28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics Frascati, Italy 1 Why do we need a super tau/charm factory? David Asner Carleton University

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 2  -charm Physics Topics Charm Mesons –Absolute Branching Fractions –CKM Physics –Dalitz Plots –Rare Decays –Charm Mixing –CP Violation Charm Baryons –  c Absolute Branching Fractions –Form Factors Precision R scan Charmonia –Study of J/ ,  ’,  cj –Y(4260),  (4160),  (4040)Tau –Tau mass –Absolute BF –Dipole moments –Lifetime –CPT, CPV –Lepton universality –Lepton flavor violation –m s,V us

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 3  -charm Physics Topics Charm Mesons –Absolute Branching Fractions –CKM Physics –Dalitz Plots –Rare Decays –Charm Mixing –CP Violation Charm Baryons –  c Absolute Branching Fractions –Form Factors Precision R scan Charmonia –Study of J/ ,  ’,  cj –Y(4260),  (4160),  (4040)Tau –Tau mass –Absolute BF –Dipole moments –Lifetime –CPT, CPV –Lepton universality –Lepton flavor violation –m s,V us X No compelling reason to run at  -threshold   ~   ~ 1nb

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 4  -charm Physics Topics Charm Mesons –Absolute Branching Fractions –CKM Physics –Dalitz Plots –Rare Decays –Charm Mixing –CP Violation Charm Baryons –  c Absolute Branching Fractions –Form Factors Precision R scan Charmonia –Study of J/ ,  ’,  cj –Y(4260),  (4160),  (4040)Tau –Tau mass –Absolute BF –Dipole moments –Lifetime –CPT, CPV –Lepton universality –Lepton flavor violation –m s,V us X No compelling reason to run at  -threshold   ~   ~ 1nb Precision results from BESIII, Radiative B-factory

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 5  -charm Physics Topics Charm Mesons –Absolute Branching Fractions –CKM Physics –Dalitz Plots –Rare Decays –Charm Mixing –CP Violation Charm Baryons –  c Absolute Branching Fractions –Form Factors Precision R scan Charmonia –Study of J/ ,  ’,  cj –Y(4260),  (4160),  (4040)Tau –Tau mass –Absolute BF –Dipole moments –Lifetime –CPT, CPV –Lepton universality –Lepton flavor violation –m s,V us X No compelling reason to run at  -threshold   ~   ~ 1nb Precision results from BESIII, Radiative B-factory X Data at  c threshold CLEO-c won’t BESIII can’t Learn a lot at  (4S)

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 6  -charm Physics Topics Charm Mesons –Absolute Branching Fractions –CKM Physics –Dalitz Plots –Rare Decays –Charm Mixing –CP Violation Charm Baryons –  c Absolute Branching Fractions –Form Factors Precision R scan Charmonia –Study of J/ ,  ’,  cj –Y(4260),  (4160),  (4040)Tau –Tau mass –Absolute BF –Dipole moments –Lifetime –CPT, CPV –Lepton universality –Lepton flavor violation –m s,V us X No compelling reason to run at  -threshold   ~   ~ 1nb Precision results from BESIII, Radiative B-factory X Data at  c threshold CLEO-c won’t BESIII can’t Learn a lot at  (4S) Enormous BESIII J/  sample will provide some answers & open more questions in QCD + Flexibility to directly scan regions of interest: Y(4260)

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 7  -charm Physics Topics Charm Mesons –Absolute Branching Fractions –CKM Physics –Dalitz Plots –Rare Decays –Charm Mixing –CP Violation Charm Baryons –  c Absolute Branching Fractions –Form Factors Precision R scan Charmonia –Study of J/ ,  ’,  cj –Y(4260),  (4160),  (4040)Tau –Tau mass –Absolute BF –Dipole moments –Lifetime –CPT, CPV –Lepton universality –Lepton flavor violation –m s,V us X No compelling reason to run at  -threshold   ~   ~ 1nb Precision results from BESIII, Radiative B-factory X Data at  c threshold CLEO-c won’t BESIII can’t Learn a lot at  (4S) Enormous BESIII J/  sample will provide some answers & open more questions in QCD + Flexibility to directly scan regions of interest: Y(4260) CKM Physics: CLEO-c will measure/enable 1-few % measurement of V cd, V cs, V ub, V cb, V td, V ts BESIII will improve further No Standard Model “hypothesis driven” motivation for further running at charm threshold CLEO-c/BESIII will obtain “interesting” mixing and rare decay results – so will (Super) B-factory

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 8  -charm Physics Topics Charm Mesons –Absolute Branching Fractions –CKM Physics –Dalitz Plots –Rare Decays –Charm Mixing –CP Violation Charm Baryons –  c Absolute Branching Fractions –Form Factors Precision R scan Charmonia –Study of J/ ,  ’,  cj –Y(4260),  (4160),  (4040)Tau –Tau mass –Absolute BF –Dipole moments –Lifetime –CPT, CPV –Lepton universality –Lepton flavor violation –m s,V us X No compelling reason to run at  -threshold   ~   ~ 1nb Precision results from BESIII, Radiative B-factory X Data at  c threshold CLEO-c won’t BESIII can’t Learn a lot at  (4S) Enormous BESIII J/  sample will provide some answers & open more questions in QCD + Flexibility to directly scan regions of interest: Y(4260) Results from LHC will motivate searches at Super B-factory. Results will constrain models Similary LHC results will motivate searches at Super charm factory More importantly connecting (some) precision B Results with LHC results requires precision theory. Super charm factory provides data to test/hone required theoretical techniques

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 9 What’s in a name? We have been asked to consider –Super  -charm factory –Super B-factory Given cross sections & available physics better names are –Super charm factory –Super  -B factory A single machine with energy flexibility –Super flavor factory (SFF)

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 10 Energy Flexibility Since 2000 CESR has run at 100+ different energies –scans of  (1-3S) resonances and  b, D s regions –“on resonance”  (1-5S),  ’,  ’’, 4.17GeV, Y(4260) –“continuum” data near  (1-4S),  ’, 7-10 GeV Energy flexibility reaps scientific fruit –CLEO-c 140 scientists, 21 institutions –Since 2000 ~130 papers in Phys. Rev. Lett. & Phys. Rev. D Problem: Neither CLEO detector nor CESR machine were designed for charm energy running –Luminosity is 5x lower than anticipated from energy scaling –No muon ID at lower energies, Detector not quite optimal

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 11 Choose a single energy e+e- machine to accompany LHC First choice Second choice Third choice Best choice

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 12 Choose a single energy e+e- machine to accompany LHC First choice –ILC Second choice Third choice Best choice

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 13 Choose a single energy e+e- machine to accompany LHC First choice –ILC Second choice –Super tau-B factory Third choice Best choice

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 14 Choose a single energy e+e- machine to accompany LHC First choice –ILC Second choice –Super tau-B factory Third choice –Super charm factory Best choice

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 15 Choose a single energy e+e- machine to accompany LHC First choice –ILC Second choice –Super tau-B factory Third choice –Super charm factory Best choice :not a single energy machine –Super flavor factory (SFF)

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 16 Skeleton Run Plan for SFF CLEO-c & BESIII data samples INSUFFICIENT to fully exploit LHC + Super  -B factory data Beyond Standard Model Studies from Charm –Precision CKM Physics –Dalitz Plots – for  /  3 and more –Rare Decays –Charm Mixing All of above point to 1:100 ratio of  (3770):  (4S) effective integrated luminosity Luminosity + energy spread –~15%  (3770), ~85%  (4S)

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 17 Original Question Why do we need a super tau/charm factory?

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 18 First Answer Why do we need a super tau/charm factory? We do NOT need a super charm factory INSTEAD of a super  -B factory

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 19 Second Answer Why do we need a super tau/charm factory? We do NOT need a super charm factory INSTEAD of a super  -B factory It would be beneficial to have some charm threshold data (1% of luminosity) in ADDITION to b threshold data

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 20 Final Solution Super Flavor Factory

28 Feb – 3 Mar, 2006 Discoveries in Flavour Physics, Frascati, Italy 21 Final Solution Energy flexibility for both Machine and Detector should be included in initial design Super Flavor Factory