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Super B Factory Physics Impact. David Hitlin SLAC SSI August 5, 2009. Why Super B factories ?.
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Super B FactoryPhysics Impact David Hitlin SLAC SSI August 5, 2009
Why Super B factories ? • The motivation to continue e+e- flavor physics studies with a Super B factory beyond the BABAR/Belle/(LHCb) era lies in its ability to make measurements that have sensitivity to physics beyond the Standard Model • This sensitivity extends to New Physics in b, c and t decay • A data sample of 50-75 ab-1is required to provide this sensitivity • BABAR +Belle total sample is <2 ab-1 • A luminosity in the range of 1036 cm-2s-1 is required to integrate this large a sample in a reasonable time • There are two approaches on the market to acquiring such a sample • SuperKEKB at KEK and SuperB at Rome II Univ (Tor Vergata) or LNF • Both asymmetric colliders now use a version of the “Italian scheme” • Collide asymmetric energy rings having very low emittance, similar to those developed for the ILC damping rings and high brightness light sources • SuperB also employs a new type of final focus – a “crabbed waist” and has a longitudinally polarized LER beam • Beam currents and wallplug power are reduced from brute force extrapolations of the existing machines PEP-II and KEKB • Luminosity-related backgrounds and radiation levels in the forward/backward directions are high: require intensive study • Designing an appropriate detector is a tractable problem
Two nascent efforts • Both now employ versions of the “Italian scheme”: • Low emittance rings with large crossing angles >80ab-1 after6years 50ab-1 by ~2020 L~8x1035 10ab-1 ~ 2016 L~2x1035 3year shutdown for upgrade 2015? 2020?
What’s the killer “Shake the Box” app? • Is it the ability to discover lepton flavor-violating t decays and determine the chirality of the LFV coupling ? • Neutrino oscillations demonstrate the existence of neutral LFV couplings • Charged LFV are very small in the Standard Model, but measureable at a Super B factory • Is it the unique sensitivity to new CP phases beyond the CKM phase in B and Ddecay through studies of direct and indirect CP asymmetries? • Is it the sensitivity to the existence of a fourth quark generation ? • Is it the sensitivity to right-handed currents ? • Is it the sensitive tests of CPT invariance at the highest available q2 made possible by exploiting quantum coherence? • Is it the whole panoply of measurements and the pattern of effects uncovered that can serve as a “DNA chip” for New Physics found at LHC ?
Many SM extensions yield measurable effects in flavor physics Little Higgs w/MFV UV fix Generic Little Higgs Extra dim w/SM on brane Generic extra dim w SM in bulk SUSY GUTs SupersoftSUSY breakingDirac gauginos MSSMMFVlarge tan MSSMMFVlow tan Effective SUSY SM-like flavor physics Observable effects of New Physics after G. Hiller
Lepton Flavor Violation in t decays Super B Factory sensitivity directly confronts New Physics models BABAR SuperBsensitivity For 75 ab-1 We expect to see LFV events, not just improve limits
Lepton Flavor Violation in t decays • Impact of q13 in a SUSY seesaw model Antusch, Arganda, Herrero, Teixeira, JHEP 0611:090,2006
LFV 5s disc B 2 B MVF-NP extensions : meg vanishes as s130 tmgis independent of s13 CMSSM : meg vanishes at all SPS points
Lepton sector constraints in an SU(3)-flavored MSSM Lightest slepton mass Calibbi, Jones Perez, Masiero, Park, Porod & Vives arXiv 0907.4069v2
Beyond MFV LFV from CKM LFV from PMNS 107 B (tmg) now SO(10) MSSM SuperB Super B Factory M1/2 SUSY GUT now Super B Factory Allowed by Dms From Bs phase J.K.Parry, H.-H. Zhang hep-ph/0710.5443
LFV branching fraction ratios are discriminators Blanke, Buras, Duling, Recksiegel & Tarantino, arXiv:0906.545v1
Polarized t’s can probe the chiral structure of LFV in a model-independent manner A longitudinally polarized electron beam, producing polarized t’s,can determinate the chiral structure of lepton flavor-violating interactions Dassinger, Feldmann, Mannel, and TurczykJHEP 0710:039,2007; [See also Matsuzaki and SandaPhys.Rev.D77:073003,2008 ]
mixing is now well-established and large This raises the exciting possibility of searching for CP violation Super B Factory @ 75 ab-1 + +
CP violation in DC=2 mixing in an LHT model |q/p| from D→Kp, Kpp.. 75 ab-1 LHT model Little Higgs w T parity Bigi, Blanke, Buras & Recksiegel arXiv:0904.1545v3 [hep-ph]
CKM Fitter results as of Moriond 2009 The BABARand Belle CP asymmetry measurements together with improved precision in othermeasurements have produced a set of highly overconstrained tests, which grossomodo, are well-satisfied A closer look, however, reveals some issues
A variety of analyses have pinpointed tensions in the UT • These are all at the 2-3 s level, but occur in several places e.g., Lunghi and Soni analysis
Does the agreement of the overconstrained tests stand up to detailed scrutiny ? • There is actually some tension, and there are enough constraints to explore these issues • Caveats: • There may be Standard Model explanations for some effects • All issues are at the <3s level • Inclusive and exclusive Vub determinations are not in good agreement • There are also issues with inclusive/exclusive Vcb • The B(B→tn)conflict • The agreement of the fitted, i.e., SM-predicted value of sin 2bvs the directly measured value using tree decays and loop decays is not perfect • The Bs → ψϕphase • The Kp problem
The B(B→tn)conflict Effectively a measurement of fB Determines same constraint B(B→tn)also constrains Higgs doublet models G. Eigen
Is there a fourth quark generation ? • A fourth generation CKM-like mixing matrix has • 2 additional quark masses • 3 additional mixing angles • 2 additional CP-violating phases • A recent analysis by Bobrowski, Lenz, Reidl and Rohrwildshows that large regions of the new parameter spaces are still allowed • SuperB factories will be the primary tool to close this window, or, perhaps,to find significantly non-zero values ofthese fourth generation parameters q24 d14 q14 d13
New physics in Bd, Bsmixing ?? There isstill room for sizeablecontributions from New Physics Model-independentparametrization for New Physics in ΔF=2 transitions The preferred (SM+NP) ΔNP value iscurrently ~ 2σfrom SM for bothBd and Bssystems To clarify: Updated Tevatron result LHCb sin2bsmeasurement
W -H --g,0 b u,c,t s b u,c,t s b u,c,t s b d,s,b s CPV Probes of New Physics • In the Standard Model we expect the same value for “sin2 ” in modes, but different SUSY models can produce different asymmetries • Since the penguin modes have branching fractions one or two orders of magnitude less than tree modes, a great deal of luminosity is required to make these measurements to meaningful precision ~ ~ ~ ~ ~ ~ ~
Squark mass matrix (dsector) Super B Factories LHC
1500 1000 500 250 SPS-4 SPS-1 SPS-9 SPS-7 SPS-8 SPS-2 SPS-3 SPS-6 SPS-5 SUSY mass spectra for the 9 Snowmass points & slopes Ghodbane and Martyn
New Physics in CPV: sin2b from s Penguins… W- Many channels can show effects in the range DS~(0.01-0.04) s b f t s SuperB 75 ab-1 B0d s d d K0 ~ g ~ b s ~ b s X (*) theory limited
BgfK0 at 50/ab with present WA value J/yK0 fK0
Kinematic distributions in 1 0.5 FL 0 1 SM C7= – C7SM 0.5 AFB 0
Much more data is required for a definitive result • Can be pursued with exclusive or inclusive reconstruction • A measure of the relative merits is the precision in determination of the zero Exclusive Inclusive Theory error: 9% + O(L/mb) uncertainty Egede, Hurth, Matias, Ramon, Reece arxiv:0807.2589 Experimental error (SHLC): 2.1% Theory error: ~5% Huber, Hurth, Lunghi arxiv:0712.3009 Experimental error (Super B Factory): 4-6%
Conclusions • Shake the box physics will play a vital role in understanding new physics found at LHC • A full set of constraints requires studies of EDMs, (g-2)m, rare m and t decays, me conversion and rare K, D and B decays • High statistics (50-75 ab-1 ) data samples at e+e- Super B Factories provide both • discovery potential • charged lepton flavor violation • CPV in mixing, and • A DNA chip to discriminate between model of New Physics • The achievable levels of sensitivity in rare b, c and decays provide substantial coverage in the parameter space • The Super B Factory programs, of course, overlap with the programs of LHC flavor experiments such as LHCb, but the e+e- environment makes possible a substantial number of unique and important physics measurements in areas sensitive to New Physics
B Physics: (4S) Charm mixing and CPV Charm FCNC Bs Physics: (5S) Physics