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Achille Stocchi (LAL Orsay/IN2P3-CNRS Universit é Paris-Sud)

Introduction to Heavy Flavour Physics (..more on CKM and CP violation). Achille Stocchi (LAL Orsay/IN2P3-CNRS Universit é Paris-Sud). in 25 minutes. Short introduction. Main motivations. Selection of new measurements. The present situation. How and why.. to go on…. Short Introduction.

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Achille Stocchi (LAL Orsay/IN2P3-CNRS Universit é Paris-Sud)

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  1. Introduction to Heavy Flavour Physics (..more on CKM and CP violation) Achille Stocchi (LAL Orsay/IN2P3-CNRS Université Paris-Sud) in 25 minutes Short introduction. Main motivations Selection of new measurements The present situation. How and why.. to go on…

  2. Short Introduction. Main Motivations

  3. Flavour Physics in the Standard Model (SM) in the quark sector: 10 free parameters ~ half of the Standard Model 6 quarks masses 4 CKM parameters Wolfenstein parametrization : l ,A, r, h h responsible of CP violation in SM In the Standard Model, charged weak interactions among quarks are codified in a 3 X 3 unitarity matrix : the CKM Matrix. The existence of this matrix conveys the fact that the quarks which participate to weak processes are a linear combination of mass eigenstates The fermion sector is poorly constrained by SM + Higgs Mechanism mass hierarchy and CKM parameters

  4. The Unitarity Triangle: radiative decays Xsg,Xdg, Xsll B pp, rp, rr... theo. clean ? B DK +other charmonium Charm Physics (Dalitz) +from Penguins

  5. sin(b+g) How measurements constraint UT parameters a g the angles.. sin(2b) Dms Dmd Vub/Vcb the sides... CP asymmetries in charmless BK*(r)g Btn … Rare decays... sensitive to NP

  6. From Childhood In ~2000 the first fundamental test of agreement between direct and indirect sin2b To precision era WE HAVE TO GO ON…

  7. Before starting… We observe hadrons and not quarks ! theory gives us the link from quarks to hadrons OPE /HQET/Lattice QCD …. Need to be tested ! To access the parameters of the Standard Model we need to control the effects induced by strong interactions Many measurements ( with different weights ) are essential Decay properties and production characteristics Lifetimes beauty and charm physics are equally important Branching ratios Form factors Masses (spectroscopy) Kinematic distributions

  8. Selection of new measurements(*) (*) some (partial) selection of important measurements which will be discussed at this conference. Touch and go. A sort of “fil rouge” There are many others, apologies for not treating them. I put some results on the backup material

  9. Direct also with B+ A1 B0 fCP direct Interference mixing-decay A2 A1 M12 mixing G12 A2 B0 Angles are accessible through CP violating measurements g a,b Analogy: “Double-Slit” Experiments with Matter and Antimatter source In the B experiment, we must choose final states that both a B0 and a B0 can decay into. We perform the B experiment twice(starting from B0 and from B0). We then compare the results. In the double-slit experiment, there are two paths to the same point on the screen.

  10. The precision on sin2b is still improving.. direct indirect b c ~only one amplitude J/y c B0d s K0 d d theoretically clean at ~0.01 To improved with data! Dt(ps) sin2b gives the best constraint on r-h plane Dt(ps) sin(2b)

  11. W- s b f t s B0d s K0 d d sin2b from “s Penguins”…a lot of progress.. ~ g ~ ~ s b s b New Physics contribution (2-3 families) Disagreement between sin2b from bccs and bqqs still there and intriguing.. “CP violation observed in h’Ks”

  12. Some discrepencies observed between Vub and sin2b sin2b=0.675±0.026 From direct measurement We should keep an eyes on these kinds of disagreements. Could be NP sin2b =0.764± 0.039 from indirect determination (all included by sin2b)

  13. B p l n Progress on Vub.. B Xu l n Exclusive : we start to have quite precise analysis of Br vs q2 Inclusive : improving analyses and improving the control of the theory vs cuts Br ~ |Vub|2 in a limited space phase region… untagged analysis is the most precise Using Babar El, (Xsg) Important that we measure at high q2 where Lattice QCD calculates better. El Confirming disagreement…

  14. SM predictions of Dms LEP/SLD 1999 CDF 2006 LEP/SLD 2002 2 Dms Dmd f B D A Milestone : the meaurement of the Bs oscillations after a long saga.. m B B 2 2 2 d µ l - r + h (( 1 ) ) d d D 2 m f B s B B s s 1/x2 CDF only : signal at 5s -0.21 Strong impact on NP on Bs sector. See later Limiting factor : precision on the hadronic parameter x

  15. A second milestone : the measurement of the leptonic decay Btn First leptonic decay seen on B meson SM expectation BR(B → τ ν) = (0.85 ± 0.13)10-4 Exp. likelkihood BABAR+BELLE BR(B → τ ν) = (1.31 ± 0.48)10-4 fB = 237 ± 37 GeV from exp+UTfitfB = 189 ± 27 GeV Lattice QCD

  16. Use D0 from D* to tag the flavour of D0 D*+ D0 p+ Wrong sign : WS mixing D0 doubly Cabibbo suppressed(DCS) Cabibbo favoured(CF) K-p+ D0 • strong phase CF/DCS ampl. rotation (x,y)(x’,y’) mixing no mixing 3.9s evidence no mixing Mixing in D0 -D0 system Observed !! BaBar Submitted to PRL (hep-ex/0703020) DCS decays Interference Oscillations (1 ± cosDm t) ~ x2/2 idem for DG ~ y2/2

  17. Belle : CP eingenstate lifetimes Method using Dalitz ex : D0 K0Sp - p + RS and WS occupy the same Dalitz plot Measurement of strong phase d Constraint on x,y2 ( also sensitive to sign of x) K-K+ (or p-p+) pure CP D10 K -p+ 50% D10 + D20 Constraint on y Compare assuming d=0: (x'=x, y'=y) Best fit Belle life. (1s) 2.4s Belle Dalitz ALL is very exciting. D mixing is Now observed, we need more Measurements with different techniques to get x and y parameters. Within 2s, less if 0 Two talks tomorrow +theory talk….

  18. Testing lattice QCD on charm sector : form factors Semileptonic D decays. example DK l n D fDs, FD from CLEO-C Precise measurement, test of the QCD calculation on charm sector  Could be used on B sector : x, Vub..

  19. The present situation How and Why.. to go on… I’ll discuss the present knowledge of the CKM matrix and CP violation in the SM and beyond and at the same time try to see what do we need ( theory and next facilities) to effectively look for NP I’ll use some simulation done for a possible SuperB facility with 75ab-1

  20. SM Fit Global Fit Dmd,Dms,Vub,Vcb,ek + cos2b + b + a + g + 2b+g r = 0.163 ± 0.028 h = 0.344 ± 0.016 We are beyond the era of « alternatives» to the CKM picture. NP should appear as «corrections» to the CKM picture

  21. The problem of particle physics today is : where is the NP scale L ~ 0.5, 1…1016 TeV The quantum stabilization of the Electroweak Scale suggest that L ~ 1 TeV LHC will search on this range What happens if the NP scale is at 2-3..10 TeV …naturalness is not at loss yet… Flavour Physics explore also this range We want to perform flavour measurements such that : - if NP particles are discovered at LHC we able study the flavour structure of the NP - we can explore NP scale beyond the LHC reach

  22. Fit in a NP model independent approach DF=2 Parametrizing NP physics in DF=2 processes No new physics C=1 j=0 Tree processes 5 new free parameters Cs,js Bs mixing Cd,jd Bd mixing CeK K mixing 13 family Constraints 23 family Today : fit possible with 10 contraints and 7 free parameters (r, h, Cd,jd ,Cs,js, CeK) 12 familiy

  23. if SuperB Model Indep. Analysis in DB=2 C = ± 0.031 f = (± 0.5)o C = 1.24 ± 0.43 f = (-3.0 ± 2.0)o Factor 3-4 gain on NP scale NP scale ~200GeV with MFV couplings In some more favourable case MH (TeV) tanb NP~700 GeV Precision will be enough to have 5s discrepancy with today central values Similar plots in Bs sector where the impact of LHCb is crucial

  24. Example on how precise measurements could allow to explore NP scale beyond the TeV scale ~ g MSSM ~ ~ New Physics contribution (2-3 families) s b s b 1 10-1 10-2 In the red regions the d are measured with a significance >3s away from zero 1 10 With the today precision we do not have 3s exclusion for any set of parameters

  25. Some final considerations Flavour Physics is now in mature age. Many measurements have been performed and many new we will discuss at this conference. Some stringent test of SM has been done (sin2b, Dms…) It is a very active an lively field with many new results : highlight D0 mixing !! Our goal is to find NP or to measure the parameters of NP. Quite a lot of work has been done More we need to to.. For it we need : Precise measurements (at 1%) Precise theory (Lattice calcs at 1%)

  26. ..but I’m sure it will be a dream !! Could be a nightmare…. Adjusting the central values so that they are all compatible Keeping the central values as measured today We need to go on in measuring precisely many different quantites ACP(BXg) AFB(BXll) CPV in CF and DCS D decays Br(tmg) …… CKM angles a,b,g Br(Btn) and B Dln |Vub|,|Vcb| radiative decays : Br(Brg, K*g) many other measurements…

  27. BACKUP MATERIAL

  28. Bccs : 1 /b K : CPV in K decays bcℓ and buℓ Bd and Bs mixing B// : 2/ BDK : 3/ An example on how to fit the UT parameters and fit new physics

  29. B0 D0 h0 Together with J/y Kp , D*D*K Help in distinguishing between the two b solution from sin2b measurement

  30. Many novelties on the measurement of the angle a Not only “Tree” diagrams contribute to final states but also “Penguins”. Isospin analysis necessary to extract a pp modes rr modes Important measurement because it gives the contributions of Penguins diagram consistent with no CP violation aeff~90o (0/180)o New results also on rp(time dep. Dalitz analysis)

  31. The angle g : still quite a lot of work to do… Most precise measurement come from Dalitz analysis with D0Kspp critical the value of rb Babar more precise than Belle on x,y but found a smaller rB larger error on g New D0 decay explored BaBar

  32. Precision measurements of |Vcb| Essential point is to control /“measure” the effects of strong interaction Inclusive Vcb still progress… Same for exclusive.. BD*ln (Babar) Events/0.5 here we extract : limiting factor F(1) BaBar/CLEO/CDF/DELPHI Kinetic scheme Study on charm sector help in the understanding of strong dynamics

  33. Radiative B decays : moving beyond BK*g - many measurement on Bsg - measurements of Br on Bdg - measurement of ACP on exclusive and inclusive modes

  34. SM Fit Are there evidence of disagreement in the actual fit ? agreement between the predicted values and the measurements at better than : 1s 3s 5s 2s 4s 6s No disagreement for g et Dms

  35. t o d a y L H C b

  36. NP scale at 350 GeV Due to the actual disagreement betweenVub and sin2b we see a slight hint of new physics Re (dd13)LLvs Im (dd13)LL superB if disagreement disapper. SM Re (dd13)LLvs Im (dd13)LL with present disagreement NP at high significance ! Constraint from Dmd Constraint from sin2bcos2b Constraint from sin2bAll constraints

  37. MSSM ~ g With the today precision we do not have 3s exclusion New Physics contribution (2-3 families) ~ ~ s b s b 1 10-1 10-2 1 10-1 In the red regions the d are measured with a significance >3s away from zero 1 10 1 10 In this case the main constraints are bsg ACP(bsg) Today we would have magenta contour covering all the space

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