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KEK Test Beam Phase I (May 2005). Makoto Yoshida Osaka Univ. MICE-FT workshop @ Daresbury Aug 30th, 2005. Contents. KEK beam test (KEK-PS T571) Equipments Setup TOF hodoscopes Timing resolution Operation in magnetic field Aerogel Cherenkov Counter (ACC) - PowerPoint PPT Presentation
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KEK Test BeamKEK Test BeamPhase I (May 2005)Phase I (May 2005)
Makoto YoshidaMakoto YoshidaOsaka Univ.Osaka Univ.
MICE-FT workshop @ DaresburyMICE-FT workshop @ DaresburyAug 30th, 2005Aug 30th, 2005
ContentsContents
KEK beam test (KEK-PS T571)KEK beam test (KEK-PS T571) EquipmentsEquipments SetupSetup
TOF hodoscopesTOF hodoscopes Timing resolutionTiming resolution Operation in magnetic fieldOperation in magnetic field
Aerogel Cherenkov Counter (ACC)Aerogel Cherenkov Counter (ACC) Response for pions, muons and electronsResponse for pions, muons and electrons
Beam surveyBeam survey Focusing magnetsFocusing magnets Lead diffuserLead diffuser muon rate in low momentum beammuon rate in low momentum beam
KEK-PS T571KEK-PS T571 May 26May 26thth – June 2 – June 2ndnd at KEK-PS at KEK-PS 2 beam line2 beam line Super-conducting solenoidSuper-conducting solenoid
1T magnetic field1T magnetic field 40cm x 40cm TOF hodoscopes40cm x 40cm TOF hodoscopes
// separation by TOF separation by TOF Momentum measurement for low momentum particlesMomentum measurement for low momentum particles
Aerogel Cherenkov counterAerogel Cherenkov counter Refractive index : 1.05Refractive index : 1.05 Discriminate Discriminate ///e by light yield in combination with T/e by light yield in combination with T
OFOF
Q3Q4
D4
SetupSetup
TOF hodoscope
Defining Counters
AerogelT12cm-thickscintillator Diffuser
Super conducting solenoidSuper conducting solenoid
length1.3m
φ 850 mm
Super-JACEEfor balloon experiment Front view
Side view
1Tesla Magnetic field
Downstream TOF CounterDownstream TOF Counter Fine mesh PMTFine mesh PMT
R6504S ,19DYR6504S ,19DY Shape of TOF using guide7Shape of TOF using guide7
Long light guideLong light guide Magnetic field is not parallel Magnetic field is not parallel
to PMT axisto PMT axis Could cause spoil of PMT gainCould cause spoil of PMT gain
Momentum for beam testMomentum for beam test 300 – 600 MeV/c300 – 600 MeV/c
Particle identificationParticle identification 33 // separation @600MeV/c separation @600MeV/c TOF TOF < 230 ps< 230 ps
Up stream : 50psUp stream : 50ps Down stream Down stream (( hodoscope) : 50pshodoscope) : 50ps
TOF hodoscope
Defining counter / TOF hodoscoDefining counter / TOF hodoscopepe
Defining counterinside solenoid
5x5 TOF hodoscope
TOF 1 5
TO
F 6
1
0
Test for TOF performanceTest for TOF performance
Calibrate TOF counters in 40cm x 40cm Calibrate TOF counters in 40cm x 40cm large arealarge area upstream TOF counter upstream TOF counter ~40ps~40ps Diffuser (5cm-t lead block) Diffuser (5cm-t lead block) Negative 3GeV/c (Negative 3GeV/c ()) Solenoid ON/OFFSolenoid ON/OFF
T1 5cm lead block
TOF hodoscope
~30cm
~900cm
Finger counter
Timing resolution of TOF hodoscTiming resolution of TOF hodoscopeope
3Gev/c 3Gev/c
w/o magnetic fieldw/o magnetic field (TOF8-T1)=77.3ps(TOF8-T1)=77.3ps (T1)=41.8ps(T1)=41.8ps TOFTOF)=65.0ps)=65.0ps
TOF8-T1400ps-400ps
Timing resolutionTiming resolutionin fringing magnetic fieldin fringing magnetic field
No significant loss of timing resolution in magnetic field
timing resolution of TOF
60
65
70
75
80
85
90
95
0 1 2 3 4 5 6 7 8 9 10 11
TOF number
tim
ing r
eso
luti
on
w/o magnetic fieldw/ magnetic field
Timing resolution of hodoscopeTiming resolution of hodoscope w/o magnetic fieldw/o magnetic field (hodoscope)=53.6ps(hodoscope)=53.6ps
(Average of horizontal and vertical TOF counters) -T1
σ= 68.0ps σ= 67.5ps
w/ magnetic fieldw/ magnetic field (TOFhodoscope)=53.0ps(TOFhodoscope)=53.0ps
Position dependence of TOF Position dependence of TOF resolutionresolution
w/o magnetic fieldw/o magnetic field w/ magnetic fieldw/ magnetic field
No significant position dependence : 50ps-60ps
Improvement of AerogelImprovement of Aerogel Development of ACC used for redandunt PID of e,Development of ACC used for redandunt PID of e, in SciFi tracker in SciFi tracker
test.test. Aerogel in Feb. 2005Aerogel in Feb. 2005
refractive index n=1.03refractive index n=1.03 Effective momentum range : 426 - 565MeV/cEffective momentum range : 426 - 565MeV/c
Npe was measured to be 18 p.e for electrons.Npe was measured to be 18 p.e for electrons. New AerogelNew Aerogel
Adapt to low momentum m beamAdapt to low momentum m beam The Aerogel (index = 1.05) was selected in May,2005.The Aerogel (index = 1.05) was selected in May,2005.
PID in the range of 328 - 434MeV/c is possible.PID in the range of 328 - 434MeV/c is possible. Furthermore the Aerogel have some advantage. It is new type Aerogel Furthermore the Aerogel have some advantage. It is new type Aerogel
developed by Matsushita Electric Works, Ltd. and improved on transdeveloped by Matsushita Electric Works, Ltd. and improved on transparency (over 90%).parency (over 90%).
ACC performanceACC performance0.425GeV/c Negative
e
ACC light yieldACC light yield
Fit left edge of ADC distribution wFit left edge of ADC distribution with Gaussianith Gaussian tail on the right cannot be descritail on the right cannot be descri
bed by Poisson distributionbed by Poisson distribution tail could be caused by after-pulstail could be caused by after-puls
e in Fine-Mesh PMTe in Fine-Mesh PMT need to select proper gate widthneed to select proper gate width
Light yield of ACC = 32 p.e.Light yield of ACC = 32 p.e. ADC mean = 46.8ADC mean = 46.8 ADC sigma = 8.3ADC sigma = 8.3 (46.8/8.3)(46.8/8.3)22 = 32 p.e. = 32 p.e.
Performance is improved significPerformance is improved significantlyantly Feb. 2005: 18 p.e. (n=1.03)Feb. 2005: 18 p.e. (n=1.03) May 2005: 32 p.e. (n=1.05)May 2005: 32 p.e. (n=1.05)
Cross check for ACC light Cross check for ACC light yieldyield
Npe is proportional to 1-1/Npe is proportional to 1-1/((22nn22)) Npe = 0 Npe = 0 n n22=1/=1/22
Scan beam momentum froScan beam momentum from 325 MeV/c to 450 MeV/m 325 MeV/c to 450 MeV/cc
Measured refractive index oMeasured refractive index of the ACC is 1.051f the ACC is 1.051
Our calculation in the previoOur calculation in the previous slide is confirmed to be us slide is confirmed to be validvalid
(1.051)2
1/2
22
11
nNpe
Defining counter efficiencyDefining counter efficiency
Good efficiency > 99%
40cm x 40cm
24cm x 24cm
Focusing studyFocusing study
x= 11.5y= 10.8
x=11.9y=11.3
x=11.6y=11.0
Q=68Q4=52
Q=117Q4=161
Q=83Q4=73
Modification on focusing magnet current for 0.3GeV/c beam does not affect on beam profile so much
Q3Q4D4
Diffuser studyDiffuser studyMag. ONMag. ON Mag. OFFMag. OFF
Pb: 0Pb: 0 x : 6.6 cmx : 6.6 cmy : 6.4 cmy : 6.4 cm
9.59.5
7.17.1
Pb: 5mmPb: 5mm 10.310.3
9.49.416.316.3
13.813.8
Pb: 10mmPb: 10mm 10.910.9
10.310.318.618.6
14.914.9
Pb: 15mmPb: 15mm 11.611.6
10.710.719.019.0
15.815.8
Pb: 20mmPb: 20mm 11.611.6
10.910.921.821.8
15.815.8
Beam divergence w/o solenoid increase to ~20cm/200cm=100mrad @15mmPb
-0.3GeV/c
Muon yield in low momentum Muon yield in low momentum beambeam
-0.3GeV/c
-0.4GeV/c
5475 16min=6Hz
9000 10min=15Hz
e
SummarySummary
Beam test with SC solenoid was performed at KEK-PS Beam test with SC solenoid was performed at KEK-PS 2 beam line during May 262 beam line during May 26thth – June 2 – June 2ndnd
TOF performance was checked in magnetic fieldTOF performance was checked in magnetic field Intrinsic resolution of the counter better then 70psIntrinsic resolution of the counter better then 70ps Resolution of the TOF hodoscope (average of horizontal & verticaResolution of the TOF hodoscope (average of horizontal & vertica
l) ~ 50-60ps l) ~ 50-60ps ACC (refractive index = 1.05) was testedACC (refractive index = 1.05) was tested
good performance to discriminate good performance to discriminate ///e at 0.425GeV/c/e at 0.425GeV/c Beam parameter was surveyed to be optimized for AutumBeam parameter was surveyed to be optimized for Autum
n beam testn beam test The effect of lead diffuser was measured, will be comparThe effect of lead diffuser was measured, will be compar
ed with simulations. ed with simulations.
TOF measurement by VME TOF measurement by VME TDCTDC
S=180ps
S=150ps
+1GeV/cTOF at center
w/o timewalkcorrection
• CAEN V1290• 25ps resolution• 16 LEMO inputs• multi-hit/multi-event buffer (32k x 32 bit)
VME ADC .vs. TDCVME ADC .vs. TDC
TOF2BTOF2A
Something mis-configuration on the ADC module for TOF counters
• CAEN V792• 12bit resolution• 32 inputs with 2 flat connectors• multi-event buffer (32 events)