A Silicon Vertex Tracker
for
Atsushi Taketani
1. Physics goal
2. Structure of detector
3. Status and plan
4. Expected performance
5. Summary
PHENIX Vertex Group (86 Participants from 15 institutions)
M. Baker, R. Nouicer, R. Pak, A. Sukhanov, P. Steinberg, Z Chai
Brookhaven National Laboratory, Chemistry Department
Z. Li
Brookhaven National Laboratory, Instrumentation Division
J.S. Haggerty, J.T. Mitchell, C.L. Woody, E. O’Brien, D. Lynch
Brookhaven National Laboratory, Physics Department
A.D. Frawley
Florida State University
J. Crandall, J.C. Hill, J.G. Lajoie, C.A. Ogilvie, A. Lebedev, H. Pei, J. Rak, G.Skank,
S. Skutnik, G. Sleege, G.Tuttle
Iowa State University, Ames,
M. Tanaka
KEK
N. Saito, M. Togawa, M. Wagner
Kyoto University
H.W. van Hecke, G.J. Kunde, D.M. Lee, M. J. Leitch, P.L. McGaughey, W.E. Sondheim
Los Alamos National Laboratory
T. Kawasaki, K. Fujiwara
Niigata University
T.C. Awes, M. Bobrek, C.L. Britton, W.L. Bryan, K.N. Castleberry, V. Cianciolo, Y.V. Efremenko,
K.F. Read, D.O. Silvermyr, P.W. Stankus, A.L. Wintenberg, G.R. Young
Oak Ridge National Laboratory
Y. Akiba, J. Asai, H. En’yo, Y. Goto, J.M. Heuser, H. Kano, H. Ohnishi, V. Rykov,
T. Tabaru, A. Taketani, K.Tanida, J. Tojo, Y. Onuki
RIKEN
S. Abeytunge, R. Averbeck, K. Boyle, A. Deshpande , A. Dion, A. Drees, T.K. Hemmick,
B.V. Jacak, C. Pancake, V.S. Pantuev, D. Walker
Stony Brook University
B. Bassalleck, D.E. Fields, M. Malik, C. Hagemann
University of New Mexico
O. Drapier, F. Fleuret, M.Gonin, R. G. de Cassagnac, A. Romana E. Tujuba
Eole Polytechnique
K. Kruita, Y. Inoue
Rikkyo Univesity
Physics Goals
Open up new horizon!
Heavy Ion program
Spin program
• Potential enhancement of
charm production.
• Open beauty production.
• Flavor dependence of jet
quenching and QCD energy
loss.
• Beauty and charm separation
• Accurate charm reference for
quarkonium.
• Thermal dilepton radiation.
• Upsilon spectroscopy, e+edecay channel
• g -Jet correlation
• Investigating nucleon spin
structure by polarized protonproton collider to utilize
quark/gluon as probe, instead
of DIS lepton.
• gluon polarization by using
beauty / charm final state.
• gluon polarization by using g +
jet final state.
• Flavor decomposition by using
W->e channel.
Physics Goal
Spin Program
V2
b contribution ?
Gluon Polarization
Heavy Ion Program
Pt [GeV]
Charm and bottom identification by displaced vertex
Jet identification with larger acceptance
NSAC recommendation
October 7, 2004
Within a constant level of effort budget, the
Subcommittee recommends that certain essential
investments be made. These include:
 Construction of the PHENIX Silicon Vertex Tracker
and the STAR Time-of-Flight Barrel;
 Participation in the LHC Heavy-Ion program;
 Investment in RHIC accelerator and detector R&D;
 Construction of the EBIS;
 Support at the present level for university and national
laboratory research;
 Provision for RHIC running time sufficient to preserve
the integrity of the Heavy-Ion and Spin Physics
programs.
Current PHENIX
Pioneering High Energy Nuclear Interaction eXperiment
PHENIX Detector
Si Vertex Tracker
1 Central Arm
e, g, Charged Hadrons detection
|h|<0.35, Df=p
2, Muon Arm
m detection
1.2<|h|<2.4, 2p in f
3, Forward detectors
Luminosity Monitoring
Centrality
Local polarimetery
Good particle identification (But no direct b/c identification)
High Rate and High Detector granularity.
Limited geometrical coverage (Not 2p in central region)
Requirements for Vertex Tracker
Physics side
• High precision tracking for displaced vertex measurement.
40mm displaced vertex resolution, ct ~ 100mm(D), ~400mm(B)
• Large coverage tracking capability with momentum resolution
(|h|<1.2 , and full azimuthally with s/P ~ 5%P)
Environment side
•
•
•
•
High charged particle density ‘dN/dh’ ~ 700 @h=0
High Radiation Dose ~100KRad@10Years
High Luminosity 2 1032 cm 2 s 1 @PP -> High rate readout
Low Material Budget <- avoid multiple scattering and photon
conversion for electron measurement by outer detectors.
Structure
 Barrel region
•
|h|<1.2, almost 2p in f
•
Pixel sensor at inner 2 layers
•
Strip sensors at outer 2 layers
 Forward region
•
1.2<|h|<2.7, 2p in f
•
4 layers of mini strip
(50 x 2000 to 11000 mm)
•
Trigger capable
Strip
R=10 and 14cm
Pixel
Poster by K.Fujiwara(#292)
D.E.Field (#290)
R=2.5 and 5cm
Poster by G.J.Kunde(#297)
PIXEL (Sensor and Readout)
Pixel size( x z） 50 µm x 425 µm
Sensor Thickness 200um
r = 1.36cm, z = 1.28 cm
256 x 32 = 8192 channel / sensor
4 sensor / chip
4 chip / ladder
Readout by ALICE_LHCB1 chip
• Amp + Discriminator / channel
•Bump bonded( 2 dim. Soldering) to each pixel
•Running 10MHz clock ( RHIC 106nsec )
•Digital buffer for each channel > 4usec depth
•Trigger capability > FAST OR logic for each crossing
Used at NA60 (Rad hard)
PIXEL readout
Al-Kapton Bus readout to
minimize material
(120micron pitch )
15μm
PIXEL readout
Pilot
module
4x parallel readout
32
256
128bit width bus
Ver.1 is running.
Ver.2 will come in Summer
PHENIX Digital Pilot
•ALICE chip is 32bit input/40MHz x 16bit output
•New chip is 64bit input/40MHz x 32bit output
Strip layer
Two strip-pixel arrays on a single-sided wafer of 500 µm
thickness, with 384 + 384 channels on 3 x 3 cm2 area.
Sensor elements:
Initial design:
“longitudinal”
readout.
Made by
SINTEF
Pixels: 80 µm  1 mm, projective readout via
double metal XU/V “strips” of ~3 cm length.
Developed at BNL Instrumentation Gr.
Single sided
new design:
“lateral” SVX4
readout.
Made by
Hamamatsu
1+1 dimensional readout 3cmx3cm sensor x2 / chip
( X and U direction)
768 X strip and 768 U strips/chip
Position resolution is 25mm by test beam
Strip Readout
“RC Chip”
“RC Chip”
“RC Chip”
“RC Chip”
“RC Chip”
“RC Chip”
SVX4
U1
SVX4
X1
SVX4
X2
SVX4
X6
SVX4
U6
SVX4
U5
Control signal daisy-chain
RCC
Power daisy-chain
Data signal daisy-chain
SVX4
U2
SVX4
U3
SVX4
X3
SVX4
X5
SVX4
X4
SVX4
U4
“RC Chip”
“RC Chip”
“RC Chip”
“RC Chip”
“RC Chip”
“RC Chip”
SVX4 Readout chip
Developed by FNAL for
TEVATRON RUN2b (Rad hard)
8 bit ADC for each channel
128 channel per chip
Readout3cm
Testx6cm
boardsensor
(Testing now)
3 SVX Chip
Packing factor is same
Control by onboard FPGA
Schedule and status
•
•
•
•
•
•
•
Pixel Readout test
End of 2005
Strip Readout test
Fall of 2005.
Structure design study
Start now
Prototype ladder
Early 2006
Production (Japan)
Start in 2005
Production (US)
2007
Installation complete
2009
(Possible early partial implementation)
• Total cost ~8M US$ (Japan, US, France)
Expected Performance
D0 decay
Collision Vertex
Layer
radius
Sensor
Occupancy
Layer 1
2.5 cm
Pixel
0.53 %
Layer 2
5.0 cm
Pixel
0.16%
Layer 3
10.0 cm
Strip
Layer 4
14.0 cm
Strip
4.5 %
4.7 %
(x-strip)
(u-strip)
2.5 %
2.7 %
(x-strip)
(u-strip)
Expected occupancy at Au-Au
200GeV most central event
Distance to the Closest Approach [cm]
Spin performance
parton X reconstruction by g + Jet
Using only Photon information
Photon + 2p VTX tracker
Great improvement with VTX
Summary
• PHENIX Silicon Vertex Tracker will open new
physics horizon for both Heavy Ion and Spin
program of RHIC.
• There are two of inner pixel layers, two of outer
strip layers and forward mini-strips
• Hardware R&D work is on going.
• Completer installation in 2009 for RHIC
RUN9(2009/2010).
• Plans underway for early partial implementation.
Related Posters
Forward Silicon G.J. Kunde (#297)
Pixel Layer
K. Fujiwara(#292)
Strip Layer
D.E. Field (#290)
Structure summary (Backup)
VTX
Layer
R1
R2
R3
R4
Geometrical
dimensions
R (cm)
2.5
5
10
14
z (cm)
21.8
21.8
31.8
38.2
Area (cm2)
280
560
1240
1600
Sensor size
R  z (cm2)
1.28  1.36
(256 × 32 pixels)
3.43 × 6.36
(384 × 2 strips)
Channel size
50  425 mm2
80 mm  3 cm
(effective 80  1000 mm2)
Sensors/ladder
28
Channel count
Radiation length
(X/X0)
5
6
Ladders
10
20
18
26
Sensors
160
320
90
144
Readout chips
160
320
1080
1728
Readout channels
1,310,720
2,621,440
138,240
221,184
Sensor
0.2%
0.5 %
Readout
0.16%
0.8 %
Bus
0.14%
Ladder & cooling
0.7%
0.7 %
Total
1.2%
2.0 %