report from trd workshop trento, march 3-4 results from test beam analyses tr–production and...

Report from TRD WorkshopTrento, March 3-4

results from test beam analysesTR–production and X-ray absorption

measurementsgas properties recent advances of the read out electronicsprogress on DCS and services super-module design and integration status of chamber production software statusplanning

Hannes Wessels, Univ. Muenster

Test Beam Setup at T10

measurements w/omagnetic field

measurements withmagnetic field

Test Beam Setup Setup with 4 small chambers and a prototype of

the largest TRD chamber (1200x1600mm2) (DC5)

Cleanliness of e/ Separation

with coincidencesof the two Cherenkovcounters-> contaminationof e in and viceversa smaller than1/1000

V. Yurevich, A. Andronic

Performance of Various Radiators

-> no significant momentum dependence of -rejection

A. Andronic

Charge Distributions

-> distributions well described at fixed momenta-> possible effect of Bremsstrahlung visible

A. Andronic

e/ – Performance by Layer

-> performance of individual layers almost identical-> slight improvement with depth (Bremsstrahlung)-> slightly worse performance for large prototype (S/N)

A. Andronic

Independence of Efficiencies

-> efficiencies for pion identification of the different layers factorize

-> layer 5 slightly worse due to different S/N

A. Andronic

Influence of Material in Front of TRD

-> performance of the different layers with (triangles) and w/o (circles) material in front of the radiator

-> 8mm Al -> X/X0~9%

-> 10cm in front of DC1

-> small impact at very low momenta

A. Andronic

Influence of Material on Resolution

-> B=0-> no effect on resolution for pions-> small effect for e

O. Busch

Influence of Material on Resolution

-> B=0, 0.28, 0.42, 0.56 T

-> no change in resolution for pions

-> electrons somewhat affected as depth increases because Bremsstrahlung is produced before dipole

O. Busch

Position and Angular Resolution

-> no deterioration of resolution in magnetic field

-> slight decrease in angular resolution for large angles -> space charge effects

O. Busch

Lorentz Angle Measurements

-> good agreement of data and simulation to the level that CO2

contents variation, drift velocity, and alignment are understood

O. Busch

TR Measurements

-> beam is deflected from TR photon by B-field

O. Busch

Energy and Multiplicity of TR Photons

-> TR energy spectrum well understood-> measured multiplicity lower than simulated ~0.85

O. Busch

X-Ray Absorption Measurements

Setup at MPI Heidelberg

R. Schicker, T. Lehmann

Measurements of Radiator Materials

-> actual radiator less than 50% transparency for ETR < 6keV

R. Schicker, T. Lehmann

Gas Property Measurements

using mini-drift chamber establish procedure of known

mixtures (Ar/CO2, Ar/CH4) then test Xe-based mixtures (Xe/CO2, Xe/CH4)

G. Tsiledakis, C. Garabatos

l=2.25 cm

d=3.15 cm

Slit1 Slit2

90Sr (-source)

drift region

pads A KScintillator (trigger) phototube

drift electrode

Ua=1.5 kV

Ud=-1 kV -1.3 -1.6 : : -3.7

t1 t2

t=t2-t1

E=Ud/d (kV/cm) /p(bar)

u=l/t (cm/s)

Drift velocity measurements small DC

gas-mixturepads along pads

across pads


pad number

Drift time (s)

PH

(m

V/0

.74 )

Ar-CO2 (23%) gas mixture

E (kV/cm)

Dri

ft v

eloc

ity

(cm

/s)

GARFIELD

along pads

across pads

Why 23% CO2? New calibration of the flow meters

Test of the method shows agreement with GARFIELD

All next measurements “across pads”


Ar-CH4 (10%) gas mixture

E (kV/cm)

Dri

ft v

eloc

ity

(cm

/s)

GARFIELD

MIT measurements

2nd GSI measurements

1st GSI measurements

First runUse of a premixed gas mixture shows a discrepancy with GARFIELD and MIT .Second runRe-mixing on our own after a new calibration.Confirms MIT measurements, GARFIELD, our calibration and our method.


Xe-CH4 (10%) gas mixture

E (kV/cm)

Dri

ft v

eloc

ity

(cm

/s)

GARFIELD

MIT Christophorou

GSI

Disagreement with Garfield and measured data!


Xe-CO2 (15.4%) gas mixture

GARFIELD

GSI

Disagreement with Garfield

Dri

ft v

eloc

ity

(cm

/s)

E (kV/cm)


Xe-CO2 (20.5%) gas mixture

GARFIELD

GSI

Disagreement with Garfield

Dri

ft v

eloc

ity

(cm

/s)

E (kV/cm)

-> need certainty about gas composition

-> multiple scattering in Xe larger?

-> existing data insufficient

-> need measurements with controlled nitrogen contamination


Gas system statusGas system statusC. Garabatos, GSIC. Garabatos, GSI

• stability of pressurestability of pressure• NN22 separation separation• membrane testmembrane test

Stability of detector pressure

-0.5 -0.4 -0.3 -0.2 -0.10

10

20

30

40

50

60

70

P = -0.30 ± 0.03 mbar

En

trie

s

Overpressure (mbar)

C. Garabatos, GSIC. Garabatos, GSI

Concerns about cryogenics method

For on-line regeneration: Long regeneration times: several weeks Safety: lack of NL2 would result in loss of gas and

perhaps loss of the plant Need extra Xe volumes Composition gets modified Consider, for the filling, the use of membranes

(Fill with CO2, not with N2) During running periods, leaks must be kept to a

minimum Use cryogenics only at end-of-run is desirable


Semi permeable membrane test(from ATLAS TRT)

CO2-enriched

Gas in

Permeate out(CO2)

Polyamide capillary tubes


Performance expectationsfor one TRD filling

Pressure

(bar)

Xe lost (m3)

Time (days)

Xe lost(m3)

Time (days)

1 2 6.5 1.3 6.5

2 2 4.5 1.0 4.5

3 2 3.5 0.9 3.5

4 2 2.8 0.8 2.8

1 membrane 2 membranesC. Garabatos, GSIC. Garabatos, GSI

Summary

N2 removal feasible at end-of-run

Also possible on-line, but long and tedious

membranes look attractive for the filling (with CO2)

last crucial test (gas distribution) are being carried out right now

PRR after PRR of ATLAS TRT No document à la TPC foreseen


The leak question

0

10

20

30

40

50

0 0.2 0.4 0.6 0.8 1Absolute leak rate (l/h)

ppm

or k

€/ye

ar [O2] (ppm)

money (k€/year)

Leak rate 0.27 l/hReg. Flow = leak rate

0

1

2

3

4

5

0 50 100 150 200 250

time (days)[N

2 ] (%

)


Electronics Progress

PASATRAP – ADC, digital filter, tracklet

pre-processor, tracklet processor, controls

read out boardDCSgrounding services

PASA - Chip

Parameter

No. channels 18+3

Noise (ENC) 702 e (25pF)20e/pF

Conversion Gain

12.5 mV/fC

Shaping time about 120 ns

Non-linearity < 0.16%

Power consumption

13.5 mW/ch

output variationswith T, Vdda

<0.23% (20 deg)<0.03% (200mV)

-> fully differential design

-> essentially ready for submission (end of April)

-> final simulations in conjunction with ADC ongoing

-> potential problem with ground loop under investigation

H.K. Soltveit, V. Catanescu

Measured Crosstalk as Function of Pad-Pad Capacitance

max. input signal

crosstalk in %

H.K. Soltveit, V. Catanescu, I. Rusanov

ADC

10bit, 10MHz cyclic converter designed by University of Kaiserslautern

current design needs 0.1mm2 and 6mW needs additional input buffer for decoupling from

PASA no longer providing reference voltages to PASA potential ground loop because input cells also

need analog 3.3V full design with 21 channels will be part of the

next submission (May)

D. Muthers, R. Tielert, KL

ADC Chip Performance

490

500

510

520

530

540

Input amplitude 100 mV, 576 samples

AD

C o

utpu

t

0 100 200 300 400 500

-2

0

2

RMS=0.869 for timebins>99

RE

S

Timebin

- ADC tested with all CPUs running and IRQs turned on- ADC power derived from digital power and turned on from idle state (unrealistic worst case)- observed drift less than 1 bit- rms deviation from fit to pure sine wave < 0.9 bit

V. Angelov, HD

Tracklet Preprocessor

DFIL

Event Buffer

Condition Check

DFIL Event Buffer

DFIL

Event Buffer

Condition Check

DFIL

Event Buffer

Condition Check

DFIL Event Buffer

DFIL

Event Buffer

Condition Check

Qhit

hit

Qhit

Qhit

18+1 channels

COGPosition

CalcLUT

Para-meterCalc

Hit

Sel

ectU

nit (

max

. 4 h

its)

PositionCalcLUT

Para-meterCalc

PositionCalcLUT

Para-meterCalc

PositionCalcLUT

Para-meterCalc F

IT R

egis

ter

Fil

e an

d tr

ackl

et s

elec

tion

CPU0

CPU1

CPU2

CPU3

C

RL

A

AACOG

Q

COG

COG

COG

ADC

ADC

ADC

ADC

ADC

ADC

Non-Lin

Offs Tail-canc

Gain Cross-talk

Digital FILter64 timebins deep

FIT register file is for the CPUs a readonly register file

V. Angelov, HD

Pedestal correction (offset)

This filter stage corrects for some offset in PASA and ADC and adds a programmable offset to the corrected value

V. Angelov, HD

Tail cancellation filter

This filter stage corrects for the gas ion tail. It is a IIR filter. The tail can be approximated

by a sum of two exponentials.

The parameters are selected with the requirements: output pulse has nearly Gaussian shape and no undershoot.

V. Angelov, HD

Summary of Test Results

What has been tested :Serial Configuration, most of the configuration registers in all blocks, connected to the Global Bus;Clock gating, Global State Machine;The large LUTs (non-linearity, position), Event Buffers;CPUs with Register Files and Interrupt controllers;DFF Instruction and Quad Port Data Memories, Quad Port Full Custom Instruction and Data Memories;Local Buses;parallel Network outputs with the delay units;Acquisition in the event buffers, digital filters;ADCs;PLL, Clock and Pretrigger distribution outputsparallel Network inputs

What is still not tested : Real acquisition mode

V. Angelov, HD

Summary of Test Results

many functional bugs - none of them makes the chip unusable. For final version they are not acceptable

-> simulate !CPUs operate at clocks up to 70-80 MHz,

instead of 120MHz. Some parts operate reliably up to 120MHz (SCSN, GSM). -> timing analysis !

The ADC parameters (noise and some bad effects at large amplitudes) are not influenced by switching the CPUs on

V. Angelov, HD

Read Out Boards

-> one board for all layers

I. Rusanov, HD

MCM BoardsI. Rusanov, HD

-> designed as BGA

-> direct chip-to-chip bonding

-> version with PASA, ALTRO, and TRAP chip still needs to be evaluated

Noise Measurements on Large PrototypeI. Rusanov, M. Ciobanu, T. Mahmoud

-> frequency response of PASA on the bench


-> typical response without good shielding/grounding


-> response with current shielding/grounding concept

TRD DCS Card

one card per chamber DIMM connector contains TTC FPGA running Linux Ethernet network multiplexed ADC inputs for monitoring T,V etc. needs about 5W

DCS board ---> KIP software ---> Worms

M. Stockmeier, V.Petracek, D. Gottschalk

ALICE-TRD Workshop, 3.3. – 4.3.03, TrentoALICE-TRD Workshop, 3.3. – 4.3.03, Trento Bernd Windelband, Uni HeidelbergBernd Windelband, Uni Heidelberg

SupermoduleSupermodule

Length: 7mLength: 7mWeight: ~ 300kgWeight: ~ 300kgFully equipped: ~ 1,2 toFully equipped: ~ 1,2 to


New chamber segmentationNew chamber segmentation

• 12 different chamber types12 different chamber types• Largest ROC 1,45m x 1,2mLargest ROC 1,45m x 1,2m• Only 2 differnt types per Only 2 differnt types per

layerlayer


SupermoduleSupermodule

TOFTOF

TRD SMTRD SM

Rail-roller systemRail-roller system


SupermoduleSupermodule„2/5“ Prototype„2/5“ Prototype


SupermoduleSupermoduleservice spaceservice space

-> space for services very tight

-> 4mm reduction of chamber width on both sides


SupermoduleSupermoduleRail SystemRail System

Fixed railFixed rail movable railmovable rail

To avoid additional load from the space frameTo avoid additional load from the space frame


Supermodule into LDSSupermodule into LDS

•Handling and transport frameHandling and transport frame

•Lifting deviceLifting device

•supermodulesupermodule


Lifting deviceLifting device(LDS)(LDS)

Readout Chambers

dimensions frozen new pad plane backing currently evaluating with

two large chambersassembly proceduretoolingtest procedureleak tightnessgain uniformitytolerances

PRR April,30 ready for production in

Heidelberg starting in May

Drift volume

Radiator

Padplane/Read out unit

Side frame

H. Appelshaeuser, D. Emschermann, T. Mahmoud

Assembly of TRD Chambers

- clean room- 3D measurement system- precision mounting jigs

Chamber + Radiator

Radiator Production in Münster

all fiber material ordered material cut for largest

modules backing on order from

AIK and Fischer 3 glass tables ready

can work on 2 radiators/table

tools in preparationdone for first radiators

assembly of 6 radiators in parallel

neglecting man power2 radiators ready / day

D. Bucher, W. Verhoeven

Deformations of Wire Grids after Wiring

-> well within acceptable tolerances

H. Appelshaeuser

Wire Spacing After Wiring

-> without (!) combs for wire alignment

H. Appelshaeuser

Wire Tension Measurements

cathode anode

-> deformation due to cathode as expected; no effect on anode

D. Emschermann

Pad Planes

designs for all chambers almost finished

alternating tilted pads designwill have identical footprint on

readout sideforesee NO connector on pad plane,

instead use Z-bonding tape for direct connection of cable to read out board

D. Emschermann

Software Developments

framework well advancedneeds implementation/parameterization of

actual TR response for PID simulationneeds implementation of services trigger simulation ongoing along with

hardware implementation scheme

NEED backward compatibility of AliROOT

General Planning

would like to initiate integration meeting with TOF and technical coordination

will aim for re-baselining of the detector after PRR of chambers and submission of digital chip (catch up during production)

report from trd workshop trento, march 3-4 results from test beam analyses tr–production and...

Documents

andronic slide

busch slide

lehmann slide

garabatos slide

dc5 slide

muenster slide

magnetic field slide

tr measurements beam