d. attié

Nov. 11, 2009WP meeting 94

1

D. Attié

SINP, January 22th, 2010

i r f u

yalcas

i r f u

yalcas

Beam testsBeam tests

of a Micromegasof a Micromegas

Large TPC PrototypeLarge TPC Prototype

OverviewOverviewOverviewOverview

[email protected] 2

Introduction, technological choice for ILC-TPC

•The Large TPC Prototype for ILC

•Bulk Micromegas with resistive anodes

•Beam test conditions, T2K electronics

•Data analysis results:– Drift velocity

– Pad response function

– Resolution

•Comparison between two resistive modules

•Future plans:– Pixelized Micromegas module

– Integrated electronics for 7 modules

Conclusion

SINP seminar ̶ January 22th, 2010

2. Spread charge over several pads: resistive anode+ reduce number of channels, cost and budget+ protect the electronics– limit the track separation– need offline computing

How to improve the spatial resolution?How to improve the spatial resolution?How to improve the spatial resolution?How to improve the spatial resolution?

3SINP seminar ̶ January 22th, 2010

• Need for ILC: measure 200 track points with a transverse resolution ~ 100 μm

- example of track separation with 1 mm x 6 mm pad size: 1,2 × 106 channels of electronics sz=0 > 250 μm amplification avalanche over one pad

• Spatial resolution σxy:

- limited by the pad size (s0 ~ width/√12)

- charge distribution narrow (RMSavalanche ~ 15 μm)

1. Decrease the pad size: narrowed strips, pixels+ single electron efficiency – need to identify the electron clusters

2. Resistive anode

Calculation for the ILC-TPC

D.C. Arogancia et al., NIMA 602 (2009) 403

55 mm

1. Pixels

[email protected]

Large TPC Prototype for ILCLarge TPC Prototype for ILCLarge TPC Prototype for ILCLarge TPC Prototype for ILC

[email protected] 4SINP seminar ̶ January 22th, 2010

• Built by the collaboration LC-

TPC

• Financed by EUDET

• Located at DESY: 6 GeV e-

beam

• Sharing out :- magnet: KEK, Japan

- field cage: DESY, Germany

- trigger: Saclay, France

- endplate: Cornell, USA

- Si envelope: OAW, Austria

- laser: Victoria U., Canada

- Micromegas: Saclay, France, Carleton/Montreal U.,

Canada

- GEM: Saga, Japan

- TimePix pixel: F, G, NL



• 60 cm long TPC• Endplate ø = 80 cm of 7 interchangeable panels

of 23 cm to fit in 1T superconducting magnet

24 rows x 72 columns <pad size> ~ 3x7

mm2

80 cm

Module presently avalaibleModule presently avalaibleModule presently avalaibleModule presently avalaible


Resistive ink~1 MΩ/□

Resistive Kapton~4 MΩ/□

Standard

2 Resistive Kapton~1 MΩ/□

Beam test conditions at B=1TBeam test conditions at B=1TBeam test conditions at B=1TBeam test conditions at B=1T


• Bulk Micromegas detector: 1726 (24x72) pads of ~3x7 mm²

• AFTER-based electronics (72 channels/chip): – low-noise (700 e-) pre-amplifier-shaper– 100 ns to 2 μs tunable peaking time– full wave sampling by SCA

• Beam data (5 GeV electrons) were taken at several z values by sliding the TPC in the magnet. Beam size was 4 mm rms.

– frequency tunable from 1 to 100 MHz (most data at 25 MHz)

– 12 bit ADC (rms pedestals 4 to 6 channels)

6 FECs and 1 FEM in its shielding

Determination of z rangeDetermination of z rangeDetermination of z rangeDetermination of z range


• Cosmic run at 25 MHz of sampling frequency time bin = 40 ns

• Drift velocity in T2K gas (Ar/CF4/iso-C4H10, 95/3/2) at 230 V/cm:

• TPC length = 56.7 cm agreement with survey

220 time bins

Pad signals: beam data samplePad signals: beam data samplePad signals: beam data samplePad signals: beam data sample


• RUN 284

• B = 1T

• T2K gas

• Peaking time: 100 ns

• Frequency: 25 MHz

Two-track separationTwo-track separationTwo-track separationTwo-track separation


r

φ

z

Drift velocity measurementDrift velocity measurementDrift velocity measurementDrift velocity measurement


• Measured drift velocity (Edrift = 230 V/cm, 1002 mbar): 7.56 ±

0.02 cm/s

• Magboltz: 7.548 ± 0.003 cm/s in Ar/CF4/iso-C4H10/H2O

(95:3:2:100ppm)

B = 0T

Determination of the Pad Response FunctionDetermination of the Pad Response FunctionDetermination of the Pad Response FunctionDetermination of the Pad Response Function


• Fraction of the row charge on a pad vs xpad – xtrack

(normalized to central pad charge)

Clearly shows charge spreadingover 2-3 pads(data with 500 ns shaping)

• Then fit x(cluster) using thisshape with a χ² fit, and fit simultaneously all lines

xpad – xtrack (mm)

Pad pitch

See Madhu Dixit’s talk

xpad – xtrack

(mm)

Spatial resolutionSpatial resolutionSpatial resolutionSpatial resolution


• Resolution at z=0: σ0 = 54.8±1.6 m with 2.7-3.2 mm pads (wpad/55)

• Effective number of electrons: Neff = 31.81.4 consistent with expectations

eff

dx N

zC

22

0

Field distortion measurement using laser Field distortion measurement using laser Field distortion measurement using laser Field distortion measurement using laser


Beam position

5 cm

• Two laser devices installed on the endplate to light up photosensitive patternon the cathode (spots and line)

• Deterioration of resolution at z > 40 cm : due to low field 0.9 to 0.7 T in the last 20 cm (significant increase of transverse diffusion)

30 cm50 cm

B field map of the magnetPhotoelectrons from the cathode pattern

Description of the resistive anodesDescription of the resistive anodesDescription of the resistive anodesDescription of the resistive anodes


DetectorDielectric

layerResistive layer

Resistivity (MΩ/□)

Resistive Kapton

Epoxy-glass75 μm

C-loaded Kapton25 μm

~4-8

Resistive Ink Epoxy-glass 75 μm

Ink (3 layers) ~50 μm

~1-2

Resistive Kapton Resistive Ink

PCB

PrepregResistive Kapton

PCB

Prepreg

Resistive Ink

Comparison at B=1T, z ~ 5 cmComparison at B=1T, z ~ 5 cmComparison at B=1T, z ~ 5 cmComparison at B=1T, z ~ 5 cm



• RUN 310

• Vdrift = 230 cm/s

• Vmesh = 380 V

• Peaking time: 500 ns• Frequency Sampling: 25 MHz

• RUN 549

• Vdrift = 230 cm/s

• Vmesh = 360 V

• Peaking time: 500 ns • Frequency Sampling: 25 MHz

Pad Response Functions, z ~ 5 cmPad Response Functions, z ~ 5 cmPad Response Functions, z ~ 5 cmPad Response Functions, z ~ 5 cm



Γ² = 7 mm

δ = 10 mm

Γ² = 11 mm

δ = 13 mm

xpad – xtrack

(mm)

xpad – xtrack

(mm)

σz=5 cm = 68 µm σz=5cm = 130 µm !

44

22

44

22

1

1)(

xbxb

xaxaxf

xpad – xtrack

(mm)

xpad – xtrack

(mm)

2.2 GeV Momentum2.2 GeV Momentum2.2 GeV Momentum2.2 GeV Momentum


• B=1T

• Beam energy set to 2.2 GeV using one module in the center

• Simple Landau fit MPV = 2.2 GeV

Tests with Si envelope (nov. 2009) Tests with Si envelope (nov. 2009) Tests with Si envelope (nov. 2009) Tests with Si envelope (nov. 2009)


Si

Si

From Vienna

Synchronized events with Si envelopeSynchronized events with Si envelopeSynchronized events with Si envelopeSynchronized events with Si envelope


TLU

Resistive Ink

Resistive Kapton

Description of the TimePix chipDescription of the TimePix chipDescription of the TimePix chipDescription of the TimePix chip


• Chip (CMOS ASIC) upgraded in the EUDET framework from the Medipix chip developed first for medical applications

• IBM technology 0.25 m

• Characteristics:– surface: 1.4 x 1.6 cm2

– matrix of 256 x 256– pixel size: 55 x 55 μm2

• For each pixel:– preamp/shaper– threshold discriminator– register for configuration– TimePix synchronization logic– 14-bit counter

• Noise: ~ 650 e-– Cin ~ 15 fF

55 m

55 m

Pixel

14111 m

1612

0 m

1408

0 m

(pi

xel a

rray

)

11 22 33

44

55

55

μ m

55 μ m

Pre

am

p/

shap

er

TH

L dis

c.

Con

fig

ura

tion

la

tch

es

Interface

Counter

Syn

chro

niz

ati

on L

ogic

TimePix synchronization logic controlTimePix synchronization logic controlTimePix synchronization logic controlTimePix synchronization logic control


Medipix Mode

Timepix Mode

Mask

P1 P0 Mode

0 0 0 Masked

0 0 1 Masked

0 1 0 Masked

0 1 1 Masked

1 0 0 Medipix

1 0 1 TOT

1 1 0 Timepix-1hit

1 1 1 Timepix

• Each pixel can be configured independently in 5 different modes

• Internal clock up to 100 MHz

Charge summed

not detected

detected

100 MHz

Analog signal

Internal shutter

Shutter

Internal clock

Digital signal

10 ns

Micro-TPCMicro-TPC TimePix/Micromegas TimePix/MicromegasMicro-TPCMicro-TPC TimePix/Micromegas TimePix/Micromegas


Field cage

Cover

Micromegasmesh

TimePix chip

Windows for X-ray sources

Windows for β sources

6 c

m• Micro-TPC with a 6 cm height field cage

• Size : 4 cm × 5 cm × 8 cm

• Read out by MUROS or USB1.2 devices

• Two detectors are available now at Saclay

Micro-TPCMicro-TPC TimePix/Micromegas: Time mode TimePix/Micromegas: Time modeMicro-TPCMicro-TPC TimePix/Micromegas: Time mode TimePix/Micromegas: Time mode


• TimePix chip+ SiProt 20 μm+ Micromegas

• 55Fe source

• Ar/Iso (95:5)

• Time mode

• z = 25 mm

• Vmesh = -340 V

• tshutter = 283 μs

Micro-TPCMicro-TPC TimePix/Micromegas: Time mode TimePix/Micromegas: Time modeMicro-TPCMicro-TPC TimePix/Micromegas: Time mode TimePix/Micromegas: Time mode


• TimePix chip+ SiProt 20 μm+ Micromegas

• 90Sr source

• Ar/Iso (95:5)

• Time mode

• z ~ 40 mm

• Vmesh = -340 V

• tshutter = 180 μs

2×4 TimePix/InGrid matrix module2×4 TimePix/InGrid matrix module2×4 TimePix/InGrid matrix module2×4 TimePix/InGrid matrix module


• Mother card• Mezzanine card• Guard ring card• Heat dissipation block

Further tests for resistive bulk MicromegasFurther tests for resistive bulk MicromegasFurther tests for resistive bulk MicromegasFurther tests for resistive bulk Micromegas


In 2008/2009 with one detector module In 2010/2011 with 7 detector modules

Reduce

th

e e

lect

ronic

s to

fit

to t

he m

odu

le a

nd p

ow

er

con

sum

pti

on

Resi

stiv

e t

ech

nolo

gy c

hoic

e

7-modules project7-modules project7-modules project7-modules project


PCB detector (bottom)

FEM

FEC

• Remove packaging and protection diodes• Use 2 × 300 pins connector• Replace resistors SMC 0603 by 0402 (1 mm × 0.5 mm)



25 cm

14 cm

0,78 cm

0,74 cm

4,5 cm

12,5 cm

2,8 cm3,5 cm

3,5 cm

FEC

Chip

ConclusionsConclusionsConclusionsConclusions


•Three Micromegas technologies with resistive anode have been tested within the EUDET facility using 1T magnet to reduce the transverse diffusion

•C-loaded Katpon (4 MΩ/□) technology gives better results than resistive ink technology

•Data analysis results confirm excellent resolution at small distance with theresistive C-loaded Kapton (4 MΩ/□): 55 m for 3 mm pads

•Data analysis of laser tests and the second resistive C-loaded Kapton (1 MΩ/□) should be done soon.

•Plans are to test several resistive layer manufacturing process and capacitance/resistivity, then go to 7 modules with integrated electronics by the end of this year


Dhanyavad

Backup slidesBackup slidesBackup slidesBackup slides


TimePix chip architectureTimePix chip architectureTimePix chip architectureTimePix chip architecture

IO

Logic

LVDS

In

LVDS

Out32-bit CMOS Output

256-bit Fast Shift Register

3584

-bit

Pix

el C

olum

n-0

3584

-bit

Pix

el C

olum

n-0

Bandgap + 13 DACs16

120

m

14111 m35

84-b

it P

ixel

Col

umn

-135

84-b

it P

ixel

Col

umn

-1

3584

-bit

Pix

el C

olum

n-2

5535

84-b

it P

ixel

Col

umn

-255

1408

0 m

(pix

el a

rray

)

• Clock per pixel up to 100 MHz

• Characteristics:– analog power: 440 mW– digital power (Ref_Clk = 80 MHz): 450 mW– serial readout (@ 100 MHz): 9.17 ms– parallel readout (@ 100 MHz): 287 μs– > 36 M transistors on 6 layers

• Pixel modes:– masked– counting mode (Medipix, Timepix-1h)– Time-Over-Threshold “charge” info– Common stop “time” info


TimePix chip schematicTimePix chip schematicTimePix chip schematicTimePix chip schematic

Preamp

Disc

THR14 bitsShift Register

Input

Ctest

Testbit

Test Input

Mask

4 bits thr Adj

Mux

Mux

Clk_Read

Previous Pixel

Next Pixel

Conf

8 bits configuration

Polarity

Analogic part Digital part

Ref_Clk

Timepix SynchronizationLogic

Ref_Clkb

P0

P1

Shutter

Ovf Control

Clk_Read

Shutter_int

For each pixel


Readout system for Medipix/TimePix chipReadout system for Medipix/TimePix chipReadout system for Medipix/TimePix chipReadout system for Medipix/TimePix chip

• MUROSv2.1:

– Serial readout– VHDCI cable of length <3m– read 8 chips in mosaic– tunable clock [30-200MHz]– ~40fps @160MHz

http://www.nikhef.nl/pub/experiments/medipix/muros.html

• USB:

– Serial readout– ~5 fps@20MHz

http://www.utef.cvut.cz/medipix/usb/usb.html

• Mosaic achitecture:


Detectors using Medipix2/TimePix chipDetectors using Medipix2/TimePix chipDetectors using Medipix2/TimePix chipDetectors using Medipix2/TimePix chip

+

-

+

-

+

-

Medipix2 chip Medipix2/TimePix chip

X-ray source

Ionizing

particle

Single pixel

readout cell

Flip-chip bump bondingconnections

Semiconductorsensor

Gas volume

Amplification System (MPGD)

Drift grid

Solid detector Gas detectorx, y, F(x, y) x, y, z(t), E(x,y)


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