1 A CLUster COUnting Drift Chamber for ILC F.Grancagnolo, INFN – Lecce.
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Transcript of 1 A CLUster COUnting Drift Chamber for ILC F.Grancagnolo, INFN – Lecce.
1
A CLUster COUnting Drift Chamber for
ILC
F.Grancagnolo, INFN – Lecce
2
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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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4thConcept TPC(160 pads)
4thConcept TPC+ 5 pixel planes
this CLUCOU
Drift Chamber
Momentum Resolution
sin105
1024
5
p
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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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.
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
15F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
17F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
CLUCOU Proposal presented @ during
18F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
rendering offirst two
superlayer stereo
19F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
20F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
21F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
22F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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
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6.4 m
7.7 m
12.8 m x 15.4 mdiameter x length
4thConcept layout
24F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
- BARREL
CLUCOUchamber
MUD barrel
MUD
E C N A D P
4thConcept Dual Solenoid
25F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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
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Drift tube end plug detail
27F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
×18
×36
×18650
tubes26 cards
550 tubes
22 cards
1750 tubes
70 cards
Modularity
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×3
10500 tubes
420 cards
1/3 of barrel
29F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
1440 tubes 1632 channels
76 cards
×6
1/3 end cap
30F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
×2
One end cap
31F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
Barrel:31500 tubes21000 channels 840 cards
End caps: 8640 tubes 9792 channels 456 cards
Total:40140 tubes30792 channels 1296 cards
Full muon system
32F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
+ − at 3.5 GeV/c
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Downscaling to SuperB
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
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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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---
35
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 ---
36
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
F. Grancagnolo. INFN – Lecce --- CLUCOU for ILC ---