国斜学我术大学 University of Science and Technology of China Surface EAS Array -X 50m 20m 70m 100m Underaround Muon Hall AS-gamma experiment in Tibet
EAS array AS-gamma experiment in Tibet
Extensive air showers array 中国斜学我术大学 University of Science and Technology of China detect muon/electrons in air shower (scintillator/water cherenkov ) large FOV (~several sr) above 1 TeV large effective area (1e5 m^2) poor PSF(0.3 degree) continuous monitoring Milagro LHAASO HAWC
Extensive air showers array LHAASO • detect muon/electrons in air shower (scintillator/water cherenkov ). • large FOV (~ several sr) • above 1 TeV • large effective area ( > 1e5 m^2) • poor PSF (0.3 degree) • continuous monitoring Milagro HAWC
y-ray/cosmic ray discrimination 中国斜草我术大草 University of Science and Technology of China 10 10 Proton 10 105 ◆—Data:Background before cut(scaled) 10 -eData:Background after cut(scaled) 云 0 Gamma-ray ......Simulation:Gamma-ray power-law 102 ...Simulation:Gamma-ray log-parabola 10 10 10 10 10 10 Ne 10 Cosmic ray 03 10-5 rate before cut 103 10-4 105 Gamma-ray rate 106 FuKM2 A array:Crab△0<1° Cosmic ray rate 10-7 10 102 103 after cut E(TeV)
γ-ray/cosmic ray discrimination Cosmic ray rate before cut Cosmic ray rate after cut 10-5 Gamma-ray rate Ne N μ Proton Gamma-ray
Air Cherenkov telescope arrays 中国斜学我术大学 University of Science and Technology of China VHE gamma ray Detection technique: Imaging Atmospheric Earth atmosphere Cherenkov Telescopes Atmospheric shower (electromagnetic) 10 km Cherenkov cone 。120m 189mm 10
Air Cherenkov telescope arrays