1 a cluster counting drift chamber for ilc f.grancagnolo, infn – lecce

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A CLUster COUnting Drift Chamber for

ILC

F.Grancagnolo, INFN – Lecce

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outline

•Requirements for tracking at ILC

•Cluster Counting

•4thConcept CLUCOU Drift Chamber

•4thConcept MUon Detector

F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---

3F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---

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From Gluckstern:

2

0

2

2

2

sin/ 016.0

4320

XL

pLcGeV

NL

0

3

2

102.74

3.5XL

pNp

p

@ ILC, for B = 5 T, L = 1.5 m

2

0

6 102 1044

X

LN N = 150 , L ~ 2m

(1 cm2 hex. cells) 60.000 sense wires120.000 field wires

! 100 ! 50 0 mXm

Bp

3.0 1


sin101

1023

5

p

5

sin105.0 3

2

pp

p

Multiple scattering contribution (equivalent

L/X0): 60.000 20 m W sense wires → 1.8 × 10-3 (X0 = 0.35 cm)120.000 80 m Al field wires → 2.2 × 10-3 (X0 = 8.9 cm) 2 m gas (90% He + 10% iC4H10) → 1.5 × 10-3 (X0 = 1300 m)

Equivalent L/X0 = 5.5 × 10-3

Sagitta measurement contribution (in plane):

mxy 50

mX 3600


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4thConcept TPC(160 pads)

4thConcept TPC+ 5 pixel planes

this CLUCOU

Drift Chamber

Momentum Resolution

sin105

1024

5

p


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CLUster COUnting2 cm drift tube

90%He-10%iC4H10

few x 10 gain5

t : time separation between consecutive ionization clusters,as a function of their ordered arrival time, for different impact parameters. (caveat: electrons!)

i+1,i

In this He mixture , provided that: sampling frequency of signals > 2 Gsa/s and rise (and fall) time of single electron signals < 1ns single electron counting is possible.


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CLUster COUntingMC generated events:2cm diam. drift tubegain = few x 10gas: 90%He–10%iC4H10

no electronics simulatedvertical arbitrary units

cosmic rays triggeredby scintillator telescopeand readout by:8 bit, 4 GHz, 2.5 Gsa/sdigital sampling scopethrough a 1.8 GHz, x10preamplifier

b=0 b=1 cm

10 mV 500 ns

trigger signal

t0 tlasttfirst

tmax=1.6 s


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CLUster COUntingCLUster COUntingFor a given set up, and a digitized pulse (tlast is constant with a spread < 20 ns)

t0 = tlast – tmax gives the trigger time

bf = ∫ v(t) dt first approx. of impact parameter b

(c/2)2 = r2 - bf2 length of chord

Ncl = c / (() × sin) expected number of cluster

Nele = 1.6 x Ncl expected number of electrons(to be compared with counted one)

{ti } and {Ai }, i=1,Nele ordered sequence of ele.drift times and their amplitudes

P(i,j), i=1,Nele, j=1,Ncl probability i-th ele. to j-th cl.

Di (x) = (1-x) x

probability density function of ionization along track

tfirst

t0

Ncl!

(Ncl-i)! (i-1)!Ncl-i i-1Ncl


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Each cluster contributes to the measurement of the impact parameter with an

independent estimate weighted according to the Poisson nature of the process

and the electron diffusion along the drift path.The resolution on the impact parameter, b, improves with the addition of

each cluster beyond the first one.It, however, saturates at a value of 30-35 m, convolution of: spread in mechanical tolerances (position of sense wire; gravitational

sag; electrostatic displacement)

timing uncertainties (trigger timing; electronics calibration; t0) degree of knowledge of time-to-distance relation instability of working parameters (HV, gas temperature and pressure,

gas mixture composition)

Fit to resolution function:

(from KLOE data)

= 77014 mnp = 12.9 cm-1

D = 140 m cm-1/2t = 4.8 0.2 ns

b

b

Reasonable to assume b = 50 m per sense

wire


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Particle Identificationgas mixture = 95%He+5%iC4H10 Ncl = 10/cm

beam test m

easurements

p = 200 MeV/c

experiment:

theory: trunc. mean:

CLUCOU chamber expected dNcl/dx resolution for a 2 m m.i.p. at 13 cluster/cm:

(dNcl/dx)/(dNcl/dx) = 2.0 %F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---

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4thConcept ILC Drift Chamber Layout and assembly technique

Length:3.4 m at r = 22.5 cm3.0 m at r = 147.0 cm

Spherical end plates:C-f. 12 mm + 30 m Cu(0.047 X0)

Inner cylindrical wall:C-f. 0.2 mm + 30 m Al(0.001 X0)

Outer cylindrical wall:C-f./hex.cell. sandwichheld by 6 unidir. struts 0.020 X0)

Retaining ring

Stiffening ring

Gas = 0.0015 X0

Wires = 0.0040 X0

TOTAL = 0.028 X0


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4thConcept ILC Drift ChamberLayout

Hexagonal cells f.w./s.w.=2:1

cell height: 1.00 1.20 cmcell width: 6.00 7.00 mm

(max. drift time < 300 ns !)

20 superlayers, in 200 rings10 cells each (7.5 in average)at alternating stereo angles ±72 ±180 mrad(constant stereo drop = 2 cm)

60000 sense w. 20 m W120000 field w. 80 m Al

“easy” t-to-d r(t) (few param.)

>90% sampled volumeF. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---

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Summary for ILCA drift chamber à la KLOE with cluster counting (≥ 1GHz, ≥ 2Gsa/s, 8bit)

• uniform sampling throughout >90% of the active volume• 60000 hexagonal drift cells in 20 stereo superlayers (72 to 180 mrad)• cell width 0.6 ÷ 0.7 cm (max drift time < 300 ns)• 60000 sense wires (20 m W), 120000 field wires (80 m Al)• high efficiency for kinks and vees• spatial resolution on impact parameter b = 50 m (z = 300 m) • particle identification (dNcl/dx)/(dNcl/dx) = 2.0%

• transverse momentum resolution p/p = 2·10-5 p 5·10-4

• gas contribution to m.s. 0.15% X0, wires contribution 0.40% X0

• high transparency (barrel 2.8% X0, end plates 5.4%/cos X0+electronics)• easy to construct and very low cost

is realistic, provided:

• cluster counting techique is at reach (front end VLSI chip)• fast and efficient counting of single electrons to form clusters is possible• 50 m spatial resolution has been demonstrated



Drift Chamber for CMD-3 Detector @ VEPP-2000, Novosibirsk

G.V. Fedotovich and the CMD-3 Collaboration

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to be presented at



CLUCOU Proposal presented @ during


rendering offirst two

superlayer stereo


highest multiplicity

events:

≥ 300 tracksper such

event

jetsttee 6

fraction of hit cellsper ring

superlayer

average number of tracks

crossing a hit cell

300 cells

680 cells


6.4 m

7.7 m

12.8 m x 15.4 mdiameter x length

4thConcept layout


- BARREL

CLUCOUchamber

MUD barrel

MUD

E C N A D P

4thConcept Dual Solenoid


radius 2.3 cm filled with 90% He – 10% iC4H10 @ NTP gas gain few × 105

total drift time 2 µs primary ionization 13 cluster/cm ≈ 20 electrons/cm total both ends instrumented with:

• > 1.5 GHz bandwith• 8 bit fADC• > 2 Gsa/s sampling rate• free running memory

for a • fully efficient timing of primary ionization: cluster

counting• accurate measurement of longitudinal position with

charge division • particle identification with dNcl/dx

-system basic element: drift tube


Drift tube end plug detail


×18

×36

×18650

tubes26 cards

550 tubes

22 cards

1750 tubes

70 cards

Modularity


×3

10500 tubes

420 cards

1/3 of barrel


1440 tubes 1632 channels

76 cards

×6

1/3 end cap


×2

One end cap


Barrel:31500 tubes21000 channels 840 cards

End caps: 8640 tubes 9792 channels 456 cards

Total:40140 tubes30792 channels 1296 cards

Full muon system


+ − at 3.5 GeV/c

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Downscaling to SuperB


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SuperB Drift Chamber Layout and assembly technique

Length × Diameter :~ 2.8 m × 0.8 m Spherical end plates:C-f. 6 mm equivalent+ 30 m Cu (0.024 X0)

Inner cylindrical wall:C-f. 0.2 mm + 30 m Al(0.001 X0)

Outer cylindrical wall:C-f./hex.cell. sandwichheld by 6 unidir. struts 0.020 X0)

Retaining ring

Stiffening ring

Gas = 0.0014 X0

(80%He+20%iC4H10) Wires = 0.0004 X0

TOTAL = 0.023 X0


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SuperB Drift ChamberLayout

Hexagonal cells f.w./s.w.=2:1

cell height: ~ 1.70 cmcell width: ~ 10. mm

(max. drift time < 700 ns !)

10 superlayers in 100 rings10 cells each (7.5 in average)at alternating stereo angles ±72 ±130 mrad(constant stereo drop = 2 cm)

12000 sense w. 20 m W 24000 field w. 80 m Al

“easy” t-to-d r(t) (few param.)

>90% sampled volumeF. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---

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Summary for SuperBA drift chamber à la KLOE with cluster counting (≥ 1GHz, ≥ 2Gsa/s, 8bit)

• uniform sampling throughout >90% of the active volume• 12000 hexagonal drift cells in 8 stereo superlayers (72 to 130 mrad)• cell width ~ 1.0 cm (max drift time < 700 ns)• 12000 sense wires (20 m W), 24000 field wires (80 m Al)• high efficiency for kinks and vees• spatial resolution on impact parameter b = 50 m (z = 400 m) • particle identification (dNcl/dx)/(dNcl/dx) = 2.3%

• transverse momentum resolution p/p = 1.0·10-3 p 1.5·10-3

• gas contribution to m.s. 0.14% X0, wires contribution 0.03% X0

• high transparency (barrel 2.2% X0, end plates 2.6%/cos X0+electronics)• easy to construct and very low cost

is realistic, provided:

• cluster counting techique is at reach (front end VLSI chip)• fast and efficient counting of single electrons to form clusters is possible• 50 m spatial resolution has been demonstrated


1 a cluster counting drift chamber for ilc f.grancagnolo, infn – lecce

Documents

ilc cluster

infn lecce slide

clucou chamber

track t

max drift time

ns b b reasonable

number of cluster n

drift times