Transcript PHENIX High pt Upgrades -- Overview --

PHENIX High pt Upgrades
-- Overview --
Yasuo MIAKE for High pt Upgrade Team
http://utkhii.px.tsukuba.ac.jp/~highpt/
Proposal
• To enhance the PID capability of PHENIX,
we like to install Aerogel counters (160 cells)
at W1 Sector on the West Arm.
• Together with the Aerogel, TOF and RICH,
we can extend the PID beyond 5 GeV/c.
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Yasuo MIAKE, Univ. of Tsukuba
Proposed Extention of PID with Aerogel
Pion-Kaon
separation
TOF
s~100 ps
0 - 2.5
0
RICH
Aerogel
Kaon-Proton
separation
n=1.00044
gth~34
0
n=1.011
gth~6.8
0
4
-5
8
0
4
8
0
4
8
0
4
5 - 17
4
1-5
4
8
17 5-9
8
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Note ; Aerogel together with TOF can extend the PID capability upto 10 GeV/c
(Without TOF, no K-proton separation at < 5 GeV/c)
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Yasuo MIAKE, Univ. of Tsukuba
Physics Motivations
• From basic strategy, it is
natural extension for
PHENIX to extend its PID
in higher pt region.
• Strong motivation given;
– Jet Quenching!?
– Large suppression of pions
at high pt , while protons
show binary scaling!?
• Meson/baryon puzzle?
• Need to extend PID > 5
GeV/c
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Yasuo MIAKE, Univ. of Tsukuba
Transition Region to Jet Fragmentation
• Hadronic Flow vs
Flow at Quark
Level?
• Seems to important
to measure the
transition region to
Jet fragmentation.
• PID (pion, kaon,
proton) beyond 5
GeV/c is the goal.
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Yasuo MIAKE, Univ. of Tsukuba
What STAR is doing
• We like to go beyond 6 GeV/c with pion, kaon and proton.
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Yasuo MIAKE, Univ. of Tsukuba
Aerogel Panel on the West
Integration
Volume
PMT
Rφ
PMT
Aerogel
(11x22x11 cm^3)
160 Cells
Ｚ
• 4.5 m from the vertex to the center of
Aerogel.
• Coverage ; full z, 15 degree in phi.
• Space available for new TOF.
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Yasuo MIAKE, Univ. of Tsukuba
Design of Aerogel Panel
rφ
Side View
118 cm
(10 cells)
400 cm (16 Cells)
Z
Top View
r
30 cm
• Direction of every other cell is reversed,
so that
– Aerogel locates at the same distance from
the vertex,
– No dead space in between.
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Yasuo MIAKE, Univ. of Tsukuba
Cell Design
Prototype in run3-pp
air
11cm
Aerogel
n=1.0112
+- 0.0002
22cm
11cm
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Yasuo MIAKE, Univ. of Tsukuba
PMT assembly (prototype)
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Yasuo MIAKE, Univ. of Tsukuba
Silica Aerogel
• Best index with RICH(CO2) is
n< 1.007, too small.
• SP-12M (Matsushita)
– Silica aerogel with Lowest
refractive index commercially
available.
– Hydrophobic
• Long term stability proved by
KEK-Belle.
Refractive Index (Measured)
Density [g/cm^3]
1.0114 +- 0.0008
0.04
Transmission for 10 mm (Measured)
Tile Size [mm]
64 % @ 400 nm
88% @ 550 nm
112.5 x 112.5 x 11.0
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Yasuo MIAKE, Univ. of Tsukuba
PMT
• 3” PMT for photon counting
• Gain of > 10^6 at 1500 V w. 11-1-1- voltage divider
• One p.e. resolution
1 p.e.
2 p.e.
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Yasuo MIAKE, Univ. of Tsukuba
Bleeder
• Hand made bleeder
–
–
–
–
Thinner material
Less space
Less power (330 mW@1500V) than Hamamatsu standard
Tested upto 3.2 kV for 6 hours
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Yasuo MIAKE, Univ. of Tsukuba
Magnetic Field on the West
• Magnetic field of the location
measured as < 8 G.
– Goal set as 16 Gauss !
• Thickness & Size of the mu-metal
shield has been optimized using
Helmholz Coil.
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Yasuo MIAKE, Univ. of Tsukuba
Mu-metal Shield
• Magnetic shield of 0.2
mm thick breaks down
at around 10 G.
– Loss of Gain &
– Loss of Q.E.
• Magnetic shield of 0.5
mm survive till 20 G.
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Yasuo MIAKE, Univ. of Tsukuba
Final Prototype Test at KEK
• June, 2003 at KEK
–
–
–
–
SP-12M
R6233-01HA w. Bleeder
Pre-Amp w. cables
Dubna Box
• Expected performance
– Normal ~ 14 p.e.
– Reverse ~ 12 p.e.
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Yasuo MIAKE, Univ. of Tsukuba
Observed Clean Signal
Final Prototype w. SP-12M
+2 GeV/c
~6.6 p.e./PMT
1 p.e. peak
~0.4 p.e./PMT
• Very clean separation
– Amount of photons other than Aerogel Chrenkov is small!
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Yasuo MIAKE, Univ. of Tsukuba
Observed Uniform Response
Reverse
Normal
Oops!
• Uniform response, thanks to Integration Volume
– Important to separate in the momentum region of slow rise
• ~10% diff. between normal/reverse, due to diffusive nature of aerogel
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Yasuo MIAKE, Univ. of Tsukuba
Uniformity Confirmed at Dubna
• Independent Beam Test at
Dubna in June 2003.
• Tested at Dubna with final
prototype, but with SP-15.
• Independent setup &
calibrations
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Yasuo MIAKE, Univ. of Tsukuba
Cherenkov Light from PMT window
Aerogel
(n=1.011)
PMT glass
(n=1.5)
Time
Time
P. H.
P. H.
• Cherenkov from PMT window;
– Huge pulse height
– Faster Timing (> 5 20
ns)
Yasuo MIAKE, Univ. of Tsukuba
Background Rejection
• Photons from PMT windows can be
identified/recognized by itself,
– Faster Timing (>5 ns)
• Consistent with optical
simulation
– ADC-ADC correlation
• Other sources of photons are
carefully surveyed and <1p.e.
• TDC-TDC difference can be used
for track association.
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Yasuo MIAKE, Univ. of Tsukuba
Simulation for PID Performance
• Assumptions;
– HIJING Au+Au 200 GeV
– Aerogel;
• n =1.011
• Saturated at 14 p.e. w.
poissson distr.
• Occupancy 10%
– RICH ;
• n =1.0044 (CO2)
• Saturated at 10 p.e. w.
poissson distr.
• Occupancy 3.4 % (NIM)
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Yasuo MIAKE, Univ. of Tsukuba
Expected Proton Identification
• Require No-Aerogel & No-RICH
Occupancy
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Yasuo MIAKE, Univ. of Tsukuba
Expected Kaon Identification
• Require Aerogel & No-RICH (Need TOF for < 5 GeV/c)
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Yasuo MIAKE, Univ. of Tsukuba
PISA Activity
• All the known material put
into PISA.
• Occupancy ~ 8 %
#of fired cell/
central event
back ground sources
seen in aerogel detector
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~ 8% occupancy
Yasuo MIAKE, Univ. of Tsukuba
Radiation Length by PISA
• <Lrad> ~20 %
– Similar to TOF
Radiation Length [%] -->
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Yasuo MIAKE, Univ. of Tsukuba
Aerogel/PMT Preparation at Tsukuba
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Yasuo MIAKE, Univ. of Tsukuba
Box Production/Inspection at Dubna
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Yasuo MIAKE, Univ. of Tsukuba
Dubna Contributions
• Dubna contributions have been very
important from R&D’s to productions.
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Yasuo MIAKE, Univ. of Tsukuba
Status of Safety Issues
• Known issues; PMT-holder, HV protector
Item
Fire
Susumu Sato/ Motoi Inaba
Electrica
l
Status
1) Aerogel
2) Nyron(MC901)
3) Aluminum
4) Mylar
5) Gore-tex
6) PMT-Bleeder (G10)
Estimated ?
?
-
3.2 kV
New
New
Tested
7) Signal connector PreAMP
8) Signal connector Box
9) H. V. Connector
10) LED connector
UL94V-0
UL91V-0/ UL94-0
UL94V-0
UL94V-0
300 V
3 kV
3 kV
600 V
New
Used at EMCal
Used at EMCal (but 3-pin)
(Small type of )
11) Signal cable to PreAMP
12) Signal Cable from
PreAMP
13) High voltage cable
14) LED cable
15) L. V. cable for PreAMP
UL ?
?
?
UL-E108898
?
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?
?
New
New
LAN cable (Category-5E)
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Yasuo MIAKE, Univ. of Tsukuba
Electronics & Trigger Issues
Kyoichiro Ozawa
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Yasuo MIAKE, Univ. of Tsukuba
Installation Procedure
Pete Kroon/Edouard Kistenev
• Each half panel, 80
cells, is installed
through the gap from
North and South.
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Yasuo MIAKE, Univ. of Tsukuba