1. HCAL task status report
Felix Sefkow
EUDET Annual Meeting
Oct 10, 2007

2. Calibration electronics Detector optimization
Overview
Goal: A compact and realistic (i.e. scaleable) scintillator HCAL structure with embedded electronics
Electronics
integration
Mechanics
Scintillator
Photo-sensors
Calibration electronics
Calibration studies
Test beam
Detector integration
Detector optimization
EUDET Infrastructure
FEE
DAQ
HCAL task
Felix Sefkow Oct 10, 2007

3. All dimensions are preliminary TILE MGPD
Chemically treated edges for light reflection Ø
Schedule OK:
Tiles for electronics unit in 2008
For complete layer / small test stack in 2009
MGPD
2.54
Ø=?
0.6
556 cells, Ø1mm
CPTA, Moscow
0.8
2.7
4.0
M.Danilov, ITEP

4. MGPD PROPERTIES OK for WLS readout; direct coupling
studied in parallel
M.Danilov
HCAL task
Felix Sefkow Oct 10, 2007

5. Test beam Not part of EUDET, but has impact:
Feedback to detector concept and calibration methods
Availability of human resources
June 2007: all HCAL active layers completed (8000 SiPMs)
Movable stage completed, fully functional
HCAL task
Felix Sefkow Oct 10, 2007

6. Example: temp. dependence of gain for 5000 channels
Test beam calibration
Calibration is done with MIPs (muons)
To be established for ILC: simulations
Monitoring with
Temperature sensors
LED reference pulses (problematic)
Direct observation of SiPM gain
Calibration electronics developed and built in Prague
Redundancy for cross-checks
Large dynamic range
Calibration data analysis: DESY, Bergen
Tools for multi-channel studies developed
S.Schaetzel, DESY
Example: temp. dependence of gain for 5000 channels
HCAL task
Felix Sefkow Oct 10, 2007

7. Saturation Curves for Module 13, 5-6
Compare 4 runs from August & October
Saturation curve after pedestal subtraction, PIN & gain correction
SiPM non-linearity
- Does in-situ meas. agree with test bench?
Is it stable?
First results encouraging, but analysis ongoing
Saturation curve after adjustment to common origin with slope one
G.Eigen, Bergen
 August runs
 October runs
G. Eigen,HCAL task Paris,
Felix Sefkow Oct 10, 2007

8. Calibration system approaches
Optical signal distribution
central pulser (one or few per layer)
Minimized cross-talk to readout (photo-sensors and FEE)
Monitoring of light source stability for reference possible
Most frequently made choice, experience
Electrical signal distribution
Many pulsers, one per single or few channels
Avoids optical coupling problems (stability, uniformity)
Can work with very small electrical and optical pulses
Not yet tried until now
HCAL task
Felix Sefkow Oct 10, 2007

9. QR LED driver Development at IoP, Prague
Quasi-resonant circuit: minimize electromagnetic interference
I.Polak, Prague
Wavefrom and Xtalk OK
2 channel PCB in month 22
LED
PIN
HCAL task
Felix Sefkow Oct 10, 2007

10. LED on board Proof-of-principle, check for cross-talk, uniformity
Test also
Different driver schematics
Small connector
SiPM coupling
M.Reinecke, DESY
HCAL task
Felix Sefkow Oct 10, 2007

11. Ongoing optimization and measurements (ligt uniformity, dyn. range,…)
Estimate Crosstalk
Scope in averaging
mode
Light in Tile 1
≈40mV
Crosstalk to
tile 2 and tile 4
≈1mV
Very encouraging
Ongoing optimization and measurements
(ligt uniformity, dyn. range,…)
Crosstalk ≈ 2.5%
electr./optical ??
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
EUDET annual meeting – Paris
Oct. 2007

12. Integrated layer design
Sector
wall
Reflector Foil
100µm
Polyimide Foil
PCB
800µm
Bolt with inner
M3 thread
welded to bottom
plate
SiPM
Tile
3mm
HBU Interface
500µm gap
Bottom Plate
600µm
ASIC
TQFP-100
1mm high
Top Plate
600µm steel
Component Area:
900µm high
HBU height:
6.1mm
(4.9mm without covers => absorber)
Absorber
Plates
(steel)
Spacer
1.7mm
fixing
DESY
integrated
HCAL task
Felix Sefkow Oct 10, 2007

13. HBU – PCB Layer Structure
6 layer design with cut-outs for ASICS and connectors
75W Lines for high-gain SiPM setup
Two signal layers for impedance-controlled routing
Total height (PCB + components): 1.5mm
Two companies agreed on structure at reasonable costs!!
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
EUDET annual meeting – Paris
Oct. 2007

14. EUDET annual meeting – Paris
Slabs of an AHCAL layer
AHCAL slab
12x12 tiles
HBU:
Number of channels
per layer not constant!
9x12 tiles
24 SPIROCs in chain
6 HBUs in a row
Two flexleads for
interconnection
Slow-Control and
Readout token
to LDA
DIF-DIF conn.
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
EUDET annual meeting – Paris
Oct. 2007

15. HEB Interconnection Concept
Flexlead and 80-pin connector
Interconnection to AHCAL-
Layer (HBU)
POWER CALIB DIF
DIF-DIF conn.
Redundancy against
failures of LDA
HLD
Changes Size from
Layer to layer
HEB
Same Size for all
38 AHCAL layers
To LDA
DIF - Detector Interface (Configuration and Operation)
CALIB - Light and/or Charge calibration and monitoring
POWER – Layer power and temperature monitors
Mezzanine setup allows independent development of different groups.
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
EUDET annual meeting – Paris
Oct. 2007

16. AHCAL Half Sector - Integration
AHCAL Slab
6 HBUs in a row
HBU
HCAL Base Unit
typ. 12 x 12 tiles
SPIROC
typ. 4 on a HBU
HEB
HCAL Endcap Board
Hosts mezzanine modules:
DIF, CALIB and POWER
HLD
HCAL Layer Distributor
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
EUDET annual meeting – Paris
Oct. 2007

17. Temperature / Power Dissipation
From P. Göttlicher (DESY)
No. channels: 1100 / m²
Pow. Diss.: 40µW / channel
(25µW ASIC, 15µW HV,
3A / layer during bunch train)
Time constant of heat effects:
a = 6 days
Temperature at far end (DT):
DT ≈ 0.3 °C
Power pulsing and a good thermal connection (cooling)
enables a stable operation!
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
LCWS 2007 – DESY Hamburg

18. POWER to AHCAL layer For 1V in 2ms: 3.4mF 10 SMD tantal
Components on HEB, HLD
For 1V in 2ms:
3.4mF
10 SMD tantal
For 5mV in 1µs:
340µF
40 large ceramic
‚Slow‘
‚Fast‘
P. Göttlicher, DESY
HCAL task
Felix Sefkow Oct 10, 2007

19. Testboard II : ASIC + Integration
SPIROC Testboard (HBU prototype):
Assembly (Tiles, PCB, ASICs, LEDs), Cassette Construction
Performance in the dense HBU setup:
Noise, gain, crosstalk, power and signal integrity
DAQ Interface
LCS with LEDs on board.
Tile integration to HBU : see M. Danilov‘s talk (alignment pins)
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
EUDET annual meeting – Paris
Oct. 2007

20. Testboard III : Power-System
Test Power-Ground System (2.20m):
Oscillations when switching?
Voltage drop, signal integrity
(traces, connectors)?
SPIROC far end
(blocking caps sufficient)?
‚Layer
Concentrator‘
(DIF*)
Extenders
(Power-Gnd, Traces)
SPIROC
Testboard
HCAL task
Felix Sefkow Oct 10, 2007
Mathias Reinecke
EUDET annual meeting – Paris
Oct. 2007

21. Mechanical design Engineering resources: Cassette: Absorber structure:
EUDET position filled as of Oct 1st, 2007
Increasing support at DESY after end of HERA and completion of CALICE test beam set-up
Cassette:
Evolve testbeam prototype design
Absorber structure:
Start re-evaluation of TESLA design
HCAL task
Felix Sefkow Oct 10, 2007

22. Milestones and Deliverables
reports
Concepts,
designs –
and final
prototypes
concepts
designs
VME test stand
construction
PPT construction
Testbeam data taking
feedback
HCAL task
Felix Sefkow Oct 10, 2007

23. Conclusion Things are starting to fall into place
A nice concept is emerging – looking forward to the design phase
The HCAL task is on track
HCAL task
Felix Sefkow Oct 10, 2007