Measuring Momentum by TOF for muon cooling development

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Measuring Momentum by TOF for muon cooling
development
Henry Frisch Enrico Fermi Institute, University
of Chicago
INTRODUCTION I got interested in particle ID
so that we could propose a CDF/D0 3rd generation
collider detector at the Tevatron to do physics
BEYOND the LHC frontier via precision
measurements. Needs resolutions 1 psec or so. I
think it can be done (dont know why not
technically(yet)). (politically, P5 needs to wake
up and calculate budgets with no Tevatron.)
Keeping the Tevatron going is the right thing, as
is a muon collider beyond the LHC (ILC is
seriously flawed- the energy is almost certainly
too low given the cost) However, measuring
velocities ltlt 1 when you KNOW the mass is natural
for tof. Idea- 4 stations of TOF- 2 before
cooling, 2 after, measure position and time in
each gt get direction, velocitygt p
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My Motivation- Following the quarks

• A substantial fraction of the HEP community has
  converged on a small number of collider
  experiments- Atlas, CMS, ILC
• Budget gt 1 billion /year
• Output is 3-vectors for most particles, plus
  parton type (e,mu,tau,b,c,..) for some- there is
  still some fundamental information we could get,
  and need.
• Worth the investment to identify the kaons,
  charmed particles, bs, - go to 4-vectors.
  Nothing more left for charged particles!
• Possible other application- photon-vertexing. Add
  converter in front- know velocity, with
  transit-time vertex photons. (e.g. H-gtgg, LHCb,
  K-gtp n n).
• Serious long-term detector RD will pay off in
  many fields- one example- H. Nicholson- proposed
  use of high-res time/pos in DUSEL water-Cherenkov
  full coverage. Great education for young folks
  too

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T979 People/Institutions

• Argonne National Laboratory
• John Anderson, Karen Byrum, Gary Drake, Ed May
• University of Chicago
• Camden Ertley, Henry Frisch, Heejong Kim,
  Jean-Francois Genat, Andrew Kobach, Tyler Natoli,
  Fukun Tang, Scott Wilbur
• Fermilab
• Michael Albrow, Erik Ramberg, Anatoly Ronzhin,
  Greg Sellberg
• Hawaii- Gary Varner
• Saclay/IRFU
• Emilien Chapon,
• Patrick LeDu,
• Christophe Royon
• SLAC
• -Jerry Vavra

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Measuring Momentum by TOF
dp/dtg2 dt/t Goal dt 1-2 psec
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Major advances for TOF measurements
Micro-photograph of Burle 25 micron tube- Greg
Sellberg (Fermilab)

• 1. Development of MCPs with 6-10 micron pore
  diameters

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Idea 1 Generating the signal

• Use Cherenkov light - fast

Incoming rel. particle
Custom Anode with Equal-Time Transmission Lines
Capacitative. Return
A 2 x 2 MCP- actual thickness 3/4 e.g. Burle
(Photonis) 85022-with mods per our work
Collect charge here-differential Input to 200 GHz
TDC chip
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Simulation and Measurement

• Have started a serious effort on simulation to
  optimize detectors and integrated electronics
• Use laser test-stands and MTEST beam to develop
  and validate understanding of individual
  contributions- e.g. Npe, S/N, spectral response,
  anode to input characteristics,
• Parallel efforts in simulating sampling
  electronics (UC, Hawaii) and detectors
  (UC,Saclay, Tom Roberts/Muons.inc).

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FY-08 Funds ANLLaser Test Stand at Argonne
Hamamatsu PLP-10 Laser (Controller w/a laser
diode head) 405 635nm head. Pulse to pulse
jitter lt 10psec (Manufacture Specs)
Electronics
Lens to focus beam on MCP
Diaphram with shutter to next box
MCP 2
Mirrors to direct light
Mirrors to delay light
50/50 beam splitter
X-Y Stager
Laser Head
MCP 1
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Argonne Laser Lab

• Measure Dt between 2 MCPs (i.e root2 times s)
  no corr for elect.
• Results 408nm
• 7.5ps at 50 photoelectrons
• Results 635nm
• 18.3ps at 50 photoelectrons

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Understanding the contributing factors to 6 psec
resolutions with present Burle/Photonis/Ortec
setups- Jerry Vavras Numbers

• TTS 3.8 psec (from a TTS of 27 psec)
• Cos(theta)_cherenk 3.3 psec
• Pad size 0.75 psec
• Electronics 3.4 psec

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Work in Progress

• Our way of proceding- use laser test-stand for
  development, validation of simulation- then move
  to testbeam for comparison with simulation with
  beam.
• Changes to electronics readout
• Add Ritt and/or Varner sampling readouts
  (interleave 10 GS) in works
• First test via SMA then integrate chips onto
  boards?
• Development of 40 GS CMOS sampling in IBM 8RF
  (0.13micron)- proposal in draft (ANL, Chicago,
  Hawaii, Orsay, Saclay)
• Changes to the MCPs
• 10um pore MCPs (two in hand)
• Transmission-line anodes (low inductance-
  matched)- in hand
• Reduced cathode-MCP_IN MCP_OUT-anode gaps-
  ordered
• ALD module with integrated anode and capacitive
  readout- proposed (ANL-LDRD)

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Get position AND timeAnode Design and
Simulation(Fukun Tang)

• Transmission Line- readout both endsgt pos and
  time
• Cover large areas with much reduced channel
  account.

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Expected PerformanceAnode Design and
Simulation(Fukun Tang)

• Transmission Line- simulation shows 3.5GHz
  bandwidth- 100 psec rise (well-matched to MCP)
• Board has been made-

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Atomic Layer Deposition

• ALD is a gas phase chemical process used to
  create extremely thin coatings.
• Current 10 micron MCPs have pore spacing of
  10,000 nm. Our state of the art for Photonis MCPs
  is 2 micron (although the square MCPs are 10
  micron).
• We have measured MCP timing resolution and know
  it depends strongly on pore size, and should
  improve substantially with smaller pores.
• M.Pellins group routinely purchase 60nm
  micro-channel pores and using ALD have achieved
  10nm (this is the state of the art)

M.Pellin, MSD
Karen Byrum slide, mostly
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Psec Large-area Micro-Channel Plate Panel (MCPP)-
LDRD proposal to ANL (with Mike Pellin/MSD)
Front Window and Radiator
Photocathode
Pump Gap
Low Emissivity Material
High Emissivity Material
Normal MCP pore material
Gold Anode
50 Ohm Transmission Line
Rogers PC Card
Capacitive Pickup to Sampling Readout
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FY-08 Funds ChicagoAnode Design and
Simulation(Fukun Tang)
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Electronics Simulation-development of
multi-channel CMOS readout
S/N80 ABW 1 GHz Synthesized MCP signal 8 bit
A-to-D
Jean-Francois Genat
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Electronics Simulation- Samplinganalog bandwidth
on input at fixed S/N and sampling/ABW ratio
S/N80 Synthesized MCP signal 8 bit A-to-D
Time (fs)
Resolution in femtosec (!)
Jean-Francois Genat
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Jerrys s re-visited Solutions to get to
ltseveral psec resolution.

• TTS 3.8 psec (from a TTS of 27 psec)
• MCP development- reduce TTS- smaller
  pores, smaller gaps, filter chromaticity, ANL
  atomic-deposition dynodes and anodes.
• Cos(theta)_cherenk 3.3 psec
  
• Same shape- spatial distribution (e.g.
  strips measure it)
• 3. Pad size 0.75 psec-
  
  Transmission-line readout and shape
  reconstruction
• 4. Electronics 3.4 psec
  
  fast sampling- should be able to get lt
  1psec (simulation)

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Muon Cooling position/time station design- LDRD
(ANL) proposal
H.Frisch
Cartoon drawings showing the custom atomic-layer
disposition, the small pores, and the custom
anode configuration (left) and our proposed
module frame (right)
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Summary

• Next step is to make anodes that give both
  position and time- hope is few mm and ltlt 10 psec
  resolutions. This would allow systems of (say)
  6 by 6 size with 100 channels- good first
  step.
• Muon cooling is a nice first application of psec
  tof- not to big, very important, savings of
  money.
• We have made a number of false starts and wrong
  turns (e.g. the IBM bipolar 200 GHz electronics),
  but the fundamentals look good- dont see a hard
  limit yet.
• Have formed an international community- 2
  workshops per year (France and Chicago)- includes
  companies (Photonis, Photek, IBM)
• Work to be done specifically for muon cooling-
  specify a system. Will be easier after testing
  next round of anodes. Also needs the sampling
  chips.

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Thats All
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C haracteristics we need

• Feature size lt 300 microns
• Homogeneity (ability to make uniform large-area)
• Fast rise-time and/or constant signal shape
• Lifetime (rad hard in some cases, but not all)
• System cost ltlt silicon micro-vertex system

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K-Pi Separation over 1.5m
Assumes perfect momentum resolution (time res is
better than momentum res!)
1 Psec
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Engineering Highlights

• F.Tang (UChicago) designed Voltage Control
  Oscillator using IBM 0.13um SiGe BiCMOS8HP
• More challenging - Time Stretcher chip (including
  ultra low timing jitter/walk discriminator
  dual-slope ramping time stretching circuits etc.)
• From simulations, accuracy not good enough (5-10
  psecs) F.Tang
• Power concerns
• NEW Invented 2 new schemes - a) Multi-threshold
  comparators, b) 50 GHz 64-channel waveform
  sampling. Both schemes give energy and leading
  edge time.
• Current plan Save waveform and use multiple
  thresholds to digitize. Use CMOS (J.F. Genat,
  UChicago)
• Dec meeting at UChicago with UChicago, ANL,
  Saclay, LBL Hawaii, IBM and Photonis

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MCP Best Results

• Previous Measurements
• Jerry Vavra SLAC (Presented at Chicago Sep 2007)
• Upper Limit on MCP-PMT resolution s MCP-PMT 5
  ps
• Takayoshi Ohshima of University of Nagoya
  (Presented at SLAC Apr 2006)
• Reached a s MCP-PMT 6.2ps in test beam

• Using two 10 um MCP hole diameter
• PiLAS red laser diode (635 nm)
• 1cm Quartz radiator (Npe 50)

Burle/Photonis MCP-PMT 85012-501 (64 pixels,
ground all pads except one)

• Use 2 identical 6 micron TOF detectors in beam
  (Start Stop)
• Beam resolution with qtz. Radiator (Npe 50)

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RD of MCP-PMT Devices

• We are exploring a psec-resolution TOF system
  using micro-channel plates (MCP's) incorporating
  
• A source of light with sub-psec jitter, in this
  case Cherenkov light generated at the MCP face
  (i.e. no bounces) Different thicknesses of
  Quartz Radiator
• Short paths for charge drift and multiplication
  Reduced gap
• A low-inductance return path for the
  high-frequency component of the signal
• Optimization of the anode for charge-collection
  over small transverse distances
• The development of multi-channel psec-resolution
  custom readout electronics directly mounted on
  the anode assembly ASIC, precision clock
  distribution
• Smaller pore size Atomic Layer Deposition

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