J. Brau - ICHEP 2004 - R&D for Future Detectors 1 R&D
for Future Detectors Detector R&D continues on many fronts
Future Detectors will include: Neutrino detectors Massive, high
efficiency Hadron B Factory, Rare Kaon Decay, /Charm Detectors High
bandwidth, high precision Linear Collider Detectors Precision
measurements I will concentrate on the Linear Collider Detector
R&D Slide 2 J. Brau - ICHEP 2004 - R&D for Future Detectors
2 Linear Collider Detector Requirements Both Physics and
Accelerator Constraints dictate the Detector Requirements Linear
Collider creates new challenges and opportunities, different in
many respects from the challenges and opportunities of the LHC
detectors Physics motivates Triggerless event collection (software
event selection) Extremely precise vertexing Synergistic design of
detectors components: vertex detector, tracker, calorimeters
integrated for optimal jet reconstruction New technologies based on
recent detector inventions Detector R&D of Next Few Years is
Critical Slide 3 J. Brau - ICHEP 2004 - R&D for Future
Detectors 3 Collider Constraints Linear Collider Detector R&D
has had to consider two different sets of collider constraints:
X-Band RF and Superconducting RF designs With the linear collider
technology selection, the detector efforts can concentrate on one
set of parameters The ILC creates requirements similar to those of
the TESLA design X-BandGLC/NLCSuperRFTESLA #bunch/train1922820
#train/sec150/1205 bunch spacing 1.4 nsec 337 nsec
bunches/sec28800/2304014100 length of train 269 nsec 950 sec train
spacing 6.6/8.3 msec 199 msec crossing angle 7-20 mrad 0-20 mrad
Slide 4 J. Brau - ICHEP 2004 - R&D for Future Detectors 4
Linear Collider Events Simple events (relative to Hadron collider)
make particle level reconstruction feasible Heavy boson mass
resolution requirement sets jet energy resolution goal t t event at
350 GeV Slide 5 J. Brau - ICHEP 2004 - R&D for Future Detectors
5 EM Neutral Hadrons Charged Hadrons Calorimetry Current paradigm:
Particle/Energy Flow (unproven) Jet resolution goal is 30%/ E In
jet measurements, use the excellent resolution of tracker, which
measures bulk of the energy in a jet Particles in Jet Fraction of
Visible Energy DetectorResolution Charged ~65%Tracker< 0.005% p
T negligible Photons ~25%ECAL ~ 15% / E Neutral Hadrons ~10%ECAL +
HCAL ~ 60% / E ~ 20% / E Headroom for confusion Slide 6 J. Brau -
ICHEP 2004 - R&D for Future Detectors 6 Energy/Particle Flow
Calorimetry Follow charged tracks into calorimeter and associate
hadronic showers Identify EM clusters not associated with charged
tracks (gammas) Remaining showers will be the neutral hadrons Slide
7 J. Brau - ICHEP 2004 - R&D for Future Detectors 7 EM
Calorimetry Physics with isolated electron and gamma energy
measurements require ~10-15% / E 1% Particle/Energy Flow requires
fine grained EM calorimeter to separate neutral EM clusters from
charged tracks entering the calorimeter Small Moliere radius
Tungsten Small sampling gaps so not to spoil R M Separation of
charged tracks from jet core helps Maximize BR 2 Natural technology
choice Si/W calorimeters Good success using Si/W for Luminosity
monitors at SLD, OPAL, ALEPH Oregon/SLAC/BNL CALICE Alternatives
Tile-Fiber (challenge to achieve required granularity)
Scintillator/Silicon Hybrid Shaslik Scintillator Strip material
RMRMRMRM Iron 18.4 mm Lead 16.5 mm Tungsten 9.5 mm Uranium 10.2 mm
Slide 8 J. Brau - ICHEP 2004 - R&D for Future Detectors 8
Silicon/Tungsten EM Calorimeter SLAC/Oregon/BNL Conceptual design
for a dense, fine grained silicon tungsten calorimeter well
underway First silicon detector prototypes are in hand Testing and
electronics design well underway Test bump bonding electronics to
detectors by end of 04 Test Beam in 05 Slide 9 J. Brau - ICHEP 2004
- R&D for Future Detectors 9 Silicon/Tungsten EM Calorimeter
(2) Pads ~5 mm to match Moliere radius Each six inch wafer read out
by one chip < 1% crosstalk Electronics design Single MIP tagging
(S/N ~ 7) Timing < 5 nsec/layer Dynamically switchable feedback
capacitor scheme (D. Freytag) achieves required dynamic range:
0.1-2500 MIPs Passive cooling conduction in W to edge Angle
subtended by R M GAP Slide 10 J. Brau - ICHEP 2004 - R&D for
Future Detectors 10 ECAL Prototype 9720 channels in prototype Slide
11 J. Brau - ICHEP 2004 - R&D for Future Detectors 11 Y Y Tilt
X X beam HCAL ECAL DESY late 2004 Preparations for DESY Beam Test
Wafers: Russia/MSU and Prague/IOP PCB: LAL design, production
Korea/KNU Slide 12 J. Brau - ICHEP 2004 - R&D for Future
Detectors 12 Other EM Calorimeters Tile-fiber Interesting readouts,
such as SiPM Option shower max (scintillator strips or silicon
pads) Silicon Photomultiplier Russia, ITEP KEK, Kobe, Konan,
Niigata, Shinshu, Tsukuba Colorado Slide 13 J. Brau - ICHEP 2004 -
R&D for Future Detectors 13 Other EM Calorimeters (2)
Silicon-scintillator Hybrid Scintillator strip Shashlik
Sc-W-Sc-W-Si-W-Sc-W-Sc-W Kansas Como, ITE-Warsaw, LNF, Padova,
Trieste KEK, Kobe, Konan, Niigata, Shinshu, Tsukuba Slide 14 J.
Brau - ICHEP 2004 - R&D for Future Detectors 14 Hadron
Calorimetry Role of Hadron Calorimetry in the Energy/Particle Flow
Isolate and measure neutral hadrons Approaches Technology RPCs
(Note promising work at IHEP-Beijing on oil-less resistive plate)
GEMs Tile-fiber w/ APD SiPM HPD EBCCD Scintillator stripsReadout
Analog Digital high granularity Slide 15 J. Brau - ICHEP 2004 -
R&D for Future Detectors 15 MINICAL Prototype Studied different
readout systems (PM, SiPM, APD) Established reliable calibration
system, checked long term stability, established detailed MC
simulation Developed stability monitoring system In 2005 move to
hadron beam to fully test HCAL performance Hamburg, DESY, Dubna,
MEPhI, Prague, LPI, ITEP Electron resolution in hadron calorimeter
Slide 16 J. Brau - ICHEP 2004 - R&D for Future Detectors 16
Digital Hadron Calorimetry 1 m 3 prototype planned to test concept
Lateral readout segmentation: 1 cm 2 Longitudinal readout
segmentation: layer-by- layer Gas Electron Multipliers (GEMs) and
Resistive Plate Chambers (RPCs) evaluated Objectives Validate RPC
approach (technique and physics) Validate concept of the electronic
readout Measure hadronic showers with unprecedented resolution
Validate MC simulation of hadronic showers Compare with results
from Analog HCAL Argonne National Laboratory Boston University
University of Chicago Fermilab University of Texas at Arlington
Slide 17 J. Brau - ICHEP 2004 - R&D for Future Detectors 17
Tracking Tracking for any modern experiment should be conceived as
an integrated system, combined optimization of: the inner tracking
(vertex detection) the central tracking the forward tracking the
integration of the high granularity EM Calorimeter Pixelated vertex
detectors are capable of track reconstruction on their own, as was
demonstrated by the 307 Mpixel CCD vertex detector of SLD, and is
being planned for the linear collider Track reconstruction in the
vertex detector impacts the role of the central and forward
tracking system Slide 18 J. Brau - ICHEP 2004 - R&D for Future
Detectors 18 Inner Tracking/Vertex Detection Detector Requirements
Excellent spacepoint precision ( < 4 microns ) Superb impact
parameter resolution ( 5m 10m/(p sin 3/2 ) ) Transparency ( ~0.1% X
0 per layer ) Track reconstruction ( find tracks in VXD alone )
Concepts under Development for Linear Collider Charge-Coupled
Devices (CCDs) demonstrated in large system at SLD Monolithic
Active Pixels CMOS (MAPs) DEpleted P-channel Field Effect
Transistor (DEPFET) Silicon on Insulator (SoI) Image Sensor with
In-Situ Storage (ISIS) HAPS (Hybrid Pixel Sensors) Slide 19 J. Brau
- ICHEP 2004 - R&D for Future Detectors 19 Inner
Tracking/Vertex Detection (CCDs) Issues Readout speed and timing
Material budget Power consumption Radiation hardnessR&D Column
Parallel Readout ISIS Radiation Damage Studies SLD VXD3 307 Mpixels
5 MHz 96 channels 0.4% X 0 / layer ~15 watts @ 190 K 3.9 m point
res. av. - 2 yrs and 307 Mpxl Slide 20 J. Brau - ICHEP 2004 -
R&D for Future Detectors 20 Column Parallel CCD SLD Vertex
Detector designed to read out 800 kpixels/channel at 10 MHz,
operated at 5 MHz => readout time = 200 msec/ch Linear Collider
demands 250 nsec readout for Superconducting RF time structure
Solution: Column Parallel Readout LCFI (Bristol, Glasgow,
Lancaster, Liverpool, Oxford, RAL) (Whereas SLD used one readout
channel for each 400 columns) Slide 21 J. Brau - ICHEP 2004 -
R&D for Future Detectors 21 Column Parallel CCD (2) Next Steps
for LCFI R&D Bump bonded assemblies Radiation effects on fast
CCDs High frequency clocking Detector scale CCDs w/ASIC &
cluster finding logic; design underway production this year In-situ
Storage Devices Resistant to RF interference Reduced clocking
requirements Slide 22 J. Brau - ICHEP 2004 - R&D for Future
Detectors 22 Image Sensor with In-situ Storage (ISIS) EMI is a
concern (based on SLC experience) which motivates delayed operation
of detector for long bunch trains, and consideration of ISIS Robust
storage of charge in a buried channel during and just following
beam passage (required for long bunch trains) Pioneered by W F
Kosonocky et al IEEE SSCC 1996, Digest of Technical Papers, 182 T
Goji Etoh et al, IEEE ED 50 (2003) 144; runs up to 1 Mfps. charge
collection to photogate from 20- 30 m silicon, as in a conventional
CCD signal charge shifted into stor. register every 50 s, providing
required time slicing string of signal charges is stored during
bunch train in a buried channel, avoiding charge-voltage conversion
totally noise-free charge storage, ready for readout in 200 ms of
calm conditions between trains for COLD LC design particles which
hit the storage register (~30% area) leave a small direct signal
(~5% MIP) negligible or easily corrected Slide 23 J. Brau - ICHEP
2004 - R&D for Future Detectors 23 neutrons induce damage
clusters low energy electrons create point defects but high energy
electrons create clusters Y. Sugimoto et al. number of effective
damage clusters depends on occupation time some have very long
trapping time constants modelled by K. Stefanov Radiation Effects
in CCDs N. Sinev et al. Drift of charge over long distance in CCD
makes detector very susceptible to effects of radiation: Transfer
inefficiency Surface defects Traps can be filled Expect ~1.5x10 11
/cm 2 /yr of ~20 MeV electrons at layer-1 Expect ~10 9 /cm 2 /yr 1
MeV-equivalent dose from extracted beamline Hot pixels Slide 24 J.
Brau - ICHEP 2004 - R&D for Future Detectors 24 Inner
Tracking/Vertex Detection (MAPs) Concept Standard VLSI chip, with
thin, un-doped silicon sensitive layer, operated
undepletedAdvantages decoupled charge sensing and signal transfer
(improved radiation tolerance, random access, etc.) small pitch
(high tracking precision) Thin, fast readout, moderate price, SoC
R&D Strasbourg IReS has been working on development of
monolithic active pixels since 1989; RAL also now. First IReS
prototype arrays of a few thousands of pixels demonstrated the
viability of technology and its high tracking performances. First
large prototypes now fabricated and being tested. Current attention
focussed on readout strategies adapted to specific experimental
conditions. Parallel R&D: FAPS (RAL) 10-20 storage
capacitors/pixel Technology will be used at STAR Slide 25 J. Brau -
ICHEP 2004 - R&D for Future Detectors 25 Inner Tracking/Vertex
Detection (DEPFET) Properties low capacitance low noise Signal
charge remains undisturbed by readout repeated readout Complete
clearing of signal charge no reset noise Full sensitivity over
whole bulk large signal for m.i.p.; X-ray sens. Thin radiation
entrance window on backside X-ray sensitivity Charge collection
also in turned off mode low power consumption Measurement at place
of generation no charge transfer (loss) Operation over very large
temperature range no cooling neededConcept Field effect transistor
on top of fully depleted bulk All charge generated in fully
depleted bulk; assembles underneath the transistor channel; steers
the transistor current Clearing by positive pulse on clear
electrode Combined function of sensor and amplifier 16x128
DEPFET-Matrix MPI Munich, MPI Halle, U. Bonn, U. Mannheim Slide 26
J. Brau - ICHEP 2004 - R&D for Future Detectors 26 Central
Tracking Two general approaches being developed for the Linear
Collider TPC (or Jet Chamber) Builds on successful experience of
PEP-4, ALEPH, ALICE, DELPHI, STAR, .. Large number of space points,
making reconstruction straight-forward dE/dx particle ID, bonus
Minimal material, valuable for calorimetry Tracking up to large
radii Silicon Superb spacepoint precision allows tracking
measurement goals to be achieved in a compact tracking volume
Robust to spurious, intermittent backgrounds linear collider is not
storage ring Slide 27 J. Brau - ICHEP 2004 - R&D for Future
Detectors 27 Central Tracking (TPC) Issues for LC TPC Optimize
novel gas amplification systems Conventional TPC readout based on
MWPC and pads limited by positive ion feedback and MWPC response
Improvement by replacing MWPC readout with micropattern gas
chambers (eg. GEMs, Micromegas) Small structures (no E B effects)
2-D structures Only fast electron signal Intrinsic ion feedback
suppression Neutron backgrounds Optimize single point and double
track resolution Performance in high magnetic fields Demonstrate
large system performance with control of systematics Slide 28 J.
Brau - ICHEP 2004 - R&D for Future Detectors 28 GEM
Conventional TPC: Wires TPC Gas Amplification System Small
structures (no E B effects) 2-D structures Only fast electron
signal Intrinsic ion feedback suppression New concept for gas
amplification at the end flanges: Replace proportional wires with
Micro Pattern Gas Detectors Gas Electron Multiplier (GEM) - F.
Sauli, 1997 or Micromegas - Y. Giomataris et al., 1996 Also being
investigated: Medipix2, CMOS pixel sensor w/GEM (NIKHEF, Saclay,
Twente/Mesa, CERN) Slide 29 J. Brau - ICHEP 2004 - R&D for
Future Detectors 29 50 m kapton foil, double sided copper coated 75
m holes, 140 m pitch GEM voltages up to 500 V yield 10 4 gas
amplification Use GEM towers for safe operation (COMPASS) Gas
Electron Multiplier (GEM) for TPC Readout 140 m 75 m Slide 30 J.
Brau - ICHEP 2004 - R&D for Future Detectors 30 asymmetric
parallel plate chamber with micromesh saturation of Townsend
coefficient mild dependence of amplification on gap variations ion
feedback suppression 50 m pitch Micromegas for TPC Readout Slide 31
J. Brau - ICHEP 2004 - R&D for Future Detectors 31 TPC
Resolution Studies with Magnetic Field and 1 T at Triumf Slide 32
J. Brau - ICHEP 2004 - R&D for Future Detectors 32 Ion feedback
improves with (GEM) or is independent of (Micromegas) magnetic
field transverse resolution (mm) drift time (50 ns bins) 300 mm30
mm B = 0.9 T B = 0 B = 1.5 T 100 micron TPC Resolution and Ion
Feedback P5 gas Magnetic field improves resolution TPC Resolution
GEM Double-GEM Slide 33 J. Brau - ICHEP 2004 - R&D for Future
Detectors 33 Central Tracking (Silicon) With superb position
resolution, compact tracker is possible which achieves the linear
collider tracking resolution goals Compact tracker makes the
calorimeter smaller and therefore cheaper, permitting more
aggressive technical choices (assuming cost constraint) Linear
Collider backgrounds (esp. beam loss) extrapolated from SLC
experience also motivate the study of silicon tracking detector,
SiD Silicon tracking layer thickness determines low momentum
performance 3 rd dimension may be achieved with segmented silicon
strips, or silicon drift detectors (1.5% / layer) (TPC) Slide 34 J.
Brau - ICHEP 2004 - R&D for Future Detectors 34 Central
Tracking (Silicon) Optimizing the Configuration R. Partridge
Cooper, Demarteau, Hrycyk support H. Park Slide 35 J. Brau - ICHEP
2004 - R&D for Future Detectors 35 Central Tracking (Silicon)
Strip length: Short strips segments (10 cm slices) are interesting
for less noise, shorter shaping time, better time stamping. Longer
strips, long shaping time designs are also under development,
motivated by minimized material in tracking volume. Two ASICs for
long shaping will soon go to fab. Power Off Response to , 1 and 4
mip signals 8 msec power-off period (not to scale) 60 msec power
restorat ion Power On Note, silicon detector R&D also supports
TPC detector where intermediate and forward tracking are needed
LPNHE Preamp Santa Cruz ASIC power cycle Slide 36 J. Brau - ICHEP
2004 - R&D for Future Detectors 36 Silicon Tracking w/
Calorimeter Assist V0 tracks reconstructed from ECAL stubs Primary
tracks started with VXD reconstr. E. von Toerne Slide 37 J. Brau -
ICHEP 2004 - R&D for Future Detectors 37 Very Forward
Instrumentation Hermiticity depends on excellent coverage in the
forward region, and forward system plays several rolesHermiticity
depends on excellent coverage in the forward region, and forward
system plays several roles maximum hermiticity precision luminosity
shield tracking volume monitor beamstrahlung High radiation levels
must be handledHigh radiation levels must be handled 10 MGy/year in
very forward detectors TESLA Goal: L/L: 10 -4 (exp.) L/L: 10 -4
(theo.) Ref: OPAL (LEP) L/L: 3.4 x 10 -4 (exp.) L/L: 5.4 x 10 -4
(theo.) Slide 38 J. Brau - ICHEP 2004 - R&D for Future
Detectors 38 Machine Detector Interface A critical area of detector
R&D which must be optimized is where the detector meets the
collider Preserve optimal hermiticity Preserve good measurements
Control backgrounds Quad stabilization Zero crossing angle, TPC
detector 20 mr crossing angle, silicon detector Slide 39 J. Brau -
ICHEP 2004 - R&D for Future Detectors 39 Detector Beamline
Instrumentation Polarized electrons (and perhaps positrons)
Polarimeter 0.2% goal Electron energy Energy spectrometer 200 ppm
required Beam energy profile Differential luminosity measurement
knowledge of beamstrahlung effects required S. Boogert Slide 40 J.
Brau - ICHEP 2004 - R&D for Future Detectors 40 Other Detector
R&D Efforts Muon Detectors RPCs Scintillator strips w/ MAPMTs
Detector Solenoid All detector concepts under study assume a strong
magnetic field of strength greater than 3T with a coil of large
diameter. The large volume required for this high-field magnet is a
challenge, but experience with the 4T solenoid for CMS will be very
helpful. This experience has been utilized in detector designs, but
requires additional understanding. Need to study compensation
issues if machine has a crossing angle. Quad stabilization
Machine-detector-interface issue crucial for the detector. Slide 41
J. Brau - ICHEP 2004 - R&D for Future Detectors 41 Summary
Linear Collider Experimental Program needs advances in detector
technology specific to the challenges of the LC: High granularity,
high precision, triggerless operation A coordinated, R&D effort
is underway world-wide to develop the advanced detectors needed to
capitalize on the special discovery opportunities which will be
created by the construction of the linear collider. The Detector
community has been preparing, but eagerly awaiting the technology
choice to make the focused R&D program. With the technology
decision, it is now time for a significant ramping up of this
effort.
