Muon to Electron Conversion Mu2e Neutrinoless, coherent conversion in the field of a nucleus An exam

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Muon to Electron Conversion- Mu2e Neutrino-less,
coherent conversion in the field of a nucleusAn
example of Charged Lepton Flavor Violation
(CLFV)Status Rme G(m- A-gte-A)/G(m-A-gtnmA)lt7x10-
13(SINDRUM II)Proposed for Fermilab (or JPARC,
or?) Rmelt10-16
Jim Miller Boston University

• SM prediction, from neutrino mixing, is far
  below experimental accessibility
• --gt no SM background
• Discovery of CLFV unambiguous evidence of
  physics beyond SM
• Current limits on CLFV already provide severe
  constraints on models beyond SM
• CLFV processes occur in nearly all scenarios for
  physics beyond the SM
• In many cases the physics reach goes well beyond
  that of direct searches

• MEG Experiment at PSI now constructing an
  experiment to measure the related
• reaction m-gteg, with the goal BR10-13.
• Mu2e(at 10-16) will be 3x more sensitive than
  MEG (at 10-13) for photon mediated
• processes, and 1000x more sensitive for most
  other types of non-SM contributions.

Leptoquarks ML3000 (lmdled)1/2 TeV/c2
SUSY predictions at 10-15

• mA-gteA has a tremendous reach to Lc3000 TeV
  (for Rme10-16) and has the possibility to go
  further ( Rme10-18 to ??) with upgrades in beam
  and detector
• If m-gteg is observed, then mA-gteA is
  complementary, and is unique in its ability to
  help sort out the source of CLFV through
  inteference effects in different targets
• If LHC sees SUSY, mA-gteA is needed to sort out
  LFV

MZ3000 TeV/c2
Compositeness LC3000 TeV

• Representing the Mu2e Steering Group Boston U,
  BNL, Fermilab, NYU, UC-Berkeley, UC-Irvine,
  Osaka, Syracuse, UMASS, UVA

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Experimental Approach

• Stop m- in matter, form atom in 1s state in less
  than 10-16 seconds
• 3 main reactions capture, m-A-gtnmA, decay,
  m--gte-nn, conversion, m-A-gte-A
• Case of aluminum (nuclear capture rate)
  (decay rate), lifetime 0.9 ms
• Conversion process is special mA? eA has big
  experimental advantages
• monenergetic electron (105 MeV) energy far from
  most background
• high rates are possible- no coincidence is
  required (contrast with m-gteg)
• Use pulsed muon beam, spacing 1-2 ms, dictated
  by muonic atom lifetime
• To reach goal G(m- A-gte-A) / G(m-A-gtnmA) lt 10-16
  need 4x1020 protons, 1018
• muons, 2-4 years running with 10-20 of
  beam at FNAL
• Following MECO Develop high-flux muon source and
  a special detector arrangement to minimize
  background

• Physics case, technical feasibility, design have
  successfully passed many reviews.
• Conceptual designs and intial costing for MECO
  are done
• Good beam concept at FNAL has been identified
  with minimal disruption of the planned neutrino
  program
• Recent meeting at FNAL drew 50 scientists.
  Physics case and interest is strong.
• Not asking nuclear physics to support entire
  experiment several nuclear groups have shown
  interest in the project- need nuclear support for
  these groups
• Fermilab director encourages LOI in 2007,
  detailed design work on proton source
• Ideas for a next version which could reach Rme
  10-18 or better with higher muon fluxes- JPARC??

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END
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Muon to Electron ConversionAn example of Charged
Lepton Flavor Violation (CLFV)StatusRme G(m-
A-gte-A)/G(m-A-gtnmA)lt7x10-13Proposed for Fermilab
(or JPARC, or?) Rmelt10-16

• SM prediction, from neutrino mixing, is far
  below experimental accessibility
• --gt no SM background
• Discovery of CLFV unambiguous evidence of
  physics beyond SM
• Current limits on CLFV already provide severe
  constraints on models beyond SM
• CLFV processes occur in nearly all scenarios for
  physics beyond the SM

• Related reaction m-gteg, BR300-400 times more
  sensitive than mA-gteA for
• photon-mediated CLFV, but same sensitivity for
  most other intermediate states.
• MEG (PSI) plans m-gteg measurement to 10-13.
  Phase II MEG 2x10-14?
• May be m-gteg experimental limit. -gt at 10-16
  mA-gteA is 3x more sensitive for photon-
• mediated, 1000x for most other intermediate states

• If MEG sees m-gteg, then mA-gteA unique in its
  ability to help sort out source of CLFV by
  changing
• target nuclei and seeing interference
• If LHC sees SUSY, mA-gteA is needed to sort out
  LFV

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Leptoquarks ML3000 (lmdled)1/2 TeV/c2
SUSY predictions at 10-15
Compositeness LC3000 TeV
MZ3000 TeV/c2
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Muon to Electron Conversion- Mu2e Neutrino-less,
coherent conversion in the field of a nucleusAn
example of Charged Lepton Flavor Violation
(CLFV)Status Rme G(m- A-gte-A)/G(m-A-gtnmA)lt7x10-
13(SINDRUM II)Proposed for Fermilab (or JPARC,
or?) Rmelt10-16
Jim Miller Boston University

• SM prediction, from neutrino mixing, is far
  below experimental accessibility
• --gt no SM background
• Discovery of CLFV unambiguous evidence of
  physics beyond SM
• Current limits on CLFV already provide severe
  constraints on models beyond SM
• CLFV processes occur in nearly all scenarios for
  physics beyond the SM
• In some cases the physics reach goes well beyond
  the reach of direct searches

• Related reaction m-gteg, BR300-400 times more
  sensitive than mA-gteA for
• photon-mediated CLFV, but same sensitivity for
  most other intermediate states.
• MEG (PSI) plans m-gteg measurement to 10-13.
  Phase II MEG 2x10-14?
• (This may be the best that m-gteg experiment can
  ever do.) mA-gteA at 10-16 is
• comparable to phase II for photon- mediated,
  1000x for most other intermediate states

Leptoquarks ML3000 (lmdled)1/2 TeV/c2
SUSY predictions at 10-15

• If MEG sees m-gteg, then mA-gteA is complementary
  and unique in its ability to help sort out source
  of CLFV by changing target nuclei and seeing
  interference effects
• If MEG does not see CLFV, then power of mA-gteA
  needed to reach lc3000 TeV (for Rme10-16) and
  beyond (for Rme10-18 to ??)
• If LHC sees SUSY, mA-gteA is needed to sort out
  LFV

MZ3000 TeV/c2
Compositeness LC3000 TeV

• Representing the Mu2e Steering Group Boston U,
  BNL, Fermilab, NYU, UC-Berkeley, UC-Irvine,
  Osaka, Syracuse, UMASS, UVA