Towards A Scintillator (Semi)-Digital Hadron Calorimeter: Progress at NIU/NICADD Jerry Blazey

Jerry Blazey Jerry Blazey NIU/NICADDNIU/NICADD

Towards A Scintillator Towards A Scintillator (Semi)-Digital Hadron (Semi)-Digital Hadron

Calorimeter: Progress at Calorimeter: Progress at NIU/NICADDNIU/NICADD

Jerry BlazeyJerry BlazeyNorthern Illinois UniversityNorthern Illinois University


LC Activities at NIU/NICADDLC Activities at NIU/NICADD Scintillator (Semi-)Digital Hadron Scintillator (Semi-)Digital Hadron

Calorimeter: Progress at NIU/NICADD Calorimeter: Progress at NIU/NICADD – This Talk– This Talk

Test Beam Plans for Scintillator Test Beam Plans for Scintillator Hadron Calorimeter & Tail-catcherHadron Calorimeter & Tail-catcher – – Vishnu Zutshi – This SessionVishnu Zutshi – This Session

G4-based Simulation Status & Plans – G4-based Simulation Status & Plans – Guilherme LimaGuilherme Lima – Session 7 Friday – Session 7 Friday 8:308:30

Muon Simulation Development & Muon Simulation Development & StatusStatus – Arthur Maciel – Muon/PID – Arthur Maciel – Muon/PID Session Wednesday 1:00Session Wednesday 1:00


““Generic” Calorimeter Simulations Generic” Calorimeter Simulations First Design & Prototype & Results First Design & Prototype & Results

on Sensitivity and Thresholdon Sensitivity and Threshold Optimization of Unit CellsOptimization of Unit Cells Light Sensor InvestigationsLight Sensor Investigations


A Generic Calorimeter:A Generic Calorimeter: Number of Cells vs. Pion Number of Cells vs. Pion

EnergyEnergy

For a 0.25 MIP threshold, # cells monotonicallyincreasing with energy for a wide range of cell sizes.

0.25mip threshold

# ofCells

E

100

20


Digital vs. AnalogDigital vs. Analog

Very similar correlations exist for hits or energy Between the EMCAL and HCAL

Energy 10,50 GeV Hits 10,50 GeV

Hits HCAL E HCAL

Hits ECAL E ECAL


Single Particle Energy Single Particle Energy ResolutionResolution

Minimize (EMinimize (Eoo--aaiiLLii))22

aaii calculated for 10 GeV & calculated for 10 GeV & applied to all E, conservativeapplied to all E, conservative

i=2 for EMCAL & HCAL, also i=2 for EMCAL & HCAL, also conservativeconservative


Single Particle Energy Single Particle Energy Resolution Resolution

Non-projective geometry

For lower energy particles digital approach has superior resolution!

/E

E

0.1

20


Resolution as a Function Resolution as a Function ofof

Multiple Thresholds or Multiple Thresholds or BitsBits

* As in the previous slide, below 20 GeV digital resolution superior to analog.*For E>10 GeV, more bits superior.

/E)dig

/E)analog

E

So it works for single particles how about jets?

1

2


Toy Simulation: Toy Simulation: “Recipe” for a Jet“Recipe” for a Jet

Determine resolution independent of algorithmDetermine resolution independent of algorithm For ZZ events PFor ZZ events PTT order stable MC particles, order stable MC particles,

ignore ignore ’s’s For charged hadrons assume perfect energy For charged hadrons assume perfect energy

(from tracker)(from tracker) Smear the energy of other particlesSmear the energy of other particles

– For neutral hadrons use resolutions for charge pions (just discussed). For neutral hadrons use resolutions for charge pions (just discussed). – For photons use For photons use ~ 17%/sqrt(E) ~ 17%/sqrt(E)

Start with highest pStart with highest pTT particle and cluster in 0.7 particle and cluster in 0.7 conecone

Repeat for remaining particlesRepeat for remaining particles Add individual energies to get jet energyAdd individual energies to get jet energy


ZZ Events: Sanity ChecksZZ Events: Sanity Checks

Stable MC particles

Energy Fractions

Neutral hadron fraction

fraction

~10%

~25%


Jet E ResolutionJet E Resolution

rms used

/E

Jet E(GeV)So the idea holds water: At all energies 3x3 single

threshold resolution comparable to analog!


Using full DHC E-flow: Jet Using full DHC E-flow: Jet EErecrec/E/Egengen

~60% better

(Vishnu Zutshi, ECFA-DESY Workshop, 4/1/2003http://nicadd.niu.edu, presentation 0046)

= 0.25 = 0.16

Calorimeter only Eflow


Full DHC Eflow: Jet EFull DHC Eflow: Jet Erecrec/E/Egengen

= 0.17 = 0.16

Eflow digital (2cm2 cells) Analog rather than hits

Digital approach not yet optimizedbut performance comparable to

analog!


Hardware Prototypes:Hardware Prototypes:Stack, Layer, & Unit CellStack, Layer, & Unit Cell

WLS to Clear Fiber MPTM


Cosmic Data with PMT Cosmic Data with PMT ReadoutReadout

~11 p.e. peak = 1MIP

ADCADCADCADC


Efficiency and Noise Rejection

0%

20%

40%

60%

80%

100%

120%

Number of MIPs

Perc

ent

EfficiencyNoise Rejection

0.25 MIP threshold: efficient, quiet


Cell Response Uniformity Cell Response Uniformity & Dispersion& Dispersion

0

0.2

0.4

0.6

0.8

1

1.2

0 10 20 30 40 50POSITION OF Sr-90, MM

NO

MA

LIZE

D R

ESPO

NSE

Column1Column1

MeanMean 1562.5061562.506

Standard ErrorStandard Error 24.5264724.52647

MedianMedian 1557.961557.96

ModeMode #N/A#N/A

Standard DeviationStandard Deviation 115.0394115.0394

Sample VarianceSample Variance 13234.0513234.05

KurtosisKurtosis -0.05291-0.05291

SkewnessSkewness 0.3349390.334939

RangeRange 444.52444.52

MinimumMinimum 1386.471386.47

MaximumMaximum 1830.991830.99

SumSum 34375.1434375.14

CountCount 2222

Cell-to-cell ~ 7%(dominated by fiber)Uniformity ~ 3%


Other Uniformity Other Uniformity MeasurementsMeasurements

-0.200

0.000

0.200

0.400

0.600

0.800

1.000

1.200

0 10 20 30 40 50

POSITION OF THE Sr-90, MM

NORM

ALIZ

ED R

ESPO

NSE

0.000

0.200

0.400

0.600

0.800

1.000

1.200

0 10 20 30 40 50 60

POSITION OF THE Sr-90, MM

NORM

ALIZ

ED R

ESPO

NSE


Absolute Response Absolute Response MeasurementsMeasurements

(Purple: Cast, Blue: Extruded)(Purple: Cast, Blue: Extruded)CellCell GrooveGroove AreaArea ResponseResponseHexagonHexagon SigmaSigma 9.49.4 1895.31895.3SquareSquare SigmaSigma 9.49.4 1665.81665.8SquareSquare SigmaSigma 66 1740.51740.5HexagonHexagon SigmaSigma 66 1743.81743.8HexagonHexagon SigmaSigma 9.49.4 2015.92015.9SquareSquare StraightStraight 9.49.4 1523.41523.4SquareSquare StraightStraight 44 1618.61618.6SquareSquare StraightStraight 9.49.4 861.5861.5HexagonHexagon StraightStraight 9.49.4 900.9900.9HexagonHexagon SigmaSigma 9.49.4 1089.41089.4

Since light ample, can optimize for ease of construction


Surface Surface Treatment/WrappingTreatment/Wrapping

TyvekTyvek PaintPaint VM 2002VM 2002 MylarMylar CM590CM590 CM500CM500 Alum FoilAlum Foil

1.001.00 0.890.89 1.081.08 0.830.83 0.280.28 0.440.44 0.630.63

UNPOLISHED TOP ANDUNPOLISHED TOP ANDPOLISHED BOTTOMPOLISHED BOTTOM

POLISHED TOP ANDPOLISHED TOP ANDPOLISHED BOTTOMPOLISHED BOTTOM

UNPOLISHED TOP ANDUNPOLISHED TOP ANDUNPOLISHED BOTTOMUNPOLISHED BOTTOM

0.980.98 1.001.00 1.021.02

Paint easy, little light lossPaint easy, little light loss


Miscellaneous Miscellaneous Measurements:Measurements:

source, glues, fiberssource, glues, fibers Extruded/CastExtruded/Cast

0.70.7

After/Before glueAfter/Before glue EJ500/BC600EJ500/BC600 (optical glues)(optical glues)

Y11/BCF92Y11/BCF92

1.151.15 1.01.0 3.13.1

Extruded scintillatorExtruded scintillator

1mm round Kuraray

0.8 mm square Bicron

Fiber has greatest affect on yield.Fiber has greatest affect on yield.


NICADD/Fermilab NICADD/Fermilab ExtruderExtruder


Thickness Tolerance: 2-3%Thickness Tolerance: 2-3%Response Depends weakly on Response Depends weakly on

Thickness: ~20%/mmThickness: ~20%/mmNORMALIZED CELL RESPONSE OF Cs-137

y = 0.8426x + 0.1376R2 = 0.9852

0.75

0.95

1.15

1.35

1.55

1.75

0.75 0.95 1.15 1.35 1.55 1.75

CELL THICKNESS NORMALIZED TO 3 MM

RES

PON

SE N

OR

MA

LIZE

D T

O 3

MM

CEL

L

3mm

4mm

5 mmExtruded Tile

4.78

4.8

4.82

4.84

4.86

4.88

4.9

4.92

1 2 3 4 5 6

Position in 20 cm steps

Thickn

ess in m

m Side oneSide two

Thickness not an issue


Optimum CellOptimum Cell Hexagonal or SquareHexagonal or Square 4 - 9 cm4 - 9 cm22

Straight GrooveStraight Groove High yield fiberHigh yield fiber Glued Fiber and Painted SurfaceGlued Fiber and Painted Surface Extruded (cut costs) @ 5mmExtruded (cut costs) @ 5mm

But a bigger question is the light sensor: But a bigger question is the light sensor: PMTs costly, bulkyPMTs costly, bulky

we have been investigating APDs, MRS, Si-PM…we have been investigating APDs, MRS, Si-PM…

My currentguess…


Hamamatsu Avalanche Hamamatsu Avalanche Photo-DiodesPhoto-Diodes

Gain for Hamamatsu APD for different light wavelengths at 18 ºC

1.0

10.0

100.0

1000.0

100 150 200 250 300 350 400

Bias Voltage, V

Gai

n

486nm 565nm for 587nm 660nm


Cosmic MIP with Cosmic MIP with Avalanche Avalanche

Photo-DiodePhoto-Diode

Hamamatsu S8550


Metallic ResistiveMetallic ResistiveSemiconductor Semiconductor

(CPTA*) (CPTA*)

LED signal

0

200

400

600

800

1000

1200

1

33 65 97

129

161

193

225

257

289

321

353

385

417

449

481

513

ADC counts

Even

ts

Representative Spectrum

*Center for Perspective Technologies and Apparatus


Cosmics with MRSCosmics with MRS

Range of working points

y = 24.255x - 1180.5R2 = 0.9969

0

10

20

30

40

50

60

49.8 50 50.2 50.4 50.6 50.8 51

Bias Voltage (V)

Ave

rage

min

us

pede

stal

~5 PE

5050 515100

6060


Si-PMs (PULSAR/MEPHI*) Si-PMs (PULSAR/MEPHI*) mounted on cell?mounted on cell?

Ru106, Si-PMT, 51 Volts, ~6 PE

0

100

200

300

400

500

600

700

800

900

1000

1 56 111 166 221 276 331 386 441 496 551 606 661 716 771 826 881 936A D C C HA N N EL

MEPHI sample, Courtesy of B.Dolgoshein

Representative Spectrum

*Moscow Engineering Physics Institute


Cosmic Data with Si-PMCosmic Data with Si-PMN

umbe

r of P

.E.

Comparable to PMTComparable to PMT


Tabulated Specs/StudiesTabulated Specs/StudiesDevice HAMAMATSU

APD VLPC SiPM or

MRS PMT

Photo Electrons/ MIP

>30 (by specs)

>30 >>1100 >>1100

Gain 400 ? 10E(5) 10E(6) 10E(6) APD output Charge (fC)

3

768

1152

1152

S/N(room T)

~ 5.5 Est. ~ 3 real ~ 8.1 (10oC)

>10 (9K) meas. *

~ 8meas.** > 10 meas.***

* A. Bross et al., Fermilab FN-0733, 2003* A. Bross et al., Fermilab FN-0733, 2003** B. Dolgoshein, “An Advanced Study of Silicon PM”, ICFA ** B. Dolgoshein, “An Advanced Study of Silicon PM”, ICFA IB, 2002IB, 2002*** V. Rykalin, NICADD presentation, *** V. Rykalin, NICADD presentation, http://nicadd.niu.eduhttp://nicadd.niu.edu , , 20022002

Estimate <$10 channel in bulk for Extruded/SiPMEstimate <$10 channel in bulk for Extruded/SiPM


Scintillator DHC Scintillator DHC ConclusionsConclusions

Simulations indicate approach competitive Simulations indicate approach competitive with analog calorimetrywith analog calorimetry

Prototypes indicate there is sufficient Prototypes indicate there is sufficient sensitivity (light x efficiency) & uniformity.sensitivity (light x efficiency) & uniformity.

Now optimizing materials & construction to Now optimizing materials & construction to minimize cost with required sensitivityminimize cost with required sensitivity

SiPM and MRS look very promisingSiPM and MRS look very promising

All-in-all looks like a competitive option….All-in-all looks like a competitive option….We’ll be moving towards the next prototypeWe’ll be moving towards the next prototype

Documents

Towards A Scintillator (Semi)-Digital Hadron Calorimeter: Progress at NIU/NICADD Jerry Blazey