Liquid Argon Upgrade

1
Liquid Argon Upgrade

• ATLAS SHLC Upgrade organization is in place since
  June 2004
• Goal set by CERN DG upgrade ready for
  commissioning 2012-2014
• ATLAS steering group workplan document
  ATL-GEN-COM-2005-002
• Workshop at CERN on Feb 13 strong support for
  RD work
• Top priority development of new tracker. It
  will be needed by 2010.
• Specialized workshop in Genova in May 2005. (We
  must pay
• attention to the services changes planned for
  inner tracker since
• they coincide with LAr services.
• Next priority Liquid Argon Calorimeter
• Radiation levels Shupe
• Issues of charge collection Oram, Rutherfoord
• Electronics Issues de LaTaille, Farthouat
• Details of machine upgrade not likely to be known
  before 2007

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From Chris de la Taille

• Will not know if front-end boards need
  replacement for a while
• SLHC system specifications needs to be developed
  and agreed.
• Some long term RD issues have to start now.
• LAr RD organization and discussions started
  next step to form working collaborations on
  specific RD issues.
• Expression of interest
• Fast Optical links SMU
• Analog optical links BNL
• Front End Board upgrade Nevis
• Front-end IN2P3 Milano BNL
• Other contributors welcome !
• ( RS impression strong endorsement of issues
  addressed and interest in collaboration)

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US ATLAS LAr constraints

• US ATLAS Research Program budget includes a line
  for Upgrade RD .
• In FY05 Research Program funded 500k for inner
  tracker RD work at six institutions BNL,
  Hampton, LNBL, Santa Cruz, Hawaii, New Mexico.
• In FY06 Research Program will have funds for LAr
  RD work.
• Conditions for funding
• For the next two-three years the goal is to
  identify protential problems that will arrise in
  the upgrade and to find best technologies
  applicable.
• Projects should consider ATLAS constraints
  (e.g., major changes of detector modules geometry
  would require too large disruption of the
  experiment).
• Projects should be endorsed by this group.
• Funding will compete with all other Research
  Program activities computing, physics, MO,
• Lar upgrade RD funding projections are level
  for FY06-FY08.

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US ATLAS LAr constraints 2

• The technologies do not have to be limited to
  those available in Europe. ATLAS management will
  work with the agencies to obtain export
  restriction waivers on any sensitive technology
  product.
• Whenever possible, the RD program should aim at
  maintaining the technical infrastructure needed
  to commission the detector.
• Abe Seiden requested formal proposals to be ready
  in May. They should follow the structure similar
  to that submitted by inner detector groups. All
  proposals will be presented by Seiden to the
  Joint Oversight Group and submitted to the
  Project Office for FY06 funding.
• Each proposal must have schedule, milestones and
  budget.

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US ATLAS LAr constraints 3

• Research Program defined the MO as maintenance
  of the items that were the US Construction
  Project responsibility.
• At present only the upgrade of these items has
  been considered.
• New elements may arrise for SHLC measurement of
  radiation levels, very forward calorimetry,
  luminosity measurement, etc.
• These items represent new scope and should be
  discussed by the ATLAS upgrade steering group
  before any request for US funding. They should be
  sent directly to Abe Seiden.

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Lessons form the present system

• At this early stage of the program it is usefull
  to make a list of lessons learned. My biassed
  list
• Complexity in order to attain the last 5 of
  precission we have a very complex system. We are
  likely to spend 90 of our time on comissioning
  and maintenace of design elements that bring
  small improvements only.
• Example 1 20 different combinations of FEB,
  preamps, tower builders
• Example 2 different chip technologies required
  20 voltage regulators/board
• Question can we simplify the system?
• Redundancy HV design allows for handling
  failures at the module level.
• Question do we need and (if needed) can we
  build-in redundancy in the front-end electronics?
• Goal for the future - top-down system design