Transcript ILC Detector Design Study in Japan Yasuhiro Sugimoto KEK Contents Introduction Overview of ILC detector R&D Requirements for ILC detectors Activities in Japan Detector concept study Sub-detector R&D GLD Detector Outline Document Summary.

ILC Detector Design
Study in Japan
Yasuhiro Sugimoto
KEK
Contents
Introduction
Overview
of ILC detector R&D
Requirements for ILC detectors
Activities
in Japan
Detector
concept study
Sub-detector R&D
GLD Detector Outline Document
Summary
Introduction

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Overview of “Detector R&D” for ILC
Requirements for ILC Detectors
Milestones of ILC
2004
2005
2006
2007
2008
2009
2010
Start Global Lab.
GDE
Acc.
Technology
Choice
BCD
TDR
Done!
(Construction)
WWS
Done!
Det.
RDR
Conceptual design
DODs
Almost
done!
Sub-det. R&D
DCR
cooperation
Priority-1 items
LOIs (?)
Priority-2 items
Only 3 years left for critical R&Ds
GDE: Global Design Effort
WWS: World Wide Study of physics and detector
BCD: Baseline Configuration Document
RDR: Reference Design Report
DOD: Detector Outline Document
DCR: Detector Concept Report
Detector Design Study
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Detector Concept Study
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Conceptual design study of detector systems
3 major concepts + 1 new concept
SiD

LDC
GLD
Sub-detector R&D


More than 60 groups in the world
Usually related with several detector concepts
 Horizontal collaboration
4 th
Requirements for ILC
Detectors
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Physics goal of ILC
 Wide variety of processes
 Energy range: Mz<ECM<1 TeV
Basic requirements
 Reconstruct events at fundamental particle (quark, lepton, gauge
bosons) level
 Efficient identification and precise 4-momentum measurement of
these fundamental particles
ILC detectors should have performances of
 Good jet energy resolution to separate W and Z
 Efficient jet-flavor identification capability
 Excellent charged-particle momentum resolution
 Hermetic coverage to veto 2-photon background
Performance Goal

Jet energy resolution
 ( E j ) / E j  30% / E j (GeV)

 1/2 w.r.t. LHC
Impact parameter resolution for flavor tag
 IP  5 10 / p sin 3/ 2  (m)

 1/2 resolution term, 1/7 M.S. term w.r.t. LHC
Transverse momentum resolution for charged particles
 ( pt ) / pt 2  5105 (GeV/c)1

 1/10 momentum resolution w.r.t. LHC
Hermeticity
 min  5 mrad
Advantage of high
performance detector

Example: Strongly interacting Higgs
e e  W W / ZZ
 


M2qq(GeV)
s  1 T eV
L  1 ab1
30% / E
60% / E
M1qq(GeV)
Projection
to M1=M2
Advantage of high
performance detector

Example: Higgs muon pair decay
ee  ZH , H     



Br(H +-)~3x10-4
O(10) events with L=500 fb-1
The peak above background may be seen with excellent tracker
 ( pt ) / pt 2  1104
s  250GeV
L  1 ab1
M H  120GeV

Activities in Japan

Detector Concept Study
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Sub-detector R&D
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GLD
(SiD)
Vertex detector
TPC
Calorimeter
(Si tracker for SiD)
GLD Detector Outline Document
Detector Concept Study
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GLD – a large gaseous detector
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

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Large radius calorimeter to optimize for PFA
Large radius gaseous tracker (TPC) to get
excellent momentum resolution and pattern
recognition capability
Forward calorimeter down to ~5 mrad
Precision Si micro-vertex detector
Si inner-, forward-, and endcap tracker
Muon detector interleaved with iron return yoke
Moderate solenoid magnetic field of 3 T
GLD
r-f view
z-r view
Vertex detector and Si inner and
forward tracker are not shown
PFA
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
PFA (Particle Flow Analysis) is thought to be a way to get best jetenergy resolution
Measure energy of each particle separately
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Overlap of charged cluster and neutral cluster in the calorimeter
affects the jet-energy resolution
Cluster separation in the calorimeter is important
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Charged particle : by tracker
Gamma : by EM Calorimeter
Neutral hadron : by EM and Hadron Calorimeter
Large Radius (R)
Strong B-field
Fine 3-D granularity ()
Small Moliere length (RM)
Algorithm
Often quoted figure of merit :
BR2
RM   2
2
Simulation Studies for GLD
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Study of PFA (Tohoku, Niigata, KEK, Tsukuba, Tokyo,
Shinshuu, Kobe, Mindanao)
Tracking performance (Tsukuba, KEK, Korea,
Kyungpook, Yonsei)
Impact parameter resolution (Tohoku, Tsukuba,
KEK)
Vertex charge determination (Oxford, RAL)
Background study (Saga, Tokyo, KEK)
Design study of solenoid magnet and return yoke
based on FEA (KEK)
Simulation Study

Study of “cheated PFA”
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Perfect track-calorimeter
matching based on Monte
Carlo truth
Shower fluctuation, particle
interactions with material
fully simulated
 Identify terms contributing
to the resolution to design
the best detector


u,d,s quark pair
Events at Z pole
Simulation Study

Source of resolution in “cheated PFA”
Neutrino
5 mrad cut
Low Pt track
TPC res.
EM Cal res.
HD Cal res.
Total
0.30 GeV
0.62
0.83
0
1.36
1.70
2.48
(require TPC)
Contribution from low pt cut is
significant. Low pt tracking using
only VTX and SIT will be studied.
Simulation Study

Realistic PFA
• Z → qq @ 91.18GeV
~
60%
~
E
~
CAL energy sum
38%
E
PFA
More effort / new idea is necessary to
achieve the goal of 30%/SQRT(E)
60%
E
Simulation Study

Tracking performance
The performance goal
can be achieved with
GLD detector with TPC
of 150m point
resolution
Future plan for concept study

By the end of 2006 (by DCR)
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More detailed detector simulation
More realistic detector design
More precise cost estimate
Towards LOI
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Continue the activity listed above and update the
design based on the outputs of sub-detector R&D
Formation of an experimental group
Sub-detector R&D: VTX
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
KEK, Tohoku, Tohoku-gakuin, Niigata collaboration
Challenges of ILC vertex detector (VTX)
 Very thin wafer ( < 100 m/layer) and excellent point
resolution ( < 3 m) are necessary to achieve the
performance goal
 In order to keep pixel occupancy due to beam
background hits reasonably low, the sensors have to be
read out 20 times/train and very fast readout speed
(>50MHz) is needed, if the pixel size is ~20m
 Experience at SLD tells that readout during train could
cause beam-induced RF pickup problem
 At present, no proven technology exists
Sub-detector R&D: VTX
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Our idea: FPCCD
 By using fine pixel CCDs (FPCCD) with the pixel size of ~5m
and fully depleted epitaxial layer, pixel occupancy can be as low
as <1% even if the signal of one bunch train is accumulated and
read out between trains
R&D status of FPCCD Vertex Detector
 Simulation study of background rejection using hit cluster shape
 Study of charge spread and Lorentz angle in fully depleted CCD
All
dW<10m
Sub-detector R&D: VTX
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Future plan – R&D needed
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Design and development of prototype FPCCDs and
demonstration of the performance
 Readout speed ~ 15 MHz
 Multi port readout
Study of wafer thinning and the support structure
Development of readout ASIC
Sub-detector R&D: TPC
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Saga, Hiroshima, KEK, Kinki, Kogakuin, Mindanao,
TUAT, Tsukuba collaboration (with LCTPC groups)
Challenges of ILC TPC
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High point resolution (<150m) after long drift (>2m)
 MWPC readout  MPGD readout
 Gas choice
Large scale (R~2m) structure
R&D issues
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Study of MPGD: GEM and MicroMEGAS
Study of chamber gas property: drift velocity, diffusion
Positive ion feedback control
High density and low material electronics
Sub-detector R&D: TPC
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R&D activity
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Series of beam tests have
been done at KEK PS using
small size test chamber with
MWPC, GEM, and
MicroMEGAS readout
The activity is international
– with LCTPC groups
 Collaborators from Canada,
France, Germany, Japan,
Philippines joined the BT
Sub-detector R&D: TPC

Results of the beam tests
 Resolution is understood in terms of pad pitch, diffusion, pad
response function, and the effective number of electrons
 To improve resolution, smaller pad size or larger charge width
(resistive anode) is effective
Resolution as a function of drift distance
2.3 mm / 12
Data
 X2   X2 0  D 2 / N eff z
D/
N eff  38.4  9.7 m/ cm
 X 0 129 53 m
Neumerical Calculation
MicroMEGAS
Pad : 2.3 mm
Diffusion Constnat : 193
Neff = 27.5
f :  function
Data: MicroMEGAS
B=1T
Gas: Ar-isobutane (5%)
Pad: 2.3 mm Pads
Sub-detector R&D: TPC

Resolution with resistive anode
4 GeV/c + beam
 ~ 0°, f ~ 0°
 x 2   02 
Cd2  z
N eff
0= (52±1) m
Neff = 220 (stat.)
Sub-detector R&D: TPC
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Future plan of TPC R&D
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Search for better gas mixture and MPGD configuration to
achieve the TPC performance goal
Measurement of pad response function and avalanche
fluctuation using single electrons for better understanding
of spatial resolution
Study of positive ion back flow suppression
Simulation study of MPGD TPC
Performance tests with large prototypes using PCMAG and
prototype electronics under international cooperation
Sub-detector R&D: CAL
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Kobe, Niigata, Shinshu, Tsukuba, Mindanao,
JINR, Korean universities
R&D for scintillator based calorimeter (CAL)
Challenges

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Achieve sufficient granularity with reasonable cost
Optimize the configuration to achieve the
performance goal
Develop best PFA algorithm
Sub-detector R&D: CAL
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Configuration
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EM CAL: TungstenScintillator strip sandwich
Hadron CAL: LeadScintillator strip/tile
sandwich
Wavelength shifting fiber
and MPPC readout for
both CALs
MPPC: Multi Pixel Photon Counter
Sub-detector R&D: CAL

Photon sensor R&D – MPPC
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Merit of MPPC
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Work in Magnetic Field
Very compact and can be
directly mounted on the fiber
High gain (~106) with a low
bias voltage (25~80V)
Photon counting capability at
room temperature
Sub-detector R&D: CAL
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R&D status and plan
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MPPC testing in progress
MPPC R&D : Larger size (1.5mm) and more pixel
(>2000) is necessary
ECAL prototype construction in progress and
beam tests at DESY in 2006 and at FNAL in
2007(?) are planned
Improvement of PFA algorithm is necessary
HCAL beam test is indispensable to understand
hadronic shower
Sub-detector R&D

Future prospects

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Each sub-detector R&D group has future plan (desire) towards LOI
Required funding increases significantly in order to make further
progress, but the established funding level is extremely low in
Japan
Therefore, it is hard to present reliable future prospects now
(For priority-1 items only)
Funding level in each region
for coming 3-5 years
(from “ILC detector R&D status
report and urgent requirements
for funding”, edited by WWS
Detector R&D Panel)
GLD DOD
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GLD concept study and sub-detector R&D activities
are crystallized into “GLD Detector Outline Document”
It consists of the following sections;
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Description of the concept
Detector sub-systems
Physics performances
and a separate document on cost estimate
To be finalized by April 15th
DOD is not the goal. It is a starting point for further
optimization of GLD detector design.
Summary
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Japanese group is actively involved in GLD detector
concept study
There are sub-detector R&D activities in Japan for
vertex detector, TPC, and calorimeter
But future prospects of these activities are not clear
due to lack of established funding
Activities of GLD detector concept study and subdetector R&D are crystallized into “GLD Detector
Outline Document”, which will be published soon
These activities should be continued to make more
optimized and realistic detector design, and more
precise cost estimation