Measurements of Measurements of 11// and and 22//
Masashi Hazumi (KEK)Masashi Hazumi (KEK)
July 31, 2006XXXIII International Conference on High Energy Physics (ICHEP’06)
Many thanks to many people, in particular to: T. Aushev, T. Browder, P. Chang, R. Faccini, K. George, T. Gershon, K. Hara, H. Ishino, A. Lazzaro, S. Olsen, Y. Sakai, O. Tajima and K. Trabelsi
2
New ResultsNew Results fromfrom BaBarBaBar andand Belle Bellefor Stringent Tests of the for Stringent Tests of the
Kobayashi-Maskawa Model of Kobayashi-Maskawa Model of CPCP Violation Violation
3
Main New Results Covered in This TalkMain New Results Covered in This Talk(all results are preliminary)(all results are preliminary)
• 11 with tree diagram (b with tree diagram (b ccsccs))• BaBar: sin2BaBar: sin2 in in BB00 J/ J/(2S)(2S)KKSS, , ccKKSS, , c1c1KKSS, J/, J/
• Belle: sin2Belle: sin211 in in BB00 J/ J/
• 11 with penguin diagram ( with penguin diagram (bb sqqsqq))• BaBar: BaBar: BB00 KK++KKKK00, , ’’KK00, , KKSSKKSSKKSS, , KKSS, , KKSS, , 00KKSS
• Belle: Belle: BB00 ’’KK00 , ,00KKSS
• Belle: Belle: BB00 KK00, , KK++KKKKSS , , KKSSKKSSKKSS , , f f 00KKSS, , KKSS
• 2 2
• BaBar: BaBar: , , , , • Belle: Belle: • Belle: Belle:
K.HaraK.Hara
K.GeorgeK.George
A. LazzaroA. Lazzaro
O. TajimaO. Tajima
This talkThis talk
This talkThis talk
H. IshinoH. Ishino
S. TelnovS. Telnov
4
• Some other new results and recently published results also mentioned but very briefly.
• /3-related R.Kowalewski (next speaker)
• My apologies if your favorites are not included
RemarksRemarks
5
2525thth Anniversary of Anniversary of Time-dependent Time-dependent CPCP Violation (t Violation (tCPCPV)V)
6
Tony, are you nuts?
Look at this.
We need millions of B
and use them to
search for mixing and CP violation
This took us six months!
Tributefrom S. Olsen
5 B mesons
7
PEP-II at SLAC
KEKB at KEK
Belle
BaBar
9GeV (e) 3.1GeV (e+)peak luminosity:
1.121034cm2s1
Two Asymmetric-energy Two Asymmetric-energy BB Factories Factories
8GeV (e) 3.5GeV (e+) peak luminosity:
1.651034cm2s1
world record
11 nations, 80 institutes, 623 persons
13 countries, 57 institutes, ~400 collaborators
8
Integrated LuminosityIntegrated Luminosity
PEP-IIfor BaBar
As of July 24, 2006
KEKBfor Belle
KEKB + PEP-II
9
• Far beyond the design luminosities of both proposals• Triumph in accelerator science
reached on July 13, 2006
~ 1 Billion BB pairs
10
MotivationMotivationQ. What is the main source of CP violation ?
A. Kobayashi-Maskawa phase IS the dominant source !
Two promising approaches1) Overconstrain the unitarity triangle: precise measurements of and needed2) Compare sin2 in tree diagram and penguin diagram (e.g. b s)
sin2 history(1998-2005)
Q. Are there deviations from the CKM picture ? (e.g. new CP-violating phases)
Paradigm shift !
11
11
12
Time-dependent Time-dependent CPCP violation (t violation (tCPCPV)V)“double-slit experiment” with particles and antiparticles“double-slit experiment” with particles and antiparticles
b c
d
csd
J/KS
b
d cJ/KS
bcsddt
t
+
Quantum interference between two diagrams
tree diagram box diagram + tree diagramVtd
Vtd
You need to “wait” (i.e. t0) to have the box diagram contribution.
You need to “wait” (i.e. t0) to have the box diagram contribution.
13
ttCPCPV in BV in B00 decays decays
(A = C a la BaBar)
Mixing-induced CPVMixing-induced CPV Direct CPVDirect CPV
e.g. for J/ KsS = CPsin21 = +sin21 A = 0to a good approximation(CP : CP eigenvalue)
e.g. for J/ KsS = CPsin21 = +sin21 A = 0to a good approximation(CP : CP eigenvalue)
14
)cossin(141
,1 tmAtmSetqPt
)21( w
R
R : detector resolutionw : wrong tag fraction (misidentification of flavor) (1-2w) quality of flavor tagging They are well determined by using control sample D*l D(*) etc…
S = 0.65A = 0.00 B0 tag
_B0 tag
B0 tag_B0 tag
-CPsin21
Mixing of D*lGood tag region(O
F-SF
)/(O
F+SF
)
t| (ps)
15
11 with trees with trees
- Results -- Results -
16
BB00 J/ J/ K K00 : 535 M BB pairs : 535 M BB pairs
2*/
2*KsJbeambc PEM
B0 J/ KS B0 J/ KL
Nsig = 7482Purity 97 %
CP odd
Nsig = 6512Purity 59 %
CP even
pKL information is poor lower purity
Belle preliminary
0 0
__
BELLE-CONF-0647BELLE-CONF-0647
O. TajimaO. Tajima
17
B0 J/ KS
B0 tag_B
0 tag
0 B0 J/ KL
B0 tag_B0 tag
0
Asym. = -CPsin21sinmt
sin21= +0.643 ±0.038 A = - 0.001 ±0.028
sin21= +0.641 ±0.057 A = +0.045 ±0.033
stat error stat error
BELLE-CONF-0647BELLE-CONF-0647
O. TajimaO. Tajimabackgroundsubtracted
18
B0 J/ KS
B0 tag_B
0 tag
0 B0 J/ KL
B0 tag_B0 tag
0
B0 tag_B
0 tag
BB00 J/ J/ K K00 : combined result : combined result
Asym. = -CPsin21sinmt
sin21= +0.643 ±0.038 A = - 0.001 ±0.028
sin21= +0.641 ±0.057 A = +0.045 ±0.033
stat error stat error
BELLE-CONF-0647BELLE-CONF-0647
O. TajimaO. Tajima
19
BB00 J/ J/ K K00 : combined result : combined result
sin21= 0.642 ±0.031 (stat) ±0.017 (syst) A = 0.018 ±0.021 (stat) ±0.014 (syst)
previous measurementsin2= 0.652 0.044
(388 M BB pairs)
B0 tag_B
0 tag
535 M BB pairs_ _
Belle preliminary BELLE-CONF-0647BELLE-CONF-0647
O. TajimaO. Tajima
20
K.GeorgeK.George
A = 0.07 0.028 0.018
BaBar2006: sin2BaBar2006: sin2 in b in b ccs ccs
BB00 J/ J/(2S)(2S)KKSS, , ccKKSS, , c1c1KKSS, , J/J/
21
2006: BaBar + Belle2006: BaBar + Belle
Consistency with Vub, 3/ R. Kowalewski (next speaker)
22
(not sin2(not sin2) measurements) measurements
B0D*+D*KsTime-dependent Dalitz analysis (T.Browder, A. Datta et al. 2000) cos2 > 0(94%CL, model-dependent)
B0Dh0 (h0 = 0 etc.)Time-dependent Dalitz analysis cos2 > 0Belle: 98.3%CL(hep-ex/0605023, accepted by PRL)BaBar 87% CL (BABAR-CONF06/017)
K.GeorgeK.George
23
11 with penguins with penguins
24
3 theoretically-clean modesKs, ’Ks, 3Ks
25
Results for Results for 3 theoretically-clean modes3 theoretically-clean modes
KK00, , ''KK00, KsKsKs, KsKsKs
26
Belle 2006: Belle 2006: BB00 KK0 0 signalsignal
B0 mass
B0 momentum
_535M BB
(bkg subtracted)
KK, KS
KK, KS
KSKL, KS
114 17 KL signal
114 17 KL signal
307 21 KS signal
307 21 KS signal
Three modes
New !
BELLE-CONF-0647BELLE-CONF-0647
27
Belle 2006: tBelle 2006: tCPCPV in V in BB00 KK00
“sin21” = 0.50 0.21(stat) 0.06(syst) A = 0.07 0.15(stat) 0.05(syst)
“sin21” = 0.50 0.21(stat) 0.06(syst) A = 0.07 0.15(stat) 0.05(syst)
KS and KL combined background subtracted good tags t –t for KL
t distribution and asymmetry
_535M BB
Consistent with the SM (~1lower) Consistent with Belle 2005
(Belle2005: “sin21” = +0.44
The most precise measurement now
Consistent with the SM (~1lower) Consistent with Belle 2005
(Belle2005: “sin21” = +0.44
The most precise measurement now
unbinned fitSM
BELLE-CONF-0647BELLE-CONF-0647
28
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00 KK00
• Obtain CP parameters for 2-body and 3-body modes simultaneously by time-dependent Dalitz fit
_347M BB
KKKS
KKKS
KKKL
1516 65 KKK0signal
1516 65 KKK0signal
29K0: sin2eff = +0.12 ± 0.31(stat) ± 0.10 (syst)K0: sin2eff = +0.12 ± 0.31(stat) ± 0.10 (syst)
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00 KK00
measurement (not sin2)
Rejected(within SM)4.6
30
Belle 2006: Belle 2006: BB00 ''KK0 0 signalsignal
1421 46 'KS signal
1421 46 'KS signal
454 39 'KL signal
454 39 'KL signal
_535M BB
(bkg subtracted)B0 massB0 momentum
31
Belle 2006: tBelle 2006: tCPCPV in V in BB00 ''KK00
“sin21” = 0.64 0.10(stat) 0.04(syst) A = 0.01 0.07(stat) 0.05(syst)
“sin21” = 0.64 0.10(stat) 0.04(syst) A = 0.01 0.07(stat) 0.05(syst)
_535M BB
First observation of tCPV (5.6in a single b s mode
Consistent with the SM Consistent with Belle 2005
(Belle 2005: “sin21” = +0.62
First observation of tCPV (5.6in a single b s mode
Consistent with the SM Consistent with Belle 2005
(Belle 2005: “sin21” = +0.62
t distribution and asymmetry
''KS and ''KL combined background subtracted good tags t –t for ''KL BELLE-CONF-0647BELLE-CONF-0647
32
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00 ''KK00
Cf. BaBar 2005: “sin2” = +0.36 0.13 0.03
“sin2” = 0.55 0.11(stat) 0.02(syst) A = 0.15 0.07(stat) 0.03(syst) “sin2” = 0.55 0.11(stat) 0.02(syst) A = 0.15 0.07(stat) 0.03(syst)
“sin2” 4.9 from zero.
_347M BB
33
Belle 2006: tBelle 2006: tCPCPV in V in BB00 KKSSKKSSKKSS
“sin21” = 0.30 0.32(stat) 0.08(syst) A = 0.31 0.20(stat) 0.07(syst)
“sin21” = 0.30 0.32(stat) 0.08(syst) A = 0.31 0.20(stat) 0.07(syst)
185 17 KSKSKS signal
185 17 KSKSKS signal
B0 mass
_535M BB
t distribution and asymmetry
background subtracted good tags
BELLE-CONF-0647BELLE-CONF-0647
34
“sin2” = 0.66 0.26(stat) 0.08(syst) A = 0.14 0.22(stat) 0.05(syst) “sin2” = 0.66 0.26(stat) 0.08(syst) A = 0.14 0.22(stat) 0.05(syst)
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00 KKSSKKSSKKSS
176 17 KSKSKS signal
176 17 KSKSKS signal
t distribution and asymmetry
_347M BB
35
Results for other b Results for other b s modes s modes(~20sec/result)(~20sec/result)
36
Belle 2006: tBelle 2006: tCPCPV in V in BB00 ff00KKSS
“sin21” = 0.23(stat) 0.11(syst) A = 0.15(stat) 0.07(syst)
“sin21” = 0.23(stat) 0.11(syst) A = 0.15(stat) 0.07(syst)
_535M BB
377 25 f0KS signal377 25 f0KS signal
Raw symmetryB0 mass
good tags mass
BELLE-CONF-0648BELLE-CONF-0648
37
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00 KKSS
“sin2” = 0.33 0.26(stat) 0.04(syst) A = 0.20 0.16(stat) 0.03(syst) “sin2” = 0.33 0.26(stat) 0.04(syst) A = 0.20 0.16(stat) 0.03(syst)
425 280KS signal
425 280KS signal
_347M BB
38
Belle 2006: tBelle 2006: tCPCPV in V in BB00 KKSS
“sin21” = 0.35(stat) 0.08(syst) A = 0.14(stat) 0.05(syst)
“sin21” = 0.35(stat) 0.08(syst) A = 0.14(stat) 0.05(syst)
_535M BB
515 320KS signal
515 320KS signal
Raw symmetryB0 mass
good tags
BELLE-CONF-0648BELLE-CONF-0648
39
Belle 2006: tBelle 2006: tCPCPV in V in BB00 KKKKKKSS
“sin21” = 0.15(stat) 0.03(syst) (CP-even) A = 0.10(stat) 0.05(syst)
“sin21” = 0.15(stat) 0.03(syst) (CP-even) A = 0.10(stat) 0.05(syst)
_535M BB
840 34 KS signal
840 34 KS signal
Raw symmetry
B0 mass
good tags
+0.210.13
BELLE-CONF-0648BELLE-CONF-0648
40
Belle 2006: tBelle 2006: tCPCPV in V in BB00 KKSS
“sin21” = 0.46(stat) 0.07(syst) A = 0.29(stat) 0.06(syst)
“sin21” = 0.46(stat) 0.07(syst) A = 0.29(stat) 0.06(syst)
_535M BB
118 18 KS signal
118 18 KS signal
B0 mass
Raw symmetry
good tags
BELLE-CONF-0648BELLE-CONF-0648
41
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00 KKSS
“sin2” = 0.62 (stat) 0.02(syst) A = 0.43 (stat) 0.03(syst) “sin2” = 0.62 (stat) 0.02(syst) A = 0.43 (stat) 0.03(syst) +0.23
0.25
+0.250.30
142 17 0KS signal142 17 0KS signal
_347M BB
42
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00 KKSS
“sin2” = 0.17 0.52(stat) 0.26(syst) A = 0.64 0.41(stat) 0.25(syst) “sin2” = 0.17 0.52(stat) 0.26(syst) A = 0.64 0.41(stat) 0.25(syst)
111 19KS signal
111 19KS signal
quasi 2-body approach (restricting tothe region dominated by 0)
_347M BB
43
2006: 2006: 11 with with bb ss Penguins PenguinsSmaller than bccs in all of 9 modes
Smaller than bccs in all of 9 modes
Theory tends to predictpositive shifts(originating from phasein Vts)
Naïve average of all b s modes
sin2eff = 0.52 ± 0.052.6 deviation betweenpenguin and tree (b s) (b c)
Naïve average of all b s modes
sin2eff = 0.52 ± 0.052.6 deviation betweenpenguin and tree (b s) (b c)
More statistics crucial for mode-by-mode studies
44
Standard penguin (bird), or something else (rabbit may be) ?
More statistics crucial for mode-by-mode studies
45
Other handles to search for new physicsOther handles to search for new physicswith penguin diagrams with penguin diagrams
• B0 KsKs (b d penguin): even higher statistics needed
• B sum rule [Gronau, Rosner 2005]• A(K00) = A(K) + A(K0+) – A(K+0)
• B0 Ks0 (electromagnetic penguin)• New physics may lead to right handed currents. This can be
investigated using time-dependent CPV measurements of b s decays and will be discussed in Barlow's talk.
S ~ 0 expected in SM
0.120.110.160.04
46
22
1 “beam”1 “beam”
2 “banana”2 “banana”
47
ttCPCPV and V and 2 2 (())
13
2VudV*ub
VtdV*tb
VcdV*cb
B0
d
b–
d–
bt
–tB0
–V*
tb Vtd
V*tbVtd
Mixing diagram Decay diagram (tree)
B0
b–
d du–
d–u
/
/Vud
V*ub
With the tree diagram only
S = +sin22
A = 0
S = +sin22
A = 0
3 possibilities: 3 possibilities:
48
Belle 2006: B0→+− decay (CP asymmetry)
04.010.061.0
05.008.055.0
S
A
first error: stat., second: syst.
background subtracted
+−
yie
lds
+−
asy
mm
etr
y
Large Direct CP violation (5.5)
Large mixing-induced CP violation (5.6)
confidence level contour
H. IshinoH. Ishino
BELLE-CONF-0649BELLE-CONF-0649 _535M BB
1464±65 signal events
49
S. TelnovS. Telnov
BaBar 2006: tBaBar 2006: tCPCPV in V in BB00
confidence level contour
Evidence for CP violation (3.6)
Direct CP violation not yet observed
02.014.053.0
03.011.016.0
S
A
50
History of B0→+− decay
2.3 diff. btw. Belle and BaBar
(C = A)
51
The results support the expectation from SU(3) symmetry that
)(3~)( KAA CPCP
018.0115.0)( KACPHFAG summer 2005
Interpretation: Direct CP violation+SU(3)
N.G. Deshpande and X.-G. He, PRL 75, 1703 (1995)
M. Gronau and J.L. Rosner, PLB 595, 339 (2004)
3.0~)( CPA
ICHEP2006 World Average
07.039.0~)( CPA
52
:tough bananas:tough bananas
• A world average observation of large direct CPV• Large penguin diagram (P) ~ Tree diagram (T)• Large strong phase difference between P and T
B0d
d
b
du
u
W
g +
-
VtdV*
tb
t d
2222 )2sin(1 effeffAS 2222 )2sin(1 effeffAS
53
Isospin analysis: flavor SU(2) symmetryIsospin analysis: flavor SU(2) symmetry
• Model-independent (symmetry-dependent) method• SU(2) breaking effect well below present statistical errors
2222 )2sin(1 effeffAS 2222 )2sin(1 effeffAS“Penguin pollution” can be removed by isospin analysis“Penguin pollution” can be removed by isospin analysis
[Gronau-London 1990]
54
2 constraints from B0→+− decay
inputsB(+0) = (5.75 0.42)B(+-) = (5.20 0.25) 10-6
B(00) = (1.30 0.21) A(00) = +0.35 0.33S(+-) = 0.59 0.09A(+-) = +0.39 0.07
inputsB(+0) = (5.75 0.42)B(+-) = (5.20 0.25) 10-6
B(00) = (1.30 0.21) A(00) = +0.35 0.33S(+-) = 0.59 0.09A(+-) = +0.39 0.07
No stringent constraintobtained with system alone need and
55
ttCPCPV with BV with B00
• Even worse on first sight ...– Dirty final state: – Mixture of CP = +1 and 1: need to know each fraction
(A++A-)/√2
A||
(A+-A-)/√2
A⊥
A0
+
+A0
A+
A-
+1
1
1
CP
vector vector
56
Isospin analysis with B Isospin analysis with B • Branching fraction for B0 is larger than
• Branching fraction for B0 is small (<1.1x10-6)– small penguin pollution
• ~100% longitudinally polarized (~pure CP-even state)– no need for elaborate angular analysis
• No significant 3-body/4-body contamination
• Dirty final states including 0
– OK in the clean e+e environment
the best mode as of summer 2005the best mode as of summer 2005
57
BaBar2006: tBaBar2006: tCPCPV in B V in B
58
BaBar2006: B BaBar2006: B (cont.)(cont.)
• B0 branching fraction: indication at 3.0
• B+ branching fraction
59
2 constraints from B0→+− decay
New branching fraction
Isospin triangle now closed (new )
constraint on 2 becomes less stringent.
60
BaBar2006: B BaBar2006: B Dalitz analysis Dalitz analysis
Preliminary result in 2004 (16 parameters ignoring ) is superseded.
Interferenceinfo. onstrong phasedifference
B0
B0
61
ICHEP2006: BaBar(ICHEP2006: BaBar(////) + Belle() + Belle(//))
Global Fit = [ 98 ] º +5-19
/2 = [93 ]+119 consistent with a global fit w/o /2
62
• sets a “window” around 90• chooses the correct position inside
the window: revival of ! • essential to suppress 2~ 0 or 180
• Good agreement b/w the CKM fit ( determined by others) and the direct measurements
• Still a lot to do– solution around 0 or 180, which requires |P/T|~1, can/should be much more
suppressed • e.g. Model-independent constraint using K* (robust against SU(3) breaking)
[Beneke-Gronau-Rohrer-Spranger 2006]– subtleties in statistical analyses with small statistics– uncertainty in background modeling, unknown phases etc.
//22: Discussions: Discussions
63
Belle 2006: Belle 2006: 22 from B from B Dalitz analysis + isospin (pentagon) analysis Dalitz analysis + isospin (pentagon) analysis
• 26(Dalitz) + 5(Br(), Br(), Br(), A(), and A())
2 (degree)
1-C
L
Results
mass
helicity
/2 = [83 ]+12 (1)
(no constraint at 2
will be included in the world averageBELLE-CONF-0650BELLE-CONF-0650
_449M BB
64
SummarySummary
• ttCPCPV allows a direct access to fundamental EW parameters V allows a direct access to fundamental EW parameters with small hadronic uncertainties in spite of large hadronic with small hadronic uncertainties in spite of large hadronic uncertainties in branching fractions !uncertainties in branching fractions !
• sin2sin211 now determined with 4% accuracy now determined with 4% accuracy• ttCPCPV in b V in b s: interesting (and tantalizing) hint of deviation from SM s: interesting (and tantalizing) hint of deviation from SM
expectations: only an order of magnitude more data will resolve the expectations: only an order of magnitude more data will resolve the issueissue
• With improved statistics and sophisticated analyses, it has become With improved statistics and sophisticated analyses, it has become clear that clear that 22 is harder to determine than we thought at ICHEP2004; is harder to determine than we thought at ICHEP2004; however, statistics are still the main obstacle.however, statistics are still the main obstacle.
My talk is just a status report !The best of two B factories is yet to come !
My talk is just a status report !The best of two B factories is yet to come !
tCPV Beautyin
Backup SlidesBackup Slides
66
Both Both 11// and and 22// Determined from Determined from
Measurements ofMeasurements ofTime-dependent Time-dependent CPCP Asymmetries Asymmetries
in the in the BB Meson System Meson System
67
Belle 2006: Systematic errors of BBelle 2006: Systematic errors of B00J/J/KK00
Sin21 A
Vertexing 0.012 0.009
Flavor tagging 0.004 0.003
t Resolution 0.006 0.001
Physics parameters. 0.001 0.001
Possible fit bias 0.007 0.004
BG fractions (J/KS) 0.003 0.001
BG fractions (J/KL) 0.005 0.002
BG t 0.001 0.001
Tag-Side interference 0.001 0.009
total 0.017 0.014
68
J/K0
J/KS
J/KL
q=+1q=-1
SVD1SVD2
ntrktag>=6ntrktag=5ntrktag=4ntrktag=3ntrktag=2ntrktag=1
r0.875-1.0000.750-0.8750.625-0.7500.500-0.6250.250-0.5000.100-0.250
69
KEKB Integrated luminosity
B0 J/ KS0
B0 J/ KL0
70
2006: World Average2006: World Average
0.6750.026
71
2006: BaBar + Belle2006: BaBar + Belle
No direct CPV in the SM: will see with more data No direct CPV in the SM: will see with more data
~2 differenceb/w BaBar and Belle
72
BaBar:
statistical error: 0.034 0.026
More precisemeasurementspossible withmore data !
More precisemeasurementspossible withmore data !
K.GeorgeK.George
73
Belle 2006: Belle 2006: BB00 KKSS helicityhelicity
_532M BB
Consistent with the model used in the analysis [P-wave () + small non P-wave component obtained from Dalitz analysis]
Consistent with the model used in the analysis [P-wave () + small non P-wave component obtained from Dalitz analysis]
74
Belle 2006: tBelle 2006: tCPCPV in V in BB00 KK00 _532M BB
KSKS KL
KL
“sin21” = +0.500.23(stat)“sin21” = +0.500.23(stat) “sin21” = +0.460.56(stat)“sin21” = +0.460.56(stat)
75
Belle 2006: tBelle 2006: tCPCPV in V in BB00 ''KK00 _532M BB
'KS'KS 'KL
'KL
“sin21” = +0.670.11(stat)“sin21” = +0.670.11(stat) “sin21” = +0.480.24(stat)“sin21” = +0.480.24(stat)
76
Belle 2006: tBelle 2006: tCPCPV in V in BB00 ''KK00
“sin21” with subsamples“sin21” with subsamples
Errors are statistical only
77
Belle 2006: tBelle 2006: tCPCPV in V in BB00 ''KK00
Significance of tCPVSignificance of tCPV
S = 0 ruled outwith >5.6at any A
78
79
80
B0→+− decay
C =−A
2.3 diff. btw. Belle and BaBar
81
82
83
84
(1.4 b/w BaBar and Belle)
85
86
87
88
UTfit: UTfit: from from , , , ,
All combined
More SlidesMore Slides
90
The Kobayashi-Maskawa weak phaseThe Kobayashi-Maskawa weak phase
(0,0) (0,1)
_ _(, )
1()3()
2()
Normalized with |VcdVcb*|
= (12/2)
= (12/2)
100
010
001
CKMCKM VV
In particular, Vtd = |Vtd|exp(i1) Vub = |Vub|exp(i3)
A3
3 generations CP-violating phase3 generations CP-violating phase
91
What’s What’s CPCP violation ? violation ?It is a partial rate asymmetry !It is a partial rate asymmetry !
|B |f
1 = |1|eisei
2 = |2|eis’ei’
)'cos()'cos(||||2||||
)'sin()sin(|||2
)()(
)()(22 ss
ss
fBfB
fBfB
Asym
|B |f
1 = |1|eisei
2 = |2|eis’ei’
CP
’: weak phase diff. : previous slide ss’: static phase diff. : FSI, Resonance, m
’: weak phase diff. : previous slide ss’: static phase diff. : FSI, Resonance, m
92
Wolfenstein parameterizationWolfenstein parameterization
93
Inclusive e’s Inclusive e’s at the at the ϒϒ(4S)(4S)
2.0 2.2 2.4 2.6
Belle
CLEO result in ~1980
Tributefrom S. Olsen
94
Back to the FutureBack to the Future1981 1981 2006 2006
95
PEP-II
KEKB
Belle
BaBar
9GeV (e) 3.1GeV (e+)peak luminosity: 1.121034cm2s1
Two Asymmetric-energy Two Asymmetric-energy BB Factories Factories
8GeV (e) 3.5GeV (e+) peak luminosity: 1.651034cm2s1
world record !
Charged tracking/vertexingCharged tracking/vertexing • • SVD:SVD:
(-7/03) 3-layer DSSD Si µstrip(-7/03) 3-layer DSSD Si µstrip (8/03-) 4-layer(8/03-) 4-layer • • CDC: 50 layers (He-ethane)CDC: 50 layers (He-ethane)
Hadron identificationHadron identification • • CDC: dE/dxCDC: dE/dx • • TOF: time-of-flightTOF: time-of-flight • • ACC: Threshold Cerenkov ACC: Threshold Cerenkov
(aerogel)(aerogel)Electron/photonElectron/photon • • ECL: CsI calorimeterECL: CsI calorimeter
Muon/KMuon/KLL • • KLM: Resistive plate KLM: Resistive plate
counter/ironcounter/iron
Charged tracking/vertexingCharged tracking/vertexing • • 5-layer DSSD Si µstrip5-layer DSSD Si µstrip • • 40 layers (He-isobutane)40 layers (He-isobutane)
Hadron identificationHadron identification • • tracker: dE/dxtracker: dE/dx • • DIRC imaging Cerenkov DIRC imaging Cerenkov
Electron/photonElectron/photon • • CsI calorimeterCsI calorimeter
Muon/KMuon/KLL • • Instrumented flux returnInstrumented flux return
96
PEP-II & BaBarPEP-II & BaBar• Lmax = 1.12 X 1033 cm–2s–1
Ldt = 371 fb–1@{Υ(4S)+off(~10%)}• (>3.7x108 B events)
Charged tracking/vertexingCharged tracking/vertexing • • 5-layer DSSD Si µstrip5-layer DSSD Si µstrip • • 40 layers (He-isobutane)40 layers (He-isobutane)
Hadron identificationHadron identification • • tracker: dE/dxtracker: dE/dx • • DIRC imaging Cerenkov DIRC imaging Cerenkov
Electron/photonElectron/photon • • CsI calorimeterCsI calorimeter
Muon/KMuon/KLL • • Instrumented flux returnInstrumented flux return
11 nations, 80 institutes, 623 persons
97
e+ source
Ares RF cavity
Belle detector
World record: L = 1.6 x
1034/cm2/sec
SCC RF(HER)
ARES(LER)
The KEKB ColliderThe KEKB Collider
8 x 3.5 GeV 22 mrad crossing angle
~1 km in diameter
Mt. Tsukuba
KEKBBelle
since 1999
98
Belle detectorBelle detector
KL detector14/15 layer RPC+Fe
Electromagnetic CalorimeterCsI(Tl) 16X0
Aerogel Cherenkov Counter n = 1.015~1.030
Si Vertex Detector4-layer DSSD
TOF counter
3.5 GeV e+
Central Drift Chamber momentum, dE/dx 50-layers + He/C2H6
charged particle tracking
K/ separation
K/ separation
B vertexMuon / KL identification
, 0 reconstructione+-, KL identification
8.0 GeV e-
99
= 0.425 (Belle) 0.56 (BaBar)
Principle of tPrinciple of tCPCPV measurementV measurementCP-side
1. Fully reconstruct one B-meson which decays to CP eigenstate
electron
positron
(4S)resonance B1
B2
+
-
KS/L
J/
100
= 0.425 (Belle) 0.56 (BaBar)
Principle of tPrinciple of tCPCPV measurementV measurement
t z c
CP-side
Flavor tag and vertex reconstr
uction
Flavor tag and vertex reconstr
uction
1. Fully reconstruct one B-meson which decays to CP eigenstate2. Tag-side determines its flavor (effective efficiency = 30%)3. Proper time (t) is measured from decay-vertex difference (z)
electron
positron
(4S)resonance B1
B2
+-
K+
-0
D
+
-
KS/L
J/
z ~ 200m(Belle)
B0
B0_
101
b g s modes and their “cleaness” in SMb g s modes and their “cleaness” in SM
taken from a review “CP violation” in PDG2005 (D.Kirkby, Y.Nir)
pure treeb cud DCP 0 DCPKs (Vcb*Vud)T + (Vub*Vcd)T 2
+ ucd
102
Experimental ChallengeExperimental Challenge
B0 J/KS
B0 KS
Tree
Penguin
We need1) large number of BB pairs2) additional background rejection
Event Shape Event Shape
e e qq
(Jet-like)e e 4 S B B
(Spherical)
Mbc
Signal Likelihood
103
Signal Likelihood (LHR) projection
Mbc projection
LHRMbc
Clear separation betweensignal and background
Clear separation betweensignal and background
BB00 KsKs
Ks signal
Ks signal