A Fast and Compact Electromagnetic Calorimeter for the Detector at GSI Bernd Lewandowski...
-
Upload
noe-jessop -
Category
Documents
-
view
217 -
download
2
Transcript of A Fast and Compact Electromagnetic Calorimeter for the Detector at GSI Bernd Lewandowski...
A Fast and Compact Electromagnetic Calorimeter for the
Detector at GSI
Bernd LewandowskiBernd LewandowskiRuhr-Universität BochumRuhr-Universität Bochum
SCINT 2003SCINT 2003ValenciaValencia
11. 9. 200311. 9. 2003
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 22
WhatWhat isis PANDA? PANDA?
AntiProtonANnihilations
at DArmstadt
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 33
Where is Darmstadt?Where is Darmstadt?
GSI
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 44
The GSI Future FacilityThe GSI Future Facility
Panda
Existing GSI Facilities
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 55
Antiproton Physics ProgramAntiproton Physics Program
Charmonium (cc ) spectroscopy: precision measurements of mass, width, decay branches of all charmonium states, especially for extracting information on qq models of mesons.
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 66
Antiproton Physics ProgramAntiproton Physics Program
Charmonium (cc ) spectroscopy: precision measurements of mass, width, decay branches of all charmonium states, especially for extracting information on qq models of mesons.
Search for gluonic excitations (charmed hybrids, glueballs) in the charmonium mass range (3 – 5 GeV/c2).
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 77
Antiproton Physics ProgramAntiproton Physics Program
Charmonium (cc ) spectroscopy: precision measurements of mass, width, decay branches of all charmonium states, especially for extracting information on qq models of mesons.
Search for gluonic excitations (charmed hybrids, glueballs) in the charmonium mass range (3 – 5 GeV/c2).
Search for modifications of meson properties in the nuclear medium,and their possible relationship to the partial restoration of chiral symmetry for light quarks.
pionic atoms
KAOS/FOPI
HESR
π
K
D
vacuum nuclear mediumρρ
π+
π-
K-
K+
D+
D-
25 MeV
100 MeV
50 MeV
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 88
Antiproton Physics ProgramAntiproton Physics Program
Charmonium (cc ) spectroscopy: precision measurements of mass, width, decay branches of all charmonium states, especially for extracting information on qq models of mesons.
Search for gluonic excitations (charmed hybrids, glueballs) in the charmonium mass range (3 – 5 GeV/c2).
Search for modifications of meson properties in the nuclear medium,and their possible relationship to the partial restoration of chiral symmetry for light quarks.
D
50 MeVD
D+
vacuumvacuumnuclear mediumnuclear medium
π
K
25 MeV
100 MeV
K+
K
π
π
Precision -ray spectroscopy of single and double hypernuclei for Extracting information on their structure and on the hyperon-nucleon and hyperon-hyperon interaction.
Antiproton Physics ProgramAntiproton Physics Program
-3 GeV/c
KKTrigger
_
secondary target
p
-(dss) p(uud) → (uds) (uds)
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 99
The Antiproton FacilityThe Antiproton Facility
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1010
The Antiproton FacilityThe Antiproton Facility
• Antiproton production similar to CERN, • HESR = High Energy Storage Ring
– Production rate 107/sec
– Pbeam = 1.5 - 15 GeV/c
– Nstored = 5 x 1010 p
• Gas-Jet (or Cluster) Target• High luminosity mode
– Luminosity = 2 x 1032 cm-2s-1
p/p ~ 10-4 (stochastic cooling)
• High resolution mode p/p ~ 10-5 (electron cooling < 8 GeV/c)– Luminosity = 1031 cm-2s-1
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1111
Proposed Detector (Overview)Proposed Detector (Overview)
• High Rates– Total ~ 55 mb– 107 interactions/s
• Vertexing– (p,KS,,…)
• Charged particle ID– (e±,±,π±,p,…)
• Magnetic tracking• Elm. Calorimetry
– (,π0,)• Forward capabilities
– (leading particles)• Sophisticated Trigger(s)
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1212
Electromagnetic CalorimeterElectromagnetic Calorimeter
Detector material PbWO4
Photo sensors Avalanche Photo Diodes
Crystal size 35 x 35 x 150 mm3 (i.e 1.5 x 1.5 RM2 x 17 X0)
Energy resolution 1.54 % / E[GeV] + 0.3 % (PMT)
Time resolution 130 ps (PMT)
Total number of crystals 7150
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1313
Requirements for the EMCRequirements for the EMC
• Nearly 4π solid angle (PWA)
• High rate capability: 107 interactions/s
• High resolution: 1.54 % / E[GeV] + 0.3 %
• Compact design: inside Solenoid
• Operation in magnetic field: 2T
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1414
Lessons from LEAR (CB)Lessons from LEAR (CB)
• Final states with 10+ photons
• Merged π0 are easy to handle– “moderate” angular resolution sufficient
• Low thresholds– Emin≤20 MeV
Crystal BarrelCrystal Barrel
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1515
Property CsI(Tl) CeF3 PbWO4 BGO
Density [g/cm3] 4.53 6.16 8.28 7.13
Rad. length [cm] 1.85 1.68 0.89 1.12
Molière rad [cm] 3.8 2.63 2.19 2.33
dE/dx [MeV/cm] 5.6 7.9 13.0 9.2
Decay time [ns] 1000 10-30 5-15 60-300
Max. emission [nm]
565 310-340 420-440 480
Rel. lightyield 0.40 0.10 0.01 0.15
Available Inorganic ScintillatorsAvailable Inorganic Scintillators
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1616
PWOPWO
• Fast Scintillator
• Allows a very compact design
• Low cost material
• But: light yield too low for detection
of low energy photons
• Improvement of light yield• Cooling (LY changes with temperature)
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1717
PWO ImprovementPWO Improvement
photon response: E = 45 -770 MeV@MAMI
0 50 100 150 2000
500
1000
1500
2000
co
un
ts [
a.u
.]
energy [a.u.]
E=45.4 MeV
0 50 100 150 200 250 300 350 400 4500
200
400
600
800
1000
cou
nts
[a.u
.]
energy [a.u.]
E=105.6 MeV
/E=5.3%/E=7.4%cou
nts
energy / a.u.
PMTreadout
further significant increase of light output achievable by:
• improvement of growing technology PWO II(exploiting large experience with CMS/ECAL production)
• optimum co-doping
1 410 90
. %. %
E E[GeV]
ps130~t
CMS/ECAL
R. Novotny et al.,II. Phys. Inst. GI
Bogoroditsk TCP
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1818
PWO ImprovementPWO Improvement
M.Korzhik et al., RINC, MinskA.Hofstaetter et al., I. Phys. Inst. GI
crystal imperfections:
• cation vacancies (Pb)• anion vacancies (O)• insite oxygen• excess of doping ions
results based on EPR:• Frenkel defects reduced ( factor >3)• Pt identified - impact on quenching?• oxygen based defects reduced
• Frenkel defects reduced ( factor >3)• Pt identified - impact on quenching?• oxygen based defects reduced
0
500
1000
1500
2000
0 100 200 300 400 500 600
channel
coun
ts
Cs-137662 keV
0
500
1000
1500
2000
0 100 200 300 400 500 600
channel
coun
ts
Cs-137662 keV 137Cs: L.Y.: 43 phe/MeV
„2 times CMS-standard“@ T = 20°C
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 1919
PWO light yeild
0
10
20
30
40
50
60
70
80
90
-7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
T, Celsium degree
LY,
ph
e/M
eV
PWO light yeild
0
10
20
30
40
50
60
70
80
90
-7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
T, Celsium degree
LY,
ph
e/M
eV
PWO CoolingPWO Cooling
line shape: @T=200C1= 6.5ns (97%)2=30.4ns ( 3%)
PWO
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 20 40 60 80 100 120 140 160 180 200
Time, ns
Lig
ht
frac
tio
n,
arb
. u
nit
s
T= -6C
T= -2C
T= 9C
T= 14C
PWO
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 20 40 60 80 100 120 140 160 180 200
Time, ns
Lig
ht
frac
tio
n,
arb
. u
nit
s
T= -6C
T= -2C
T= 9C
T= 14C
fraction of light yield collected in different integration gates at various temperatures
change of light yield collectedwithin 100ns as a function oftemperature
R. Novotny et al.,II. Phys. Inst. GI
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2020
PWO FuturePWO Future
Ongoing developements in PWO productionwill increase the light yield. Light yield improvement of PWO scintillation crystals for the
PANDA detectorA. Borisevich, V. Dormenev, A. Hofstaetter, V. Ligoun,M. Kozhik, B. K. Meyer, R. Novotny
Combined with cooling andmaximum coverage of readout side by
photosensor can make PWOthe scintillator of choice for the PANDA EMC.
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2121
PhotosensorPhotosensor
5 mmAPD Hamamatsu S8664-55• „Photodiode with internal amplification“• operates in B-Field• High quantum efficiency• Active area 5x5mm2
• Large experience with CMS/ECAL Extremely reliable and robust• but: gain, dark current are temp. dependend T < 1°C
Others to be investigated:• Large Area APDs of other manufacturers• Channel Plate Multipliers• Vacuum Triodes, …
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2222
APD readout: CsI(Tl)APD readout: CsI(Tl)
137Cs @ T = 0 °C
ADC channel
Ent
ries
662 keV
ADC channel
662 keV
E Ε 16% E Ε 29%
Ent
ries
50 mm60
mm
50 mm
60 m
m
APD (Hamamatsu) readoutactive area: (5 x 5) mm2
PMT ( R1635 ) readoutactive area: Ø 10 mm
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2323
APD Quantum EfficiencyAPD Quantum Efficiency
CeF3
BGO
PWO
CsI(Tl)
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2424
Property CsI(Tl) CeF3 PbWO4 BGO
Density [g/cm3] 4.53 6.16 8.28 7.13
Rad. length [cm] 1.85 1.68 0.89 1.12
Molière rad [cm] 3.8 2.63 2.19 2.33
dE/dx [MeV/cm] 5.6 7.9 13.0 9.2
Decay time [ns] 1000 10-30 5-15 60-300
Max. emission [nm]
565 310-340 420-440 480
Rel. lightyield 0.40 0.10 0.01 0.15
Available Inorganic ScintillatorsAvailable Inorganic Scintillators
Property CsI(Tl) CeF3 PbWO4 BGO
Density [g/cm3] 4.53 6.16 8.28 7.13
Rad. length [cm] 1.85 1.68 0.89 1.12
Molière rad [cm] 3.8 2.63 2.19 2.33
dE/dx [MeV/cm] 5.6 7.9 13.0 9.2
Decay time [ns] 1000 10-30 5-15 60-300
Max. emission [nm]
565 310-340 420-440 480
Rel. lightyield 0.40 0.10 0.01 0.15
Property CsI(Tl) CeF3 PbWO4 BGO
Density [g/cm3] 4.53 6.16 8.28 7.13
Rad. length [cm] 1.85 1.68 0.89 1.12
Molière rad [cm] 3.8 2.63 2.19 2.33
dE/dx [MeV/cm] 5.6 7.9 13.0 9.2
Decay time [ns] 1000 10-30 5-15 60-300
Max. emission [nm]
565 310-340 420-440 480
Rel. lightyield 0.40 0.10 0.01 0.15
We‘ll come back to this in a minute.
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2525
BGOBGO
First tests with
L3 crystals:
APD readout
Temp controlled environmentT=1°Ccontrolled humidity 30% rel.
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2626
APD readout: BGOAPD readout: BGO
14%1275keV)ΕE (
APD
ADC channel
22Na511 keV
1275 keV
22.5%1275keV)ΕE (
ADC channel
22Na
511 keV
1275 keV
PMT R1635
25%511keV)ΕE (
25 mm
25 m
m
25 mm
25 m
mEnt
ries
Ent
ries
T=0°C
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2727
BGO time resolutionBGO time resolution
PANDA:• 107 events/s 10 ns time resolution• MC: max. single crystal rate: ~200·103/s
BGO timing test:• L3 BGO crystal• Hamamatsu APD• BABAR preamp (250 ns shaping)• Digital Scope• Record a sample of cosmics signals (~15 MeV)
Make a simple MC test
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2828
point of time measurement
Linear fit
BGO time resolutionBGO time resolution
BGO
Landau fit + DC offset• Use Landau func. to simulate pulses
• Typical: N/S=0.5%
Vary S/N and FADC sampling freq.
• Linear fit of rising edge• Determine time when fit reaches half the signal amplitude
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 2929
BGO time resolutionBGO time resolution
σt [ns]ΔTSamples [ns]N/S [%]σv [V]
4.6501.00.02
9.7502.00.03
2.51000.50.01
5.51001.00.02
10.21002.00.03
41.9505.00.04
2.4500.50.01
46.52005.00.04
12.32002.00.03
6.22001.00.02
2.82000.50.01
39.81005.00.04
5 samples on rising edge
3 sampleson rising edge
10 sampleson rising edge
}}}
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3030
BGOBGO
• BGO has sufficient light yield
• Timing can be handled by adequate electronics
We will perform furtherinvestigations with BGO
as an option for the Panda Emc
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3131
Summary & OutlookSummary & OutlookR&D tasksR&D tasks
• Improvement of PWO light yieldImprovement of PWO light yield• Detailed time resolution studies for BGODetailed time resolution studies for BGO• Tests of APD readoutTests of APD readout
and radiation damageand radiation damage– Planned this year: Planned this year:
testbeam @ KVI, MAMItestbeam @ KVI, MAMI
• Development of largeDevelopment of large
area APDs (100mmarea APDs (100mm22))
by Hamatsuby Hamatsu• Tests of otherTests of other
PhotosensorsPhotosensors
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3232
Panda CollaborationPanda Collaboration
At present a group of 150 physicists
from 40 institutions of 9 Countries.
Bochum, Bonn, Catania, Cracow, Dresden, Dubna I + II, Edinburg, Erlangen, Ferrara, Frascati, Genova, Giessen, Glasgow, KVI
Groningen, FZ Jülich I + II, Los Alamos, Mainz, Milano, TU München, Münster, Northwestern,
BINP Novosibirsk, Pavia, Silesia, Stockolm, Torino I + II, Torino Politecnico,Trieste, TSL
Uppsala, Tübingen, Uppsala, SINS Warsaw, AAS Wien
Bochum, Bonn, Catania, Cracow, Dresden, Dubna I + II, Edinburg, Erlangen, Ferrara, Frascati, Genova, Giessen, Glasgow, KVI
Groningen, FZ Jülich I + II, Los Alamos, Mainz, Milano, TU München, Münster, Northwestern,
BINP Novosibirsk, Pavia, Silesia, Stockolm, Torino I + II, Torino Politecnico,Trieste, TSL
Uppsala, Tübingen, Uppsala, SINS Warsaw, AAS Wien
http://www.gsi.de/hesr/panda
Spokesperson: Ulrich Wiedner - UppsalaDeputy: Paola Gianotti - LNF
Austria - Germany – Italy – Netherlands – Poland – Russia – Sweden – U.K. – U.S.
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3333
Appendix
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3434
TargetTarget
An internal cluster-jet/pellet target is under study: 1016 atoms/cm2 for D=20-40 m
Pellet target layoutPellet target layout
Cluster-jet target layoutCluster-jet target layout
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3535
Vertexing: Micro Vertex DetectorVertexing: Micro Vertex Detector
7.2 mio. barrel pixels50 x 300 μm
2 mio. forward pixels100 x 150 μm
beam pipepelle
t/cl
ust
er
pip
e
Readout: ASICs (ATLAS/CMS) 0.37% X0
or pixel one side – readout other side (TESLA)
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3636
Tracking: Straw Tube TrackerTracking: Straw Tube Tracker
Number of double layersSkew angle of dbl layers 1 and 15 Skew angle of dbl layers 2-14
150o
2o-3o
Straw tube wall thicknessWire thicknessGas
LengthDiameter of tubes in double layers 1-5, 6-10, and 11-15Number of straw tubes
26 mm20 mm90%He10%C4H10 150 cm4 mm6 mm8 mm8734
Transverse resolution sx,y
Longitudinal resolution sz
150 mm 1 mm
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3737
Tracking: Forward MDCTracking: Forward MDC
• 6 layers of sense wires in• 3 double layers (y,u,v)• not stretched radially
(mass)• realized at HADES
– high counting rates – position resolution 70μm
HADES@GSI
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3838
PID: DIRC (Cherenkov)PID: DIRC (Cherenkov)
less space than aero gel costs of calorimeterno problems with field
BaBar@SLAC
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 3939
PID: Forward RICHPID: Forward RICH
Aerogel n=1.02
Multi pad gasDetector
Mismatch photons CsI photon conversion
LHCbLHCb
proximity focusing mirrors
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 4040
APD Hamamatsu S8664-55APD Hamamatsu S8664-55
5 mm
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 4141
CeFCeF33
0 200 400 600 800 10000
500
1000
1500
2000
2500
3000
3500E = 55 M eV
7 6 9 M eV
480 M eV
227 M eV
G E A N TG E A N T
ex p er im en tex p er im en t
en e rg y / M eV
coun
ts/a
.u.
0 200 400 600 800 10000
500
1000
1500
2000
2500
3000
3500E = 55 M eV
7 6 9 M eV
480 M eV
227 M eV
G E A N TG E A N T
ex p er im en tex p er im en t
en e rg y / M eV
coun
ts/a
.u. %70.2
]GeV[E
%17.2
E
limited resolution for photons due to:
• imperfection of crystals• insufficient size
in spite of high luminescence yield
85 MeV p + C @ KVI
proton energy / MeV
cou
nts
10 20 30 40 50 60 70 80 90 1000
50
100
150
200
10 20 30 40 50 60 70 80 90 1000
400
800
1200
10 20 30 40 50 60 70 80 90 1000
50
100
150
10 20 30 40 50 60 70 80 90 1000
40
80
2 x 2 x 15 cm3
2 x 2 x 14 cm3
1.5 x 1.5 x 1.5 cm3
CeF3
TAPS geometry 25 cm
BaF2
PbWO4
PbWO4:Mo
high energy photon detectionlow energy proton detection
@MZ
good resolution for protons due to:
• high light output• localized energy deposition
general applicability proven !
R. Novotny et al., II. Phys. Inst. GIin collaboration with Korth-Kristalle GmbH
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 4242
CeFCeF33
• CeF3 needs further R&D to improve resolution for photons
• Rel. long X0
compact design not possible (compared to PWO)
• Constraints from targetmay limit the available space for the EMC CeF3 is not an option for the barrel part
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 4343
BGO: event ratesBGO: event rates
• Max. occupancy of one crystal due to bkgr simulations:
2% · 107 events/s = 2·105 s-1
• Use digital tail cancelation in the feature extraction
• conservative scaling of the rise time
– CsI: 100 ns / 940 ns– BGO: 12 ns / 200 ns
• Rate we can handle: ( 2·trise· 10 )-1 = 2.5·105 events/s
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 4444
Why Antiprotons?Why Antiprotons?
•high resolution spectroscopy with p-beams in formation experiments: E Ebeam
•high yields in pp of gluonic excitations– glueballs, hybrids
•event tagging by pair wise associated production,– (particle, anti-particle) e.g. ppbar
•large √s at low momentum transfer– important for in-medium "implantation" of hadrons:– study of in-medium effects
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 4545
TimelineTimeline
•since 1996 Discussion about GSI futureInternational workshops, reviews, accelerator R&D
•May 1999 Letter of Intend for an antiproton facility (40 authors) Studies for detector concept
•Jan. 2001 Detector simulation with GEANT4•Nov. 2001 Conceptual Design Report
of an „International Accelerator Facility forBeams of Ions and Antiprotons”
•Nov. 2001 Review by an international review committee of the „Deutscher Wissenschaftsrat“
•April 2002 International p-Workshop at GSI•July 2002 Positive Votum by the „Deutscher Wissenschaftsrat“•Feb. 5, 2003 Positive Decision by the „bmb+f”
11. 9. 200311. 9. 2003 Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003Bernd Lewandowski - Ruhr-Universität Bochum - SCINT 2003 4646
Resonance ScanResonance Scan
ECM
Measured Rate
Beam Profile
Resonance Cross
Section
small and well controlled beam momentum spread
p/p is extremely important