MEG Summary February 9, 2005 T. Mori for MEG Collaboration
Jan 11, 2016
MEG Summary
February 9, 2005
T. Mori for MEG Collaboration
Spokespersons: T.Mori, A.BaldiniTechnical Coordinator: S.Ritt
Detectors:• Beam line: PSI P.-R.Kettle• COBRA: KEK/Tokyo W.Ootani • Drift Chamber: PSI J.Egger• Timing Counter: Genova/Pavia/Roma G. Cecchet• Photon Detector: Tokyo/Pisa/KEK S.Mihara• Trigger: Pisa M.Grassi• DAQ/Elec.: PSI S.Ritt• Offline: C.Gatto/S.Yamada/F.Cei
The MEG Collaboration
Highlights in developments sine July 2004
Beam line Separator, BTS in construction
COBRA Fringing field problem ~solved
LXe Beam test w/ new PMTs, waveform digitizers, and wire alpha sourcesDetector cryostat in construction
5
Absolute time of LXe55 M
eV
high gainnormal gain
110 psec 103 psec
110 - 64 - 61 = 65 = 56 + 33 psec
LYSO targetIntrinsic from LR analysis depth
Background and Sensitivity
Jan 2004 Jan 2005Gamma Energy (%) 4.5-5.0*e+ Timing (nsec) 0.1*Gamma Timing <0.23* ~0.15**Gamma Position (mm) 4.5-9.0*Gamma acceptance >0.4*Muon rate (108/sec) 0.2-0.3 0.25-0.35Running Time (107sec) 4.0Accidental Rate (10-14) 2.3-3.5 1.9-3.0# Accidental Events 0.6 0.690% CL Limit (10-13) 1.2-1.7 0.9-1.4
* Measured **w/ new PMTs
More detailed calculation necessary
Schedule
Changes (~delays) in schedule
Beam line BTS construction
LXe Detector cryostat constructionPMT delivery
new problem arising -- solution foreseen
DC Troubles with cathode foil production
Noise from Zener diode
2005 2006J F M A M J J A S O N D J F M A
Beam Time Shutdown MEG MEG Shutdown
COBRATests
P
F
Field
MapBeam
Line
BTS
Test
Commiss.
Part 2Tgt Full Test
Drift
Chamber
Proto
Inst
Full
InstallationTiming
Counter
BG
TestTstInst
Full
Installation
LPT PMT testing + calibration
Full
Calorimeter
Cryogenics
Installation
Assembly +
TestTest
Trigger
Inst Inst
DAQDC
Electr.
Inst Inst
Manpower
Mostly in healthy situation
except:
beam line + targetMonte Carlo
Budget
We now have enough money for PMTs!
a new budget for construction in Japan ~400 PMTsadditional budget for ~110 PMTs in Italy
Then new problems arising…
LXe for last 300literselectronicsLXe calibration equipment proton beam?
PSI
1982 !!
PREVIOUS e EXPERIMENT
NOW: GLAST SPACE EXPERIMENTCRYSTAL CALORIMETER CALIBRATION
It is the old VDG of the Crystal Ball experiment ! !they have some problems: old device, max. VDG p-energy is 400 KeVout of resonance: -rate reduced by factor 5000
180 cm target-pipe