Other Opportunities for SLAC

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Other Opportunities for SLAC
SLAC Scenarios Study, Part B P.
Burchat, E. Colby, LD, P. Drell, J. Hewett, T.
Himel, B. Jacobsen, S. Kahn, Y. Karyotakis,
H. Neal, B. Schumm, J. Seeman, D. Su
Scenarios Town Meeting, 11/25/03
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Process Committee surveyed the
major themes in HEP and Particle Astrophysics
Cosmology, decided which themes deserved study
days

• B day (3/20/03) 1036 (or 2 x 1035?) ee- B
  factory
• (Cahn, Hitlin, Seeman, Sullivan)
• Neutrino day (4/18/03) neutrino oscillations,
  n-less double-b decay
• (Kayser, Feldman, Wojcicki, Freedman,
  Prescott)
• LHC day (4/24/03) accel. detector projects for
  lumi. upgrade
• (Strait, DeRoeck, Green)
• Z/Higgs day (5/1/03) gg and ee- machines at E
  lt 250 GeV
• (Gronberg, Raubenheimer, Peskin, Woods)
• Two beam day (5/19/03) additional gg and ee-
  machines
• CLIC RD plasma afterburner
• (Asner, Ruth, Wuensch, Katsouleas)
• Cosmology day (6/13/03) Unveiling dark
  matter/energy
• (Hogan, Linder, Bernstein, Mushotzky)

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• Process (cont.)
• Discussed process future of lab with SLAC
  director
• and former laboratory leadership.
• 7/11/03
• Presented summaries of the days at
• SLUO town meeting, solicited additional input
• from community.
• Met to winnow down options to forward to
• phase II of study.
• Criteria
• Cutting edge science
• Serves/involves user community
• Scope commensurate with national lab, not user
  group
• A 500 GeV LC exists somewhere in world, hence
• dont duplicate
• be realistic about available

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• Dreams Deferred
• What we took off the table, and why
• 2 beam ZH factory ( 10K H/yr, 3B)
  Duplicative of
• 500 GeV LC, too expensive.
• 2 beam Z factory ( 6G Z/yr, 1.5B) Too
  expensive for precision EW physics in the LC
  era.
• gg -gt Higgs shop ( 2K H/yr, 1B) Hgg
  coupling information unique, but little other
  physics. Requires very light Higgs, advances in
  gradients, and significant .
• gg _at_ 30 GeV (200-500M) QCD/2g physics. Pave
  way for higher energy gg collider. Not enough
  HEP interest.
• plasma afterburner for ee- -gt ZH (1K H/yr?,
  ??) Technology still too immature.
• Long baseline n oscillations Much recent
  progress, promising future. However, SLAC role
  unclear
• Accelerator-based experiments require large
  proton drivers. Detector also off-site in
  current plans.
• Many others working on these problems now -gt Stay
  informed.

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• More Dreams Deferred
• reactor ns and qe3 (lt50M) Intriguing quick
  dirty approach to n-mixing, prospects for future
  CP studies.
• Left out as below radar screen.
• megaZ (multi-bunch, mostly S-band, linac,
• ee- -gt Z, 50M Z/yr, 150M(?))
• Substantially reduce ALR, Ab uncertainties. Some
  B physics too.
• X-band portion could serve as LC testbed.
• But
• Incompatible with LCLS unless made much more
  expensive.
• Too late for realistic testbed if LC is on
  track.
• Demand for precision EW measurements in LHC/LC
  era depends
• on type of new physics.
• Should LC be delayed or cancelled, and/or should
  LHC results be puzzling, revisit megaZ, but do
  not include in scenarios.

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• Dreams to Pursue Flavor Physics
• A 2 x 1035 (200M) or 1036 (500M) B factory
• If there is new physics in the quark flavor
  sector, such a machine should be built.
  Complements LHC (e.g. in SUSY,
• LHC sets the overall squark mass scale, B factory
  provides phase, mass splitting information).
• 1036 fully competitive with hadronic B factories
  in Bd decays.
• 2 x 1035 competes in several significant modes.
• In light of physical and fiscal uncertainties,
• keep 4 options open for now
• 0, 2 x 1035, or 1036 at SLAC, or 1036
  at KEK
• (Luminosities refer to post-PEPII upgrade plans
  (3 x 1034).)
• This is the major variable between scenarios.
• Neutrinoless double beta decay Sensitive to
  overall mn,
• Majorana vs. Dirac, lepton number violation
  (leptogenesis).
• If EXO RD successful, project is 50M (plus Xe
  enrichment), small number of SLAC FTEs. Keep in
  all scenarios.

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• Dreams to Pursue Energy Frontier Astro
• Involvement in LHC upgrades LHC is the high
  energy frontier,
• at least until LC turns on. It will remain
  complementary to LC.
• Opportunities for SLAC community to be involved
  in LHC physics by participating in accelerator
  detector upgrades.
• Most likely first upgrade is 10 x luminosity
  upgrade.
• Machine opportunities in this phase include
• RF upgrades to shorten bunch lengths
• RF crab cavities to increase crossing angle
• Major detector challenge is inner tracker,
  particularly
• R lt 20 cm which requires new, very rad hard
  technology.
• Particle Astrophysics Cosmology Kavli
  Institute implies significant involvement here.
  Committee didnt want to identify specific
  projects here, for fear of prematurely tying
  hands of Kavli. But Kavli/SLAC have taken rapid
  steps toward participation in two major cosmology
  projects, SNAP LSST
• (dark matter/energy) projects.
• -gt at least a doubling of current SLAC efforts
  (GLAST).

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• Dreams to Pursue synchrotron light
• Scenarios Committee did not delve into details,
  as there are
• already fairly well-defined opportunities,
  including
• Construction of additional undulator beamlines
  and
• experimental stations for LCLS.
• LCLS-related accelerator RD electron gun,
  lasers, undulators
• Dreams to Pursue future energy frontier
• High Gradient Accelerator RD In the long term,
  it is central to the continued progress of
  accelerator-based HEP.
• Proofs-of-principle underway for plasma laser
  based methods.
• Level of effort should grow, and further engage
  the intellectual capital of the user community.