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Forward spectrometer. TOF. RICH. H calo. E calo. PID via TOF. m. L =7 m. σ p. σ m. σ L. σ t. (. ). =. +. γ 2. +. p. t. L. σ p. = 0.005. p. σ t. = 50 ps. GEANT4 simulation. (in collaboration with S. Petersburg State Polytechnic University,
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Forward spectrometer TOF RICH H calo E calo PANDA Russia Workshop, ITEP April 18, 2008
PID via TOF m L =7 m σp σm σL σt ( ) = + γ2 + p t L σp = 0.005 p σt = 50 ps PANDA Russia Workshop, ITEP April 18, 2008
GEANT4 simulation (in collaboration with S. Petersburg State Polytechnic University, Experimental Nuclear Physics Department ) BC408 plastic scintillator 140*10*1.5 cm3 - without light guide - with light guides for 2” PMT (46 mm diameter) - with light guides for 1” PMT (24 mm diameter) PANDA Russia Workshop, ITEP April 18, 2008
Energy deposit Electrons 1GeV Ionization Bremsstrahlund Landau distributions Protons 200 MeV Ionization Gaussian distribution PANDA Russia Workshop, ITEP April 18, 2008
G4OpAbsorption –light attenuation G4OpRayleigh - Rayleigh scattering G4OpBoundaryProcess : dielectric - dielectric total internal reflection Fresnel reflection Fresnel refraction dielectric – metal G4OpticalSurface : polished ground G4 Optical photons Scintillation process only (no Cerenkov Photons) PANDA Russia Workshop, ITEP April 18, 2008
Light attenuation Nphot acc e (Z/205) ~ Nphot gen PANDA Russia Workshop, ITEP April 18, 2008
BC408 plate, light guides, polished surface PANDA Russia Workshop, ITEP April 18, 2008
Photon propagation time no light guide light guide for 2” PMT light guide for 1” PMT R2083 TTS=370 ps. R4998 TTS =160 ps. 370/ n = 6.8 ps. 160/ n = 5.3 ps. PANDA Russia Workshop, ITEP April 18, 2008
Test stand PANDA Russia Workshop, ITEP April 18, 2008
For this test we used plastic scintillator 15*15*15 mm3, 2 R4998 PMT and radioactive 90Sr β-source. Test stand 190 ps 100 ps PANDA Russia Workshop, ITEP April 18, 2008
Test stand 3 BC408 plates : 140*10*1.5 cm3 140* 5*1.5 cm3 100*10*1.5 cm3 6 PMT Hamamatsu: 4 - R4998 2 - R2083 Thanks to J.Ritman, Julich, KFI The prototype with BC408 plastic 140*5*1.5cm3 is ready for testing PANDA Russia Workshop, ITEP April 18, 2008
To Do MC simulation TOF Wall -Different optical surfaces and wrapping -Light guide geometry optimization -Implementation of PMT to GEANT4 PID (forward detector) TOF stand for real BC408 plastic -optimization of TOF resolution - test with radioactive sources, cosmic and on proton beam. PANDA Russia Workshop, ITEP April 18, 2008