GLD ECAL Beam Test at DESY Plan and outlook

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GLD ECAL Beam Test at DESY- Plan and outlook -

• Satoru Uozumi (Shinshu)
• Jan-30 2007 Japan-Korea Joint Meeting _at_ Shinshu
  Univ.

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Beam Test _at_ DESY(Feb 25 Mar 29 2007)

• Using 1-6 GeV positron beam, evaluate energy
  resolution, linearity, and position (or spatial)
  resolution.
• Have experience of full MPPC readout.
• - Worlds first trial !
• Show excellent performance of our detector to the
  world !

26 layers 468 channels
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DESY Beam-line
DESY II Electron Synchrotron
Veto counter (with a 2 x 2 cm hole)
Trigger counters (3 x 3 cm)
ECAL module
e-
x
y
x
y
e 16 GeV
Movable stage
Drift chambers (resolution several hundred mm)

• Beam can be defocused up to spot size 5 x 5 cm
• We can also collimate the beam, but intensity
  will be lost.
• Beam rate is order of 10 (_at_ 6 GeV) 300 Hz (_at_ 3
  GeV)
• with collimated beam
• Accelerator is always running, and we can have
  the beam
• anytime we want!

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3 Types of Modules
? WLSF readout by extrusion technique 13 layers
? WLSF readout 13 layers
? Direct readout 13 layers
?
?
?
?
?
?
We will examine 3 different combinations of the
modules.
F
R
Beam

• 13 layers

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Measurement Plan
Test fiber readout module
Setup
Test direct readout module
Test KNU module
MPPC dose test
withdraw
0 1 2
3 4 weeks

• MIP Calibration (once per a couple of days)
• Since only the positron beam is available,
• we need to remove all the tungsten plates
• Energy scan (1-6 GeV, with 0.5 or 1 GeV step)
• Position scan

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Movable stage

• Can perform precise x-y scan
• with accuracy of 1 mm
• A steel plate (60 x 100 cm) will be mounted on
  the green arms
• to put our test modules.

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Bias Voltage Control
Baseboard single channel
8 bit DAC (0-5 V)
80 - 0.96 79.04 V
To Slow-control PC
-0.96V
80V
HV supply
To MPPC

• We can set value of the DAC output for each
  individual MPPC with 0.02 V step
• (5 V / 8 bit 0.02 V / count)
• Need to prepare a text table which contains DAC
  counts for all the channels
• g Need mapping information to convert
• MPPC number - Strip position
  Electronics
• channel

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Data Analysis

• The data are stored with a binary format on
  dcache system.
• Expected raw data size is about 5 kB / events.
• (very rough estimate, with - 50 of
  uncertainty)
• We can access to the binary data using the Marlin
  analysis framework.
• Similar to CDF Run II analysis framework (my
  feeling)
• Need C basics
• http//Ilcsoft.desy.de/
• Using the Marlin framework, we will make root
  ntuples for quick analysis on the beam test.

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Analysis procedure

• Make ADC distribution for each individual strips.
• Convert ADC counts to number of fired pixels.
  g need to know accurate gain of the MPPCs.
  (Correct for P.D.E. variation with
  temperature, if necessary)
• Correct MPPC saturation effect using correction
  curve and get number of photoelectrons
  measured on each strip.
• Divide it with calibration constant ( p.e./MIP),
  and obtain number of MIPs measured on each strip.
• Evaluate Energy resolution and Linearity (add
  responses over all the strips),
• or evaluate position / spatial resolution

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Concern 1Gain and P.D.E. vary with temperature
change

• 30oC
• 25oC
• 20oC
• 15oC
• 10oC
• 0oC
• -20oC

DV0/DT (56.0 0.1) mV/oC
Can we really correct these effect just by
measuring temperature? (for example,
device-by-device variation of DV0/DT is small
enough?)
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Concern 2 correction curve
MPPC signal
1600
1600 pixel expected reponse curve
Light input (photoelectrons)
1600 pixels taken by peak height
1600 pixels Taken by charge ADC
By peak height
Light input (arbitrary)
Light input (arbitrary)
Tsukuba guys are still working to understand this
problem
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Beam Test Participants
DESY contacts Benjamin Lutz (Beni), Erika
Garutti
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Jobs _at_ Beam Test

• DAQ ace
• Online data monitoring
• (check pedestal, dead channel, etc)
• Data analysis software / ntuplization / event
  display
• Drift chamber operation and analysis
• MIP calibration analysis
• Gain calculation
• (MPPC and electronics inter-calibration)
• MPPC response correction
• Quick result of energy spectra / resolution
• Temperature / LED monitoring data, correction
• MPPC dose test

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What we will bring to DESY?

• ECAL module system, LED / temp. monitoring
  systems
• Trigger / veto counters
• Analysis server (CoreDuo 2.3GHz, 1GB RAM, 500GB
  HD)
• Laptops with X-window system (Does everyone have
  it?)
• Oscilloscopes
• Testers
• Source-meter, HPK amp ?
• Cables, connectors, test boards
• Tools (drivers, nippers, pliers, cutters, etc.)

Tell me if we need to put more items to the list.
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Schedule toward the SC-ECAL Beam Test _at_ DESY
Dec 2006
Jan 2007
Feb 2007
1
2
3
4
1
2
3
4
1
2
3
4
ACFA
KEK
Japan -Korea
Beam Test _at_ DESY Feb 25 Mar 29
Shipping Feb-14
Delivery of 400 MPPCs
Delivery of 360 MPPCs
Settle MPPC Operation voltage
Prepare MPPC mass check system
MPPC numbering Mass check
MPPC mass check.
MPPC soldering
MPPC baking and soldering
Direct-readout megastrip source scan
Test assembly Install LED/Temp. monitor
system Prepare shipping
megastrip Assembly source scan
Megastrip bench test
Fabrication of megastrip layer components
Finalize module design
Fabrication of Frame / light shielding structure
Establish LED / Temperature monitoring system
Prepare Trigger / Veto counters
MPPC study (response curve)
Analysis code / Event display
Contact DESY (DC gas, safety issue, etc)
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Summary

• The GLD ECAL beam test will be held at DESY
  during Feb 25 Mar 29 2007.
• The preparation is going well, but we still have
  lots of things to do.
• Schedule until the beam test is very tight !
• We will have an exciting experience at DESY!

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Backups
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Questions about KNU module

• How to put the module ?
• MPPC Gain monitoring ?
• Temperature monitoring ?
• Measurement plan ?

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Accomodation plan
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Scheme of the Readout Electronics
Baseboard (6 analog boards mounted, 6 board x 18
chan. 108 chan. )
To DAQ PC
FPCB
CRC board (in VME crate)
AHCAL module
GLD ECAL module
To Slow-control PC
HV supply (up to 100 V)
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Analog Board ASIC scheme
40kO
100MO
0.1pF
ASIC
2.4pF
8-bit DAC 0-5V
0.2pF
1.2pF
0.4pF
0.6pF
0.8pF
0.3pF
in
12kO
4kO
24pF
Rin 10kO
10pF
50O
12pF
8pF
4pF
2pF
1pF
6pF
100nF
3pF

• CR-RC² Shaper
• Variable time constant4 bits (12 to 180ns)
• 12ns ? photoelectron measurement (calibration
  mode)
• 180ns ? Mip measurement (physics mode)

• Charge Preamplifier
• Low noise 1300e- _at_40ns
• Variable gain
• 4bits 0.67 to 10 V/pC

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Gain of the ASIC Amp

• We have 2 different modes under current setting
• 1. Physics mode lower gain, large dynamic range
• Can not see the ped 1 p.e. peaks
  separation
• 2. Calibration mode high gain (x20 of physics
  mode)
• Can see the peak separation
• We can choose the mode for each individual run.
• Inter-calibration of the gain between these 2
  modes is necessary. Will be performed in MIP
  calibration run?
• We can choose some other gains if we request,
• though I think current setting for AHCAL is
  useful enough.

MIP calibration run (Each with phys. and calib.
mode)
Pedestal run (Each with phys. and calib. mode)
Beam run (Physics mode)
Pedestal run (Each with phys. and calib. mode)
MIP calibration run (Each with phys. and calib.
mode)
LED calibration run (Each with phys. and calib.
mode)


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Pedestal 1 p.e. Peaks Separation
(Calibration mode)
Coaxial 2 m
LED
Clear fiber
To HCAL baseboard
MPPC
Vbias V0 1.95 V
Vbias V0 2.95 V
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Dynamic range (Physics mode)
(20220-1123) / 226 19.1 1603 pixels
Vbias V0 2.95 V
Pedestal (1123 ADC counts)
Distance between pededestal 1p.e. In
Calibration mode
Saturated MPPC Signal (20220 ADC counts)
Ratio of Gains between calib. and physics mode
Dynamic range is enough for 1600 pixels !!
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Analysis scheme
Raw binary data
Detector geometry, alignment, mapping, etc
LCIO data
Database
User analysis modules
Marlin framework
Plots, Ntuples, .

• We need to request for database entry for our
  ECAL module
• Need to prepare codes for detector geometry,
  mapping.
• We also need to give a Prefix of our detector
  which is used as identifier in the analysis
  module (like AHCAL)
• I propose SCECAL (SCintillator ECAL) for the
  prefix.
• (e.g. our calibration constants will be named
  SCECAL_CALIB on database)

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Experts _at_ DESY

• Felix ... The head
• Erika ... Expert of everything in CALICE group
• Beni Expert of the AHCAL DAQ electronics and
  analysis
• contact person of the GLDCAL
  beam test at DESY
• Sebastian Expert of software package
• Niels Expert of AHCAL analysis code
• Nicola Expert of SiPM / MPPC
• Alexandra Expert of SiPM / MPPC

They are really nice, and of course, very
reliable !