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					    (Heavy) Flavor Physics
                      at
B-Factories, HERA, Tevatron, LHC
       (collider experiments)
                   Y,Sakai KEK

              XXI Rencontres de Blois
          "Windows on the Universe"
 2009.06.25                             1
          Rich Heavy Flavor Physics
      SM/CKM                                          New Physics
                                 Hadronic     B0
                                 Penguins
                        Mixing        B        CP violation
                   Bs         Semi-leptonic           Tree
 Lifetime                       decays          D0    decays
       Radiative         Bc                       Pure-leptonic
       Penguins
                          Electroweak       Ds       decays       D
Lb       LFV              Penguins                New
                    t                         resonances    Production
G.H.Monchenault
K.Lipka, H.Evans

        Try to review most important aspects (w/ my view)
                                                                     2
                Flavor Physics
Transitions between “Flavors”
                           Started from “strange” particles

       quark sector            Standard Model
                                 Weak Interaction
   u        c         t      Kobayashi-Maskawa
                             predicted essential nature
                             of SM (1973)
   d        s         b
                               • 3 Generations
                               • CP Violation
                      1964: CPV discovered in K0 decay
                      Only 3 quarks (u,d,s) were known   3
2008 Physics Nobel Prize
          35 years after prediction !

                     1974: c quark
                     1977: b quark
                     1995: t quark

                2001: CPV in B-meson
                ~2008: many supporting
                       new results

                  Experimental proof


                                        4
                 CP Violation
 “Window on Universe” (from Particle physics)
  Universe: almost “matter” only (no anti-matter)
    Big-Bang  N(particles) = N(anti-particles)

                   Sakhalov’s 3 conditions (1967):
                    1. baryon number violation
                    2. CP violation
                    3. existence of non-equiblium


CPV is a key for Existence of Universe & us !
                         Andrei Sakharov (1921-1989)
                                                       5
        Kobayashi-Maskawa: CPV
CPV: due to a complex phase in the quark mixing matrix
CKM matrix                                        W-
     d '  VudVusVub  d                     dj
                                                    Vkj
                                                                 uk
     s '   VcdVcsVcb  s                 Weak Interaction
     b'  V V V  b                        (charged current)
       td ts tb  
 Wolfenstein representation                    4 parameters (,, , A)
     / 2                A (   i ) 
                                             + O(4)
                    / 2
                         
                                  A  2
                                             
  A (1    i )  A2                    = sinqc )
                                                   q : Cabibbo angle
                                                      c
                                                                      6
                “Unitarity Triangle”
CKM matrix: unitary
 V†V   = 1 (S VijV*ik = djk )      A(   i )
                                   3                       A(1    i )
                                                           3


  j=1(d), k=3(b)                       V V
                                        V V
                                        ud ub
                                             *
                                          ub ud
                                                      2(a)        
                                                                 VtbVVtb *
                                                                 Vtd td
                           
V ubV u d V cbV c d V tbV td  0           3 (g)            (b)
                                                                        1
                                                          
                                                       Vcb Vcd 3 A
                                                      Vcd Vcb*
                                  
                                  _
 Normalize by
                                              (,)
                                              __
     |V*cbVcd | (=A3)
                                       |Rb|             |Rt|
           =     (12/2)                         (a)
           _

            =  (12/2)
           _                               (g)          (b)       (1,0)
                                                                              
                                                                              _
                                                      1
                                                                              7
      Experimental measurements
Transitions between “Flavors”                                          Varieties of
                                                                       Measurements
                                                                       in wide ranges
Measure CKM matrix elements
                                                            Fundamental quantities
    “Unitarity Triangle”                                    (same origin as masses
                                                             from Yukawa int. w/ Higgs)

        CP Violation  phase(angles)
         • b-quark (B physics)                                 *
           plays important role
                                                          Vud Vub
                                                                    2 a)         *
                                                                             Vtd Vtb

New Physics beyond SM                                          3 g)             1b)
* There are many other important Flavor physics results                Vcd Vcb*
                                                                                          8
        e+e Asymmetric B-factories
               Mt. Tsukuba                           SLAC   3.1 x 9GeV
                    3.5 x 8 GeV              PEP-II
 KEKB
               Belle



~1 km in diameter                             BaBar
                                                            stop Apr-2008

                           World Highest Lum.
                           L = 2.1/1.2 x 1034 cm-2s-1
                                         _
                           (775+465M BB @Y(4S))
                             Clean environment
                           Also, t/charm factories                    9
            Hadron Colliders
Tevatron (Fermilab)    LHC (CERN)
 _
pp @1.96 TeV             pp @14 TeV




                              _
                      Large sbb, small S/N
                      Selective trigger
                      Bs, Bc, Lb
                                             10
           ep collider: HERA
27.5(e) x 920(p) GeV                    Mainly on
                                        production &
                                        fragmentation
                                        mechanism
                                         n source in CR
                                        (window of universe)
                                                             _
                                                       F2   bb
                       stop June-2007




                                p

                                                        11
                       CPV in B0 decays
                                    _
                   A                                    A
     B0                    fcp                                    fcp     Sanda
                                      =        B0
                                                                          Bigi
mixing        B0                                       B0
                       A                                         Decay: A Carter
     _     V*td                  _                                      _
_                                                   _    V*cb           c
     d             _
                   t
                                 b                  b                       J/y
B0        w                w          B0     B0              w          c
                                                                        _
     b             t             d                  d                   s
                   V*td                                                 d   K0
             Initial: B0
                                           Interference
          B0 _
                 Oscillation                Direct decay                Weak
             B0                             Mixing + Decay              Phase
                   frequency: Dmd                                       difference
                           (BH, BL)
                                                  Decay-time dependent CPV
                                                                                  12
                           CPV in B0 decays
                                        _
                       A                               A
           B0                  fcp                           fcp     Sanda
                                     =       B0
                                                                     Bigi
  mixing          B0                                  B0
                           A                                Decay: A Carter


                mixing

Vud Vub*
           2a)       Vtd Vtb *         f sin21 sin(Dmd Dt)
                                                                      _
                                     Prob.
                                                  B0                  B0
       3g)               1b)
                Vcd Vcb*
                                     ACP
                           Decay                                   sin21
                  f : CP eigenvalue)
                                                   Dt (decay time)[ps]      13
                CPV meas. at B-factories
                      Inclusive info.     Flavor-tag
                      (lepton, K etc.)                        Reconstruction
                                          (B0 or B0 ?)
                                                 eeff ~30%        J/y
              e
        e                                                                   fCP
                            t=0             Dz
                   Vertexing                                            KS
                                         sDt~140ps

                B0                                    B0         fit
Prob.




                                                                        Extract
             B0-tag                                  B0-tag
                                                                        CPV

                      Dt  Dz/cbg                    bg=0.425 (KEKB)
                                                        0.56 (PEP-II)
                                                                               14
            First Observation: CPV in B
                             _
            1137             B0 tag          2001
            events           B0 tag




                                                                Events
                                         (     )
Asymmetry




                                         J/y K*0                              _




                                                    Asymmetry
                                                                         32M BB

                        31M BB

                 [PRL 87,091802(2001)]                                    [PRL 87,091801(2001)]
sin2= 0.99  0.14 0.06                                            0.59  0.14  0.05
                                                                                                  15
        Now: Precise measurement
                                                       _         _
           535M BB     14000                     465M BB       (cc)K(*)0
                       signals
     BJ/yKs             B0 tag
                         _                                     12000
                                                               signals
                         B0 tag
                                   CP-even



     BJ/yKL

                                    CP-odd



+y(2S)KS            Av. 0.670  0.023: 3.4% error !
sin2= 0.650  0.029  0.018           0.687  0.028  0.012
    [PRL 98,031802(07)+PRD77 091103(08)]     [PRD 79,072009(2009)]    16
             Determination of UT
       Complete Test of KM(CPV) and SM
                    B pp, p,                     |Vtd /Vts | by Bs-mixing
                                                                        ( D m s)
b u ln                           Vtd Vtb *
              Vud Vub*    2                     B0-mixing (Dmd)
B p/ l n                   (a)
                                                 B g
                     3(g)                (b)   1
  B      DCPK
                               Vcd Vcb*                     -
                                                     B0  (cc)K(*)0
  B0   D(*)+p
                         b  c l n                  B0  D*+D(*)-(K)
                         B  D(*)l n
                                                 Over constraint !
    B measurements can provide all needed !
                                                                              17
                               Bs-Mixing
         _   V*ts              _
_        s          _          b            |Vtd|         Dmd
                    t
Bs           w           w         Bs       |Vts|
                                                  = c’x
                                                          Dms
         b          t          s
                        V*ts
     _                                  _
Bs-Bs : expected to mix like B0-B0, but much high frequency
Precise Dms  precise |Vtd|
                                                           Difficult
       (Dmd: precisely measured, |Vts|= 2)                to measure
  Dmd = (0.507  0.005) ps-1
          (~1% error) [PDG]

Tevatron experiments
  finally measured (2006)
                                                                        18
                   Bs-Mixing : results
                         _
• Flavor-Tagged Bs/Bs decay time distribution ~Oscillation
       reconstruct Bs  Dsp(pp), Dsl n
• Amplitude analysis (vs freq. = Dms) [~ spectrum analyzer ]



   1.0 fb-1                              2.4 fb-1


     5.4s significance                     2.9s significance

Dms = (17.77  0.10  0.07) ps-1        (18.53  0.93  0.30) ps-1
 [PRL 97,242003]    (~0.7% error !)

    |Vtd /Vts | = 0.209  0.001  0.006             1st step for Bs CPV
                                 (LQCD error)                         19
        Summary of CKM/UT
All measurements agree to form UT !




KM-phase = source for CPV: Established !
     Still room for New Physics (for ~10% effect)
                                                    20
 In spite of Great Success of SM, there must be
       New Physics beyond SM at High Energy scale
       (SM is valid effective theory at current E-scale)

Observed CPV in SM is not enough
to explain matter dominance of Universe
                                         [>O(1010)] !

New Source of CPV should exist                    (beyond SM)

One of Next important goals of Flavor Physics
                           Energy Frontier
Note) NP effects appear in Flavor Physics in various way !
                                                             21
                              -
     New Source of CPV: b  sqq
     b     t        s ,’.. b       X        s ,’..
_                   s
B0                       +                    s
                    s                         s K
     d              d KS     d                d S
         Vts Vtb*

     SM: bs Penguin         + New Physics
               -
     phase = (cc) K0           with New Phase
                              Sbs  Sbc , ADCP can  0
      _
“b  ccs: sin21” (SM reference)      deviation
                                                     22
    Summary of New CPV search

B0 J/yK0
Reference point of SM

No clear deviation seen
in all modes (1~2s)

New CPV effect can be
seen with much larger
data

    Super B-factory
                                23
           New CPV in Bs  J/y 
 Bs version of B0 J/yK0 CPV: sin2bs~0 in SM
   Large CPV(sin2bs)  clear New Physics CPV
   DGs = GL  GH
         (cf: DGd ~ 0)



   ~2s hint of NP ?
  (combined 2.8 fb-1 soon)
More data at
 Tevatron (8-10 fb-1)

  LHC (LHCb,
        ATLAS,CMS)
                                               24
        NP searches in Flavor Physics
                                       New Exotic Resonances
 AFB in   BgK*ll                                                      Evidence for Bgtn

                                                                          Signal



                              Events
                                           X(3872)                          3.8s
                                                     Z(4430)

             Belle, 2008




 D0-D0 mixing
Observed in 2007                                               BgD*tn      Bs/dgmm
                             Bgdg transition



    .
x=(1.0 0.25)%
y=(0.76 0.17)%


                           Need much more data for NP !                   and more…    25
            Super B-factories
SuperKEKB (Japan)            SuperB (Italy)
                  Belle II




Belle II
                   Both aim L ~1036 /cm2s or more
                   Integrated Lum. >50 ab-1
   Somewhat different approach: scheme/timeline
                                                26
   Prospects : Super B-factory
CKM UT triangle
        Now




    NP effect              New CP phase




      50ab-1
                      50ab-1   Theory errors
                                          27
          LHC(b) & Super B-factory
                                H   Even current constraints
                                      are competitive
                       Bs




                     Common
           50ab-1

                                                         ATLAS


                    No IP
                    g,n

S.Stone             Error


     Complementary each other                             28
                 Conclusion
 Flavor physics plays essential role in SM
   Successful theory of current energy scale
   Many tests proved by B-factories & Tevatron

 CPV 2008 Novel prize to Kobayashi-Maskawa
 New source of CPV in higher energy scale
    to explain matter dominance of universe
 Flavor Physics & CPV
        = “Windows on the Universe”
            LHCb & Super B-factory
                                                 29
           Rich Heavy Flavor Physics
       SM/CKM                                         New Physics
                                 Hadronic     B0
                                 Penguins
                        Mixing        B        CP violation
                   Bs         Semi-leptonic           Tree
 Lifetime                       decays          D0    decays
       Radiative         Bc                       Pure-leptonic
       Penguins
                          Electroweak       Ds       decays       D
 Lb       LFV             Penguins                New
                    t                         resonances    Production

G.H.Monchenault
K.Lipka, H.Evans
                                                                     30
        Belle and BaBar Detectors
                    m/KL detector (RPC+Fe)
                    CsI(Tl) EM calorimeter
                      SC solenoid (1.5T)




TOF counter &
Aerogel Cherenkov      Si Vertex detector          DIRC
                      Drift Chamber (small cell)

                                                          31
Peak Luminosity
                  2.1x1034
                  1.2x1034




                             32
Integrated Luminosity
                    KEKB + PEP-II


                    ~945 fb-1 (6/19)
                     KEKB
                     for Belle


                    PEP-II
                    for BaBar
                        ~553 fb-1


                                 33
         Direct CP Violation : B  Kp
                              _
                         Vus   s                          W
   “Tree”                         +                 Vtb       V s “Penguin”
                    W          uK              b
                                                                ts
               b                                          t   g      K+
               0   Vub         u             0                     u
          B                                B d
               d
                                   p                                  u p-
           d                   d               d                       d
                                                         _ _
                                                       N(B f )  N(B f )
                                                 ACP =   _ _
                                                       N(B f )  N(B f )
                                                          Mixing is not involved
                                          Predicted by KM: observed in 2004
                                        Predicted by KM : observed in 2004
                                        Now (Belle + BaBar)
                                          Acp(Kp) = 0.098  0.0 @ 8.1s
                                                              0.0
                                          Acp(Kp0) = 0.050 ± 0.05 @2.0s
                                           DAKp = Acp(Kp-)  Acp(Kp0) Hint of
Nature 452, 332 (2008)                     = 0.47± 0.08 @ 5.3s       NP ?
         535M BB                                                                   34
                                      2 Summary
            mixing
Vud Vub*
           2a)     Vtd Vtb *

       3g)              1b)
               Vcd Vcb*

                          _
               Vud         d
                                 +
           W               u p/
  b
B0         Vub             u
 d
                               p/-
  d                        d

 Time-dep. CPV

                          2/a = [89.0 ± 4.3] (4.8% precision)
                                                              35
               3 Summary




                     3/g = [70   +27
                                  9   ]
interference
                                             36
       |Vcb | & |Vub | measurements
Semileptonic B deacys: reasonably good theoretical understanding
                      exclusive final states
 two ways             inclusive final states
                      l-                                      l-
   Vcb,Vub                                Vcb,Vub
                       nl
                                                              nl
               W-                                      W-

   b                c(u)                  b                 c(u)
PDG2008
                                               SEVERAL THEORETICAL
|Vcb| = (42.1 ± 1.1)   x10
                           (2.6%)              APPROACHES TO HANDLE
|Vub| = (3.93 ± 0.6 ) x10 (9%)              HADRONIC EFFECTS

                                                                    37
                                     B0s/d Mixing
  Mass eigenstates  Flavor eigenstates
                                      0
    BL      p B0  q B                     (L : Light)             q        *        *
                                                                            M12-(i/2)G12
                                                                    p=      M12-(i/2)G12
                                       0
    BH      pB  q B0
                                            (H : Heavy)
                                                                     H = MiG/2
  x = (mH – mL)/ G, y = (GL – GH )/ 2G                                Mass matrix Hamiltonian



Time evolution
                                                                                              
   B 0 0)  B 0 t )  e          cosh ( y  ix )Gt / 2) B  sinh ( y  ix )Gt / 2) B
                            im t tG / 2                     0 iq                        0
                                 e                                                             
                                                                p                             
                     im t tG / 2                                                            
   B 0)  B t )  e e              cosh ( y  ix )Gt / 2) B  sinh ( y  ix )Gt / 2) B 0
    0       0                                                 0  ip
                                                                                              
                                                                 q                            


                                                                                                   38
                                  Bq Mixing
                                                                          
                 Vtd t     Vtb                                  Vts t     Vtb
        d                           b                   s                            b
B   0
    d           W           W           B   0
                                            d   B   0
                                                    s          W           W             B    0
                                                                                              s

        b                           d                   b                            s
                                                                  
                 Vtb t Vtd                                      Vtb t Vts

    Dmd = Cd BBd fBd2 |Vtb* Vtd |2                  Dms = Cs BBs fBs2 |Vtb* Vts |2

        BBd fBd=223  35 MeV                                BBs fBs             0.047
                                                x                      .   0.05
            (~15% error)         Lattice QCD                BBd fBd
                                                                         (< 4% error)
                                 (unquenched)
                                                              = c’x Dmd
        |Vtd| ~15% error                                |Vtd|
                                                        |Vts|        Dms
        ( |Vtd| = 1, Dmd < 1% error )                          A2 (~2% error)
                                                                                         39
                SM CPV: too small
nB          nB
ng  0      ng  (5.10..2 ) 1010
                     
                       03
                                           KM ~ 1020
                      WMAP
                                          Too Small in SM
  Why? Jarlskog Invariant in SM           (need 3 generation in KM)




     Normalize by T ~ 100 GeV
                                             masses too small !

                 5
                                  in SM
         A ~ 310     is common (unique) area of triangle
                    CPV Phase
                                                              [W.S.Hou]
                                                                      40

				
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