Report from the

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Report from the the CALICE Collaboration
164 Physicists 26 Institutes 9
Countries 3 Regions
CAlorimeter for the LInear Collider with
Electrons A calorimeter optimized for the
Energy Flow measurement of multi-jet final
states at the Future Linear Collider running at
a center-of-mass energy 90 GeV and 1 TeV
José Repond Argonne National Laboratory
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Electromagnetic Calorimeter Silicon
Tungsten France, UK friends
Silicon Scintillator LCCAL
Italy Not part of CALICE
Hadronic Calorimeter Analog readout
Tile HCAL Germany, Czech,
Russia Digital readout DHCAL
I Gas Electron Multipliers (GEMs)
Texas at Arlington II
Resistive Plate Chambers (RPCs)
Russia, USA (ANL, Boston, Chicago, FNAL)
III Scintillator
Northern Illinois IV Short Drift
Tubes (SDTs) Protvino
Will report on these Others covered by
individual talks at this workshop
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Structure 2.8 (21.4mm of W plates)
CALICE ECAL
Structure 4.6 (31.4mm of W plates)
Structure 1.4 (1.4mm of W plates)
Metal insert
Fine granularity tracking calorimeter Silicon
Tungsten sandwich 1 x 1 cm2 pads
40 layers Simulated energy
resolution Prototype for test
beams 30 layers Active
area 18 x 18 cm2 9720 channels
Goal first tests in 2004
Detector slabs
ACTIVE ZONE
1010 mm2
60 mm
Si Wafer with 66 pads
60 mm
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Detector slab
Transverse view
Silicon wafer (0.525 mm)
PCB (multi-layers) (? 2.4 mm)
Al. Shielding
8.5 mm
PCB 14 layers Thickness 2.4 mm
Composite structure (0.15 mm / layer)
Tungsten (1.4 mm, 21.4 or 31.4 mm)
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PCB, Wafers, Chips
PCB board
Chips
Wafer
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Front-end electronics ASIC
Measurements on FLC_PHY1 Linearity
0.3 Dynamic range
3.5 pC Noise
2200 e- Pedestal dispersion s5mV
Satisfactory
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Rear-end electronics
Developed in the UK Use of CMS Back end
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Schedule
Mechanical structure Tungsten plates by end
of 2003 Assembly in early 2004 FE ASICs
FLC_PHY2 tested by September Choice of ASIC
Production completed by end of 2003 FE PCB
boards Built by February 2004 RE boards
Fabrication and assembly in Mar03
Prototype in beam Cosmic rays first half of
2004 Electrons by mid 2004
Hadrons in 2005
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LCCAL
Not part of CALICE
Collaboration Como, LN Frascati, Padova,
Trieste Concept Lead/scintillator plus
silicon
45 layers 25 x 25 x 0.3 cm3 Lead 5 x 5 x
0.3 cm3 Scintillator 3 layers of Silicon 1
x 1 cm2 pads at 2, 6, 12 X0
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Extensive Tests in Frascati Test Beam
Electrons and positrons 50 850 MeV
Energy selection 1 Up to 103 electrons/s
Energy resolution as expected Npe gt
5.1/layer ? p.e. statistics negligible
Uniformity of light collection at 10 20 level
?E?E
E (MeV)
Recently inserted Silicon pads
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Conclusions and Perspectives
LCCAL prototype Almost fully working More
Silicon pads are being constructed Third
Silicon layer will be fully equipped Test run at
Frascati Underway Energy response and
resolution as expected Merging Silicon and
Energy information understand multiple hits (gt1
e-) Two test beams at Higher Energy in
preparation PS and SPS (in 2003) Monte Carlo
Simulation Studies of hybrid technique to be
initiated
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Hadron Calorimeter
TESLA TDR
HCAL located inside 4T coil Thickness
4.5 ? Barrel 6.2 ? Endcap
Cell structure Iron 20 mm
Active medium 6.5 10.0 mm
Two options a) Analog hadron calorimeter
with scintillator b) Digital hadron
calorimeter with
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Analog HCAL
Scintillator tiles Area 5 x 5 ? 25 x 25 cm2
Thickness 5 mm Longitudinal segmentation
9 Barrel 12 Endcap
Tests of different plastic scintillator Fiber
routing optimization Selection of
wavelength-shifting fibers Coupling of
WLS-fibres to scintillator Clear fiber
selection Connection of WLS and clear
fibres Photodetectors
Strong RD program
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A few examples
Scintillator PolyVinylToluene based ? more
expensive BC-408, BC-404 PolyStyrene
based ? less light SCSN-81,
Kuraray, BASF-143
WLS Fiber Routing Stress on fiber ? ageing?
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WLS Fiber Diameter 1 mm, double clad
BC-91A BC-92 Y11(500ppm)
Treatment of fiber end Polishing End
reflector
Finer sandpaper
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Silicon Photomultipliers SiPMs
RD at MEPHI (Moscow) together with PULSAR
(Russian Industry)
Overall size 1.5 x 1.5 mm2 Sensitive area 1 x
1 mm2 Gain 2106 at Ubias 50 V Number of
pixels 576 ? 1000 Recovery time 100ns
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15 photo-electrons 1000 pixels SiPM mounted on
tile
4 8 photo-electrons 576 pixels Ubias 53 55 V
10 photo-electrons 576 pixels Ubias 54 V
With threshold at 20 photo-electrons
Dark rate 2 Hz MIP detection
efficiency 97.5
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Minical Array
Stack 27 layers of 9 tiles 5 x 5 x 0.5 cm3
scintillator
beam
Purpose Cosmic rays starting in August
Light Yield Uniformity of response
Calibration with MIPs Test of different
photo-detectors Long term ageing effects
LED monitoring Stability Dynamic
range Electron beam Energy
resolution Constant term Linearity
beam
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Outlook
Slide by V Korbel shown at Amsterdam Meeting

• 1. Enough LY from TFS (200 photons at
  photodetector)
• 2. APDs and SI-PMs are the photodetectors which
  do the task
• 3. Preamplifiers with low noise are essential
  (MIP-noise separation,calibration)
• 4. Minical test to establish calibration
  precision in summer
• 5. Now design of prototype boards for APD and
  Si-PMs (DUBNA)
• 6. Photodetectors, large quantity to order in
  summer
• 1000 APDs or
• 5000 Si-PMs or
• both types in relevant quantities e.g.
  250/3500
• 7. Prototype stack (1m3) will be build in summer
• 8. Assembly of PT-stack with TFS starts in Jan.
  2004
• 9. Spring 2004 is used to set up and calibrate
  all channels with cosmics.

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DHCAL Resistive Plate Chambers - RPCs
Only Russian effort (Protvino) for US effort
see separate talk
Developed RPCs Single gap of 1.2, 1.6 or 2.0
mm 1013 Ocm window glass as resistive plates
Tests with 16 pads of 1 x 1 cm2 Thickness 4.4
mm (without FEE) Gas mixtures Avalanche mode
TetraFluoroEthane IB SF6 95 98 5
5 2 Streamer mode TetraFluoroEthane
IB Ar/N2 80 10 10 Tests with
Protvino test beam

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Tests in avalanche mode
To give a few examples
Efficiency and pad multiplicity versus High
Voltage
Tests with different gases and
thresholds Best results for HV 8.2 kV
Threshold 2.2 mV Efficiency 99
Multiplicity 1.4
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Efficiency versus rate for avalanche and streamer
mode
Maximum rate Streamer mode 4 - 5 Hz/cm2
Avalanche mode 300 Hz/cm2
Pad multiplicity versus charge for different
anode thicknesses
The thinner the anode the smaller the
multiplicity
At optimal operating point 0.5 Hz/cm2
Noise rate versus High Voltage
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Comparison of operation modes
As an example for 1.2 mm gas gap
Avalanche Streamer
Gas mixture TFEIBSF6 9352 TFEIBAr 85105
HV working point 8.4 kV 7.0 kV
Induced charge 3.4 pC 300 pC
Threshold on 50 O 1 2 mV 50 200 mV
Efficiency gt 99 95
sq/Q 1 0.6
Pad multiplicity 1.5 1.4 1.5
Noise 0.5 Hz/cm2 0.1 Hz/cm2
Rate capability 300 Hz/cm2 4 5 Hz/cm2
Ageing effects None Observed
Favored
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Plans
December 2003 Beam tests with 20 layer
electromagnetic calorimeter 64 pads per
layer June 2004 Ready for production and
assembly of 1 m3 prototype
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DHCAL Short Drift Tubes - STDs
Being developed in Protvino
Efficiency and Multiplicity as function of
High Voltage
Cell size 1 cm2 x 3 mm Gas IB
Ar TFE 80 10 10
Currently using flammable gas exploring
performance with other mixtures
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DHCAL Readout schemes
Real challenge. 1 m3 prototype
400,000 channels!
IHEP Protvino Conditioning FPGA Serialiser
JINR Dubna Comparators FPGA VME
US groups Custom FE ASIC concentrator collector
Korea Testing entire chain of comparators and digital processing
Imperial College London Adapting ECAL readout scheme to A/DHCAL
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Readout at Protvino
Conceptual design Readout for 64 channels
I Conditioning (analog) II FPGA
(digital) III Serializer (readout
of several FPGA)
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Readout at Dubna
Price ( ) Prototype 5000 ch Thr.
JINR Apl. CPLD 0.4 0.04 READY End of 2003 7-10 mv
Comp Sh. Reg. 0.35 0.04 3-4
CMS ampl. US CPLD 0.37 0.04 READY Nov. 2003 US ? 2-5 mv
CMS amp.Bel CPLD 0.5?? 0.04 READY Nov. 2003 ? Minsk ? 3-6 mv
Bel. 0.5?? ??? 3-6 mv
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HCAL Mechanical Structure of 1 m3 Prototype
Structure 40 Layers Each 1 m2 20 mm
steel plates Weighs 6 tons!
Issues Material of absorber Steel
Stainless steel Tolerances on
thickness, flatness Active gap
Adjustable width Tolerances
Support plates, e.g. 2 mm steel Logistics
Tests in magnetic field, what B 1
or 2 stacks Who builds it
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More information and upcoming meetings
DHCAL meeting in Paris on 28-February-2003
http//polywww.in2p3.fr/flc/agenda_dhcal_280203.ht
ml
CALICE meeting in Amsterdam on 31-March-2003
http//polywww.in2p3.fr/flc/agenda_CALICE_310303.h
tml
ECFA/DESY LC workshop in Amsterdam, April 1 4,
2003
http//www.nikhef.nl/ecfa-desy/flashindex.html
DHCAL meeting at DESY on June 30, 2003
http//www.hep.anl.gov/repond/DHCAL_Jun_2003_Agend
a.ppt
A/DHCAL meeting at DESY around October 24, 2003