Experiments and Detectors for Future Hadron Colliders

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Experiments and Detectors for Future Hadron
Colliders

• John Womersley
• International Workshop on Future Hadron Colliders
• Fermilab
• October 2003

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Outline

• The organizers asked me to start to list the work
  that needs to be done
• Opportunities
• Problems
• with the idea that we follow up at future
  workshops
• I will summarize
• Work needed on Detector and Accelerator RD
• Work needed on the Political Context
• Importance emphasized by many speakers
• End with some springboards for discussion

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Physics Simulations
Mangano
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Two RD tracks 1

• Targeted RD for SLHC
• Environment can be predicted
• Requirements can be specified
• Challenges are straightforward to enumerate
• Extrapolation from present techniques is
  unavoidable given the timescale
• Organized (funded?) through CERN, ATLAS and CMS

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SLHC Accelerator
Peggs

• Work underway
• In context of LARP in US
• Only Intersection Region upgrades are on the
  table

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SLHC Tracking
Demina

• Challenges
• radiation damage
• occupancy
• Move known techniques further out in radius
• Need new technology for innermost layers (r lt 20
  cm)
• Most likely entire CMS and ATLAS trackers will
  need replacement
• Projects are now underway
• RD50 and RD42
• Better understand radiation damage, materials and
  defects
• Explore new materials
• Electronics issues
• Device engineering, integration issues

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Calorimetry at SLHC
Freeman

• Rate
• Radiation damage
• Activation
• Both ATLAS and CMS
• Barrels OK
• Endcaps need replacement(?)
• Technology exists but not fully worked out
• How much pseudorapidity coverage is needed
• Physics question forward jet tagging

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Muon measurement at SLHC
Taylor

• Critical Issues
• Rate demand on tracking trigger technologies
• Occupancy vs. pattern recognition
• Ghost tracks Track Matching between ID Muons
• Trigger PT resolution Rate
• Stability of chamber parameters under rate
• Beam crossing timing
• Longevity
• Chambers Electronics (Rad Hard SE Upsets)
• Shielding
• Looks as if both ATLAS and CMS will need to
  replace barrel drift tubes
• Gaseous detectors are the only way(?) to cover
  the area needed
• Technology candidates exist

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SLHC Trigger and DAQ
Lankford

• Trigger rates OK
• RD needed on
• New First Level Triggers for
• 12.5 ns crossings
• new sub-detectors
• increased pile-up occupancy
• Data links
• HLT/DAQ networks
• 'Complexity handling'
• Development of commodity computing
• Helps us a great deal, but will it save us?
• Can we learn from management techniques used in
  other big, complex technical integration
  projects?

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VLHC scope

• Are we ready to define energy, luminosity for a
  preferred VLHC?
• Probably not
• Should we explore additional energy, luminosity
  scenarios?
• We have one worked out case from Peter and
  collaborators
• Explore others to better understand parameter
  space?
• What is the process to define what we will
  need/want?
• What is the balance between having a cast-iron
  physics case and making an appeal to throw
  deep, to the excitement of a bold technological
  step?
• e.g. Big telescopes

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Two RD Tracks 2

• Blue sky RD for future machines
• Importance of devoting significant resources to
  this second kind of RD stressed by many speakers
• the requirements cannot be precisely specified
• B tagging?
• Pseudorapidity coverage?
• Need to think of enabling technologies rather
  than developing devices for particular tasks
• Not limited to VLHC application
• e.g. large, cheap detectors help neutrino
  experiments too
• Extrapolation from present techniques may be very
  wrong
• Think outside the box
• Organized how? Funded how?
• The good news is that, if detector issues of
  SLHC are solved, the challenges to go on to VLHC
  seem (to me) relatively tractable
• ?10 in energy is easier than ?10 in luminosity
• Except for the cost of a new tunnel and new
  magnets

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VLHC accelerator RD
Limon

• RD for
• tunneling
• vacuum
• both high and low field magnets
• Very high fields (gt 12 T) may not be the best
  solution
• Synchrotron radiation issues
• Need to demonstrate feasibility, reduce cost

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Tracker/muon issues for VLHC
Denisov Hauser

• Radiation dose, number of pileup tracks and
  pileup energy are all much more dependent on
  luminosity than on ?s
• Specific challenge for VLHC is measuring higher
  energy physics objects (20 TeV muons, for
  example)
• Tracking momentum resolutions ?/BL2
• High field
• Precision measurements
• Large detectors
• Detectors that see only straight tracks or tracks
  coming from the inside
• Otherwise muon triggers get swamped by
  backgrounds
• remember Nikolai Mokhovs pictures
• Affordable, fast, large-area detectors (a better
  RPC)?

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Calorimetry at VLHC
Freeman

• Easier than tracking
• Size ln s, and resolution only gets better with
  energy
• Specific challenge for VLHC is the desire to
  cover very large ? (huge radiation dose)
• Understanding of pileup, missing ET, jet
  resolutions (QCD effects vs. energy flow)
• RD on
• Cerenkov calorimetry (quartz or gas)
• Rad hard and fast
• New photon detectors, rad hard, small, cheap
• New scintillator materials
• Are there totally new detector ideas?

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VLHC probes the deep unknown

• A very large hadron collider was the only
  facility discussed (e.g. at Snowmass 2001) able
  to go so far beyond the energy regime we
  understand that we have no idea what physics we
  will see
• Once upon a time, this would have been exciting,
  compelling, reason enough to build it
• Now it is seen as a liability
• Shouldnt we try to turn this perception around?

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• An LHC experiment
• Study the new interaction with precision
  measurements of Higgs properties at a LC yes,
  good
• but then
• We will want to study the new interaction at much
  higher energies a (V)VLHC experiment

• s 1 TeV
• A new interaction
• We parameterize it as a Higgs

• s 20 TeV?
• see the underlying dynamicsof the WW interaction
• Deep inelastic WW scattering

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Political next steps

• Need to lay the groundwork for future big
  accelerator projects
• Ten years ago to the month, the future of US high
  energy physics was cancelled.
• We have not yet emerged from that shadow
• At least in the U.S., the case for any future
  accelerator is far from made
• We have to work on this no one else will!
• Advocate, defend, promote RD on both accelerator
  and detector development for such projects
• Support the most rapid possible progress on the
  Linear Collider
• Why?
• Because to do otherwise would undermine goal 1
• Because we want a world that can support more
  than one big high-energy physics project
• Because it will do good physics

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Selling accelerators

• Accelerators are the key to understanding this
  weird and wonderful universe that we inhabit
• Only they can provide the
• Controlled conditions
• Known particle species
• High rates
• High energies
• that we need to make sense of cosmological
  observations
• Recent progress in astroparticle physics and
  cosmology strengthens the case for new
  accelerators, it does not weaken it
• no shame in exploiting public interest in these
  discoveries
• The public will relate to
• the unknown
• the cosmos
• big science questions but also to ambitious
  technical projects

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Springboards for discussion

• Does SLHCVLHC in one room make sense? Are we one
  community?
• VLHC Physics
• Do we agree that a staged VLHC is desirable?
• If so, how do we narrow down the parameters of
  stage I?
• When?
• Do we really have the simulation tools that we
  need?
• Is there a catalogue?
• Benchmark processes to cover the bases for
  signals?
• Are we ready for (do we need) a toy detector
  model?
• Developing the physics case
• NASA model of multiple missions within a big
  theme

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Continued

• RD
• How can we promote support for generic detector
  and magnet RD?
• Within this/other laboratories
• FNAL long range planning effort?
• Can we come up with a short list of such projects
  that should be given the highest priority?
• Use this workshop to legitimize them somehow?