BELLE
L ATEST R ESULTS FROM B ELLE
AND
P LANS FOR A S UPER B FACTORY
Tim Gershon
University of Warwick
January 24, 2006
Tim Gershon
University of Oxford Seminar
January 24, 2006
Contents
BELLE
• KEK-B and Belle
• Summer 2005 highlights
(http://belle.kek.jp/conferences/CONF2005/)
– direct CP violation
– measurements of UT angles
– penguin dominated processes
• Super B Factory
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Belle Collaboration
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
KEK
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Integrated Luminosity
University of Oxford Seminar
January 24, 2006
-2 -1
Increase of Peak Luminosity
14
1.627 10 /cm /s on 2005/12/19 (KEKB)
12
1.0025 10 /cm /s on 2005/10/9 (PEP-II)
34
33
-2 -1
Peak luminosity (10 cm s )
16
Peak luminosity (cm s )
Luminosity Trends
BELLE
34
2
2
10
8
6
10 34
10
Peak Luminosity trends in last 30 years
PEP II
33
CESR
10 32
ISR
PETRA
10
KEKB
31
DORIS
TEVATRON
LEP2
PEP
TRISTAN
HERA
LEP1
SPEAR
4
10
30
SppS
2
0
Tim Gershon
2000
2002
2004
2006
Year
10 29
1970
1975
University of Oxford Seminar
1980
1985
1990
1995
2000
2005
Year
January 24, 2006
BELLE
Tim Gershon
Belle Detector
University of Oxford Seminar
January 24, 2006
Inner Detector Upgrade - Summer 2003
BELLE
I MPROVED R ESOLUTION !
Number of silicon DSSDs
3 layers
→
4 layers
Radius of beam pipe
r = 2.0 cm → r = 1.5 cm
Radiation hardness
1 MRad
→ > 20 MRad
Laboratory polar angle coverage
23◦ < θ < 139◦ → 17◦ < θ < 150◦
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Search for Θ(1540)+ Using Kaon Interactions
397 fb−1
PLB 632, 173 (2006)
. . . no pentaquarks found
Tim Gershon
University of Oxford Seminar
January 24, 2006
CKM Phenomenology
BELLE



1 − λ2/2
λ
Vud Vus Vub



VCKM =  Vcd Vcs Vcb  ∼ 
−λ
1 − λ2/2
Vtd Vts Vtb
Aλ3(1 − ρ − iη)
−Aλ2
Aλ3(ρ − iη)
Aλ2
1



where A, λ, ρ, η are Wolfenstein parameters
∗
VCKM = 1):
From unitarity (VCKM
∗ +V V∗ +V V∗ =0
VudVub
cd cb
td tb
(ρ,η)
The Unitarity Triangle
φ1 ↔ β
φ2 ↔ α
φ3 ↔ γ
VudVub*
VcdVcb*
φ3
(0,0)
Tim Gershon
University of Oxford Seminar
φ2
VtdVtb*
VcdVcb*
φ1
(1,0)
January 24, 2006
The Purpose of the B Factory
BELLE
• Within the Standard Model, only B system has large CP violation
• Hadronic parameters (τB , ∆md) ⇒ CP effects accessible
• e+ e− collisions at high luminosity
– large data sample
– clean environment
reconstruct almost any decay mode (even with neutrinos)
• Precise test of quark mixing & CP violation within SM
• Search for new physics
• Copious samples of τ pairs, D mesons and other particles also produced
⇒ broad physics program
Tim Gershon
University of Oxford Seminar
January 24, 2006
Categories of CP Violation
BELLE
• Usually discussed in the context of neutral B decays
B0
• Consider B 0/B̄ 0 decaying to a CP eigenstate
• Define λCP = pq Ā
A
– p, q from B 0 − B̄ 0 mixing
– Standard Model : pq ∼ e−2φ1
A
∆m
(usual phase convention)
–
fCP
A
–0
B
• Three categories of CP violation
1
2
3
|q/p| 6= 1
Ā/A 6= 1
Im(λCP ) 6= 0
CP V in mixing
CP V in decay (direct CP V )
CP V in mixing—decay interference
• With amplitude analysis can also consider
2′
Tim Gershon
Im(Ā/A) 6= 0
CP V in decay amplitude to Q2B state
University of Oxford Seminar
January 24, 2006
BELLE
Experimental Technique
• For most modes, use two kinematic variablesq
to identify signal
2
− p2
∆E = EB − Ebeam
Mbc = Ebeam
B
• Put event-shape variables into likelihood ratio to reject background
• Particle ID from ACC, TOF & CDC used to separate K/π
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Direct CP Violation
Tim Gershon
University of Oxford Seminar
January 24, 2006
Direct CP V in B 0 → K +π −
600
K−π+
500
400
300
700
600
500
400
300
200
200
100
100
0
5.2
5.25
5.3
K+π−
0
5.2
5.25
2
− +
Kπ
500
400
300
700
600
400
300
200
100
100
0
0.5
∆E (GeV)
K+π−
500
200
0
Mbc (GeV/c )
Entries/20MeV
Entries/20MeV
600
5.3
2
Mbc (GeV/c )
700
BELLE-CONF-0523
Entries/2MeV/c2
700
357 fb−1
Entries/2MeV/c2
BELLE
0
0
0.5
∆E (GeV)
Significance: 4.97σ
ACP K +π − = −0.113 ± 0.022(stat) ± 0.008(syst)
Tim Gershon
University of Oxford Seminar
January 24, 2006
Direct CP V in B + → K +π 0
Entries/2MeV/c2
200
200
Kπ
- 0
175
K+π0
175
150
150
125
125
100
75
75
50
50
25
25
0
5.2
5.25
0
5.2
5.3
2
100
K-π0
80
60
40
20
5.3
Mbc (GeV/c )
Entries/15MeV
Entries/15MeV
5.25
2
Mbc (GeV/c )
100
BELLE-CONF-0523
100
0
357 fb−1
Entries/2MeV/c2
BELLE
K+π0
80
60
40
20
-0.25
0
0.25
∆E (GeV)
0
-0.25
0
0.25
∆E (GeV)
ACP K + π 0 − ACP K + π −
3.1σ from zero
ACP K +π 0 = 0.04 ± 0.04(stat) ± 0.02(syst)
Tim Gershon
University of Oxford Seminar
January 24, 2006
Direct CP V in B + → K +π +π −
BELLE
± + - data
- total background
- continuum
1200
iδj
aj e = CP conservating complex amplitude
bj eiφj = CP violating part
η = +1(−1) for B + (B − )
Aj = Breit-Wigner (etc.) dependence
- BB total
800
- BB charmless
400
0
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
∆E (GeV)
25
(b)
2
2bj cos φj
1+b2
j
+
(δ=0)
A
a
φ
ab
A−
15
10
2
+ -
ACP
=−
j
4
• Can translate to usual CP asymmetry
M (π π ) (GeV /c )
20
Belle-Preprint-2005-36
• Parametrize each contributing
resonant
term as
aj eiδj 1 + ηbj eiφj Aj
–
–
–
–
±
B →K π π
1600
Events/(10 MeV)
• 4286 ± 99 signal events
2000
357 fb−1
• Veto major charm(onium) contributions
to K +π +π − final state
5
0
0
5
10
15
20
25
30
M (K π ) (GeV /c )
2
Tim Gershon
University of Oxford Seminar
+ -
2
4
January 24, 2006
Direct CP V in B + → K +π +π −
BELLE
357 fb−1
(a)
200
300
150
100
200
50
0
100
0
0.6
1
2
0.8
1.0
1.2
3
4
M(K π ) (GeV/c )
+ -
1.4
2
1.6
5
Events/(50 MeV/c2)
Events/(50 MeV/c2)
400
40
(b)
400
30
300
20
200
10
100
0
0
3.2
0
1
2
3.3
3.4
3
3.5
4
5
M(π π ) (GeV/c )
+ -
2
Contributions from K ∗(892)0 π +, K0∗(1430)0 π +, ρ0K +, ωK +, f0K +,
f2(1275)K + , fX (1300)K + , χc0K + & non-resonant terms
Belle-Preprint-2005-36
Fit first without CP terms to establish model (bj = 0)
f0(980) parametrized by Flatté lineshape, fX (1300) assumed scalar (f0(1370)?)
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Direct CP V in B + → K +π +π −
357 fb−1
First evidence for direct CP V in charged B decays
Belle-Preprint-2005-36
• Statistical significance calculated as
q
−2 ln(L0/Lmax)
• Largest systematics from model uncertainty
Tim Gershon
University of Oxford Seminar
January 24, 2006
Direct CP V in B + → K +π +π −
BELLE
357 fb−1
Asymmetry in the ρ region clearly visible in the data
(a)
80
60
40
20
0.5
0.6
0.7
0.8
0.9
1.0
1.1
80
40
20
0.5
0.6
M(π π ) (GeV/c )
+ -
Events/(0.05 GeV/c2)
Events/(0.02 GeV/c2)
B →K π π
+ + -
(b)
80
60
40
20
0.5
0.6
0.7
0.8
0.9
1.0
M(π π ) (GeV/c )
+ -
Tim Gershon
0.8
0.9
+ -
1.0
1.1
2
120
-
- - +
1.1
1.2
(e)
100
80
60
40
20
0
0.4
1.2
B → K π π
ππ
cos(θhel )>0
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
M(π+π-) (GeV/c2)
2
160
100
+
0
0.4
0.7
140
M(π π ) (GeV/c )
2
120
100
(c)
60
0
0.4
1.2
- - +
B →K π π
ππ
cos(θhel )<0
+
80
+ + -
Events/(0.05 GeV/c2)
0
0.4
B → K π π
ππ
cos(θhel )<0
-
Events/(0.05 GeV/c2)
B → K π π
- - +
Events/(0.05 GeV/c2)
100
160
100
-
(d)
60
40
20
0
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
M(π π ) (GeV/c )
+ -
2
University of Oxford Seminar
1.2
140
120
B →K π π
ππ
cos(θhel )>0
+
+ + -
(f)
100
80
60
Belle-Preprint-2005-36
Events/(0.02 GeV/c2)
120
40
20
0
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
1.2
M(π+π-) (GeV/c2)
January 24, 2006
BELLE
Direct CP Violation — Summary
Direct CP violation seen by Belle:
• B 0 → K +π − (∼ 10%
• B 0 → π +π − (∼ 50%
• B + → ρ0K + (∼ 30%
Tim Gershon
∼ 5σ)
∼ 4σ)
∼ 4σ)
University of Oxford Seminar
January 24, 2006
BELLE
Measurements of UT Angles
Tim Gershon
University of Oxford Seminar
January 24, 2006
Key: Redundancy
BELLE
(ρ,η)
VudVub*
VcdVcb*
φ3
φ2
(0,0)
VtdVtb*
VcdVcb*
φ1
(1,0)
φ1
φ2
φ3
b → cc̄s (J/ψKS )
b → uūd (π +π −, ρ+ρ−)
b → cūs/uc̄s (DK −)
b → cūd (Dπ 0)
b → uūs vs. b → uūd (Kπ vs. ππ)
2φ1 + φ3
b → cc̄d (J/ψπ 0, D+D−)
b → sq̄q (φKS )
b → cūd/uc̄d (D+π −)
. . . and many others!
Tim Gershon
University of Oxford Seminar
January 24, 2006
φ3 from B → DK
BELLE
• Can access φ3 via interference between B − → D0K − & B − → D̄0K −
Bigi & Sanda; Gronau, London & Wyler
• Reconstruct D in final states accessible to both D0 and D̄0
∗
B − → D0K − ∼ VusVcb
s
W
u
b
c
u
u
COLOUR ALLOWED
A — amplitude
rB = ASUPPRESSED/AFAVOURED
∼ 0.1 − 0.2
δB — strong phase difference
Tim Gershon
∗
B − → D̄0K − ∼ VcsVub
b
u
W
c
s
u
u
COLOUR SUPPRESSED
2A (B −
A (B −
DCPK−)
0 −
DK )
A (B −
δ
φ3
δ φ
0 −
DK )
3
University of Oxford Seminar
January 24, 2006
φ3 from B → DK: Final States
BELLE
• Ultimately aim to use many states and combine results
• Inclusive analyses can be performed but sensitivity is diluted
Reconstruct modes exclusively, where possible
Use amplitude analysis (not, eg., Q2B analysis) where possible
• To extract φ3, need D decay “model”
crucial rôle of charm factory
• Modes used so far
1. CP even (mainly K +K −)
2. CP odd (mainly KS π 0)
3. Doubly Cabibbo suppressed states (Kπ)
4. Multibody final states (KS ππ)
• Modes that may be used in future
∗ KS K +K −, π +π −π 0, KS π ±K ∓, K ±π ∓π 0, KS π +π −π 0, . . .
Tim Gershon
University of Oxford Seminar
January 24, 2006
Parameters
BELLE
• CP violation effects depend on
φ3 : weak phase difference between B decay amplitudes
δB : strong phase difference between B decay amplitudes
rB : relative magnitude of B decay amplitudes
δD : (strong phase difference of D decay amplitudes)
rD : (relative magnitude of D decay amplitudes)
• For multibody D decays, last two described by decay model
• D decay model also includes assumptions of
– no mixing
– no CP violation
. . . well motivated and tested (effects can be included)
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Principle of the Multi-Body Analysis
A. Giri, Y. Grossman, A. Soffer & J. Zupan, PRD 68, 054018 (2003)
A. Poluektov et al. (Belle Collaboration), PRD 70, 072003 (2004)
• Consider D̄0 → KS π +π −
2)
→ define amplitude at each Dalitz plot point as f (m2
,
m
−
+
where m+ = mK π + , m− = mKS π −
S
• Consider D0 → KS π +π −
2
→ amplitude at each Dalitz plot point is f (m2
− , m+ )
2
2
• f (m+ , m−) can be measured using flavour tagged D mesons
+
+
−
• Consider B → KS π π
K+
D
2
i(δB +φ3 )f (m2 , m2 )
→ amplitude is f (m+ , m2
−
− ) + rB e
+
• Consider B − → KS π +π − K −
D
2
i(δB −φ3 )f (m2 , m2 )
)
+
r
e
→ amplitude is f (m− , m2
B
−
+
+
• Can extract (rB , δB , φ3) from B + & B − data
Tim Gershon
University of Oxford Seminar
January 24, 2006
B ± → D (∗)K (∗)± Selection
100
Entries/10 MeV
Entries/10 MeV
B ± → D∗K ±
80
B ± → DK ∗±
22.5
20
17.5
6
7.5
4
5
2
2.5
0
-0.2 -0.15 -0.1 -0.05 0
0
-0.2 -0.15 -0.1 -0.05 0
0.05 0.1 0.15 0.2
Entries/2 MeV
16
14
14
12
10
60
12
50
10
8
40
8
6
30
6
4
20
4
10
2
0
5.2
5.22
5.24
5.26
5.28
5.3
2
Mbc (GeV/c )
276 candidate events
(209 ± 16 signal)
Tim Gershon
∆E (GeV)
∆E (GeV)
Entries/2 MeV
Entries/2 MeV
70
0
-0.2-0.15-0.1-0.05 0 0.050.10.150.2
0.05 0.1 0.15 0.2
∆E (GeV)
80
12
8
10
20
14
10
12.5
40
16
0
5.2
2
5.22
5.24
5.26
5.28
5.3
2
Mbc (GeV/c )
69 candidate events
(58 ± 8 signal)
University of Oxford Seminar
0
5.2
5.22 5.24 5.26 5.28
5.3
Mbc (GeV/c2)
56 candidate events
(36 ± 7 signal)
BELLE-CONF-0476,BELLE-CONF-0502
15
60
253 fb−1
B ± → DK ±
Entries/10 MeV
BELLE
January 24, 2006
B ± → DK (∗)±, D → KS π +π − Dalitz Plot Distributions
4
2
2
2
2
1.5
1
1
1
0.5
0.5
0.5
1.5 2 2.5 3
2
2 4
m+ (GeV /c )
2
2
1.5 2 2.5 3
2
2 4
m+ (GeV /c )
3
4
4
2
2.5
1
2
3
0.5
2.5
2
2
1
m+ (GeV /c )
4
2
2
2.5
1.5
0.5
2
m - (GeV /c )
2
4
m - (GeV /c )
2
2
4
m - (GeV /c )
2
2.5
3
1.5
m+ (GeV /c )
f (m2+ , m2−)+
rB ei(δB +φ3) f (m2− , m2+ )
f (m2− , m2+ )+
rB ei(δB −φ3 )f (m2+ , m2− )
2.5
3
B ± → DK ∗±
1
1
1
0.5
0.5
0.5
0.5
1
1.5 2 2.5 3
2
2 4
m - (GeV /c )
University of Oxford Seminar
0.5
1
1.5 2 2.5 3
2
2 4
m - (GeV /c )
2
1.5
1.5 2 2.5 3
2
2 4
m - (GeV /c )
1.5 2 2.5 3
2
2 4
m+ (GeV /c )
2.5
1.5
1
1
3
1.5
0.5
0.5
BELLE-CONF-0476,BELLE-CONF-0502
Tim Gershon
3
B ± → D∗K ±
253 fb−1
B ± → DK ±
m+ (GeV /c )
BELLE
January 24, 2006
2)
Extraction of f (m2
,
m
−
+
BELLE
253 fb−1
• Fit Dalitz plot distribution of tagged D mesons from e+ e− continuum
• Tag using charge of πs in D∗+ → D0πs+
2
4
Entries/0.02 GeV /c ×10
3
Tim Gershon
1
0 0.5 1 1.5 2 2.5 3
2
2 4
m - (GeV /c )
3
2
1
0
15
2
4
4
Entries/0.02 GeV /c ×10
3
0
3
2
Fine tuning of model
little effect on φ3
4
(ndf = 1106)
Entries/0.02 GeV /c ×10
χ2/ndf = 2.30
2
0 0.5 1 1.5 2 2.5 3
2
2 4
mππ (GeV /c )
University of Oxford Seminar
10
5
0
0 0.5 1 1.5 2 2.5 3
2
2 4
m+ (GeV /c )
BELLE-CONF-0476,BELLE-CONF-0502
3
2)
• Used model defines phase variation of f (m2
,
m
−
+
January 24, 2006
Dalitz Plot Fits
BELLE
253 fb−1
Fit B ± samples separately, float rB ei(δB ±φ3)
0.4
0.3
0.2
B →DK
-
-
0.4
-0.2
-0.2
-0.3
B →DK
+
+
1
0.5
B →DK
+
B →D K
+
*
+
0
0
-0.1
*+
0
B →D K
-
*
-
-0.5
B →DK
-
-0.4
*-
-1
-0.4
-0.6
-0.4
-0.2
0
0.2
0.4
Re(r eiθ)
276 candidate events
(209 ± 16 signal)
Tim Gershon
0.6
0.2
0.1
B ± → DK ∗±
Im(r eiθ)
Im(r eiθ)
Im(r eiθ)
B ± → D∗K ±
-0.5 -0.25
0
0.25
0.5
Re(r eiθ)
69 candidate events
(58 ± 8 signal)
University of Oxford Seminar
-1
-0.5
0
0.5
1
Re(r eiθ)
56 candidate events
(36 ± 7 signal)
BELLE-CONF-0476,BELLE-CONF-0502
B ± → DK ±
January 24, 2006
Extraction of φ3
BELLE
(recall rB and δB different for each mode)
B ± → DK ±
B ± → DK ∗±
φ3 = 75◦ ± 57◦(stat) ± 11◦(syst) ± 11◦(model)
rB = 0.12 +0.16
−0.11 (stat) ± 0.02(syst) ± 0.04(model)
δB = 321◦ ± 57◦(stat) ± 11◦(syst) ± 21◦(model)
φ3 = 112◦ ± 35◦(stat) ± 9◦(syst) ± 14◦(model)
rB = 0.25 ± 0.18(stat) ± 0.09(syst) ± 0.09(model)
δB = 353◦ ± 35◦(stat) ± 8◦(syst) ± 54◦(model)
B ± → DK ± & B ± → D∗K ± combined
+14◦
◦
φ3 = 68 −15◦ (stat) ± 13◦(syst) ± 11◦(model)
Tim Gershon
University of Oxford Seminar
BELLE-CONF-0476,BELLE-CONF-0502
B ± → D∗K ±
φ3 = 64◦ ± 19◦(stat) ± 13◦(syst) ± 11◦(model)
rB = 0.21 ± 0.08(stat) ± 0.03(syst) ± 0.04(model)
δB = 157◦ ± 19◦(stat) ± 11◦(syst) ± 21◦(model)
253 fb−1
Avoid fit likelihood errors → use frequentist approach to obtain confidence regions
January 24, 2006
Time-Dependent CP Violation Phenomenology
BELLE
• Interference between different paths to a final state ⇒ time-dependent CP violation
• Consider B 0/B̄ 0 decaying to a CP eigenstate
B0
Ā
• Define λCP = pq A
A
– p, q from B 0 − B̄ 0 mixing
– Standard Model : pq ∼ e−2φ1
∆m
–
fCP
A
• Simplest scenario:
q – p = 1, Ā
A = 1 ⇒ SCP = Im(λCP )
–0
B
• At B factories, measure ∆t from decay time of other B
(tagged as B 0 (q = +1) or B̄ 0 (q = −1))
−|∆t|/τ 0
q
e
PCP (∆t) = 4τ B [1 + q {SCP sin(∆m∆t)}]
B0
Tim Gershon
University of Oxford Seminar
January 24, 2006
How To Measure Time-Dependent CP Violation
BELLE
Illustrated using B̄ 0 → J/ψKS , B 0 → D∗−µ+νµ
µ+
t=0
Ks
B
ƒ²(4S)
resonance
positron
(3.5GeV)
µ−
t=t
0
electron
(8GeV)
J/ĵ
π+
B1
B2
νµ
π−
D0
π−
B0
+
π−
K
µ+
∆Z~200µm
Tim Gershon
University of Oxford Seminar
January 24, 2006
B 0 → J/ψK 0 Selection
BELLE
2500
KS0 (π+π - )
J/ψ
386 M BB
Number of events / (0.05 GeV/c)
Events/2MeV/c2
1400
B 0 → J/ψKL
1200
1000
800
600
400
BELLE-CONF-0569
1600
357 fb−1
B 0 → J/ψKS
data
J/ΨKL
J/ΨKLX BG, KL detected
2000
J/ΨX BG, other
1500
combinatorial BG
1000
500
200
0
5.2
5.22
5.26
5.24
5.28
2
Mbc (GeV/c )
5264 ± 73 signal events
Tim Gershon
5.3
0
0
0.2 0.4 0.6 0.8
pcms
B
1
1.2 1.4 1.6 1.8
2
(GeV/c)
4792 ± 105 signal events
University of Oxford Seminar
January 24, 2006
B 0 → J/ψK 0 — ∆t Dependence
BELLE
B 0 → J/ψKL
Events / ps (good tags)
250
q = -1
200
150
100
50
-6
-4
-2
0
2
∆t (ps)
4
6
8
1
0.5
0
-0.5
-1
-8
-6
-4
-2
0
2
∆t (ps)
4
6
8
S = +0.668 ± 0.047(stat)
A = −0.021 ± 0.034(stat)
Tim Gershon
q = +1
400
q = -1
300
200
100
-8
Raw asymmetry (good tags)
Raw asymmetry (good tags)
q = +1
-6
-4
-2
0
2
∆t (ps)
4
6
8
-6
-4
-2
0
2
∆t (ps)
4
6
8
1
0.5
BELLE-CONF-0569
Events / ps (good tags)
300
-8
357 fb−1
B 0 → J/ψKS
0
-0.5
-1
-8
S = −0.619 ± 0.069(stat)
A = +0.049 ± 0.039(stat)
University of Oxford Seminar
January 24, 2006
B 0 → J/ψK 0 — World Average
BELLE
HEP 2005
PRELIMINARY
0.72 ± 0.04 ± 0.02
BaBar
PRL 94, 161803 (2005)
0.65 ± 0.04 ± 0.02
Belle
BELLE-CONF-0569
0.84 +-01..8024 ± 0.16
ALEPH
PLB 492, 259-274 (2000)
3.20 +-12..8000 ± 0.50
OPAL
BELLE-CONF-0569
HF AG
sin(2β)/sin(2φ1)
357 fb−1
Belle: sin(2φ1) = +0.652 ± 0.039 ± 0.020
EPJ C5, 379-388 (1998)
0.79 +-00..4414
CDF
PRD 61, 072005 (2000)
0.69 ± 0.03
Average
HFAG
-2
-1
0
1
2
3
World Average: sin(2φ1 ) = +0.687 ± 0.032
Tim Gershon
University of Oxford Seminar
January 24, 2006
sin(2φ1) — Constraint
BELLE
β/φ1
–
η
HF AG
HEP 2005
PRELIMINARY
1
β/φ 1
0.8
=(
1
=(
21.
2
+1. .3)˚
-1
β/φ
0.4
3
68.
0.6
7
0.2
+1
- 1. .3
2 )˚
0
-0.2
-0.2
Tim Gershon
0
0.2
0.4
0.6
0.8
University of Oxford Seminar
1
–
ρ
January 24, 2006
UT angles — Summary
BELLE
(ρ,η)
VudVub*
VcdVcb*
φ3
VtdVtb*
VcdVcb*
φ2
φ1
(0,0)
(1,0)
φ1
B 0 → J/ψK 0
φ2
B 0 → π + π − & ρ+ ρ−
+12
sin(2φ1) = +0.652 ± 0.039 ± 0.020 φ2 = 93−11 ◦
φ3
B ± → DK ±
◦
◦
◦
φ3 = 68◦ +14
−15◦ (stat) ± 13 (syst) ± 11 (model)
Ambiguities reduced by
J/ψK ∗ & D(∗) h0
π +π −π 0 D.P. (BaBar) D → KS π +π − D.P.
Tim Gershon
University of Oxford Seminar
January 24, 2006
UT angles — Summary
BELLE
η
η
Plots from UTFit Collaboration
1.2
D0π0
γ
1.2
1
∆md
∆ms
1
0.8
∆md
0.8
sin2β
sin2β
2β+γ
0.6
0.6
0.4
0.4
α
0.2
cos2β
0
0
-0.2
-0.2
-0.5
0
0.5
η
-1
1
εK
0.2
Vub
Vcb
-1
ρ
1.2
-0.5
γ
D0π0
0.5
1
ρ
∆md
∆ms
1
∆md
0.8
0
sin2β
2β+γ
0.6
0.4
0
cos2β
Vub
Vcb
-0.2
-1
Tim Gershon
α
εK
0.2
-0.5
0
0.5
University of Oxford Seminar
1
ρ
January 24, 2006
BELLE
Tim Gershon
Penguins
University of Oxford Seminar
January 24, 2006
Why Hunt Penguins?
BELLE
W
• loop diagrams ⇒ virtual particles ⇒ high masses
s,d
b
• expect new physics at TeV scale
• NP particles should appear in loops
u,c,t
• no reason for NP phases to be aligned
• many possible manifestations of NP
– b → s vs. b → d
– gluonic vs. radiative vs. electroweak
– ∆B = 2 (mixing) processes
g
γ
Z
q,l
Tim Gershon
q,l
University of Oxford Seminar
January 24, 2006
B 0 → φK 0
BELLE
data
60
120
φK L
Events / 0.02
140
BG from B mesons
100
50
40
30
BG from continuum
80
60
20
40
10
20
0
0.8
0
-0.2-0.15-0.1-0.05 0 0.05 0.1 0.15 0.2
0.85
0.9
0.95
Likelihood ratio
∆E(GeV)
180 ± 16
1
0.5
0
0
Raw Asymmetry
Raw Asymmetry
0
0.5
-0.5
0.0 < r ≤ 0.5
0.5
0
-0.5
-1
-7.5
B → φK0L
0
-0.5
0.0 < r ≤ 0.5
-1
1
0.5
0
-0.5
0.5 < r ≤ 1.0
-5
-2.5
0
2.5
5
7.5
-1
-7.5
0.5 < r ≤ 1.0
-5
-2.5
∆t(ps)
sin(2φ1eff ) = +0.44 ± 0.27 ± 0.05
Tim Gershon
1
78 ± 13
B → φKS0
-1
1
BELLE-CONF-0569
Entries / 0.01 GeV
φKL
70
1
357 fb−1
φKS
0
2.5
5
7.5
∆t(ps)
A = +0.14 ± 0.17 ± 0.07
University of Oxford Seminar
January 24, 2006
B 0 → η ′K 0
BELLE
357 fb−1
η ′KS
η ′KL
250
100
225
data
Events / 0.01
175
150
125
100
75
η’KL
80
BG from B mesons
BELLE-CONF-0569
Entries / 0.01 GeV
200
60
BG from continuum
40
20
50
25
0
0.8
0
-0.2-0.15-0.1-0.05 0 0.05 0.1 0.15 0.2
0.85
∆E(GeV)
830 ± 35
B → η′KS0
1 B0 → η′K0L
0
0.5
0.5
0
0
-0.5
0.0 < r ≤ 0.5
-1
1
0.5
0
-0.5
-1
-7.5
-0.5
0.0 < r ≤ 0.5
-1
1
0.5
0
-0.5
0.5 < r ≤ 1.0
-5
-2.5
0
2.5
5
7.5
-1
-7.5
0.5 < r ≤ 1.0
-5
-2.5
∆t(ps)
sin(2φ1eff ) = +0.62 ± 0.12 ± 0.04
Tim Gershon
1
187 ± 18
Raw Asymmetry
Raw Asymmetry
1
0.9
0.95
Likelihood ratio
0
2.5
5
7.5
∆t(ps)
A = −0.04 ± 0.08 ± 0.06
University of Oxford Seminar
January 24, 2006
b → qq̄s
BELLE
100
50
25
0.2
0
Raw Asymmetry
0
-0.5
0.0 < r ≤ 0.5
0.5
0
-0.5
0.5 < r ≤ 1.0
Tim Gershon
-2.5
0
∆t (ps)
2.5
5
7.5
0
-0.2-0.15-0.1-0.05 0 0.05 0.1 0.15 0.2
0.05 0.1 0.15 0.2 0.25 0.3
∆ E (GeV)
0.0 < r ≤ 0.5
-1
1
0.5
0.5
-0.5
0
∆t(ps)
2.5
5
7.5
0.0 < r ≤ 0.5
-1
1
-0.5
0.5 < r ≤ 1.0
20
-1
-7.5
344 ± 30
1
0.5
0
0
-2.5
30
∆E (GeV)
1 B0 → ωKS0
-0.5
0
-5
40
68 ± 13
0.5
0
50
0
-0.2-0.15-0.1-0.05 0 0.05 0.1 0.15 0.2
∆E(GeV)
1 B0 → f0 KS0
-0.5
-1
-7.5
0
145 ± 16
0.5
-5
-0.1 -0.05
536 ± 29
0.5
60
10
10
1 B0 → K+K-KS0
-1
1
5
20
∆E(GeV)
1
-1
-7.5
30
0
-0.2-0.15-0.1-0.05 0 0.05 0.1 0.15 0.2
105 ± 12
10
0.5
Raw Asymmetry/2.5 ps
0
∆E (GeV)
40
Raw Asymmetry
-0.2
15
50
Raw Asymmetry
0
75
60
Entries / 0.01 GeV
125
20
Entries / 0.01 GeV
150
30
70
20
70
Events / ( 0.0105 GeV )
40
80
80
175
10
Raw Asymmetry/2.5 ps
25
200
Entries / 0.01 GeV
Events/0.02 GeV
225
50
KS π 0
ωKS
0
-0.5
0.0 < r ≤ 0.5
-1
1
0.5
0
-0.5
0.5 < r ≤ 1.0
-5
-2.5
0
2.5
5
7.5
∆t (ps)
University of Oxford Seminar
-1
-7.5
BELLE-CONF-0569
60
f0KS
357 fb−1
K +K −KS
KS KS KS
0.5 < r ≤ 1.0
-5
-2.5
0
∆t(ps)
2.5
5
7.5
0
-0.5
0.0 < r ≤ 0.5
-1
1
0.5
0
-0.5
-1
-7.5
0.5 < r ≤ 1.0
-5
-2.5
0
∆t (ps)
2.5
5
7.5
January 24, 2006
b → qq̄s
-1.2
University of Oxford Seminar
-1
-0.8
-0.16 ± 0.09 ± 0.02
0.04 ± 0.08 ± 0.06
HEP 2005
HFAG
HFAG
HEP 2005 HEP 2005
-0.09 ± 0.14
0.23 ± 0.23 ± 0.13
0.06 ± 0.21
-0.11 ± 0.18 ± 0.08
-0.02 ± 0.13
-0.56 +-00..2297 ± 0.03
-0.44 ± 0.23
-0.4
-0.2
0.23 ± 0.12 ± 0.07
HEP 2005
HFAG
-0.6
-0.07 ± 0.07
-0.24 ± 0.31 ± 0.15
0.06 ± 0.18 ± 0.03
HEP 2005
HFAG
HFAG
π0 KS
-1.4
0.00 ± 0.23 ± 0.05
-0.14 ± 0.17 ± 0.07
HEP 2005
η′ K0
φ K0
K+ K- K0
HEP 2005
HEP 2005
f0 K S
-1.6
HEP 2005
PRELIMINARY
-0.19 ± 0.39 ± 0.13
HEP 2005
2
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
HFAG
1
ω KS
HEP 2005
HFAG
HEP 2005
0
0.69 ± 0.03
0.50 ± 0.25 +-00..0074
0.44 ± 0.27 ± 0.05
0.47 ± 0.19
0.36 ± 0.13 ± 0.03
0.62 ± 0.12 ± 0.04
0.50 ± 0.09
0.95 +-00..2332 ± 0.10
0.47 ± 0.36 ± 0.08
0.75 ± 0.24
0.35 +-00..3303 ± 0.04
0.22 ± 0.47 ± 0.08
0.31 ± 0.26
0.50 +-00..3348 ± 0.02
0.95 ± 0.53 +-00..1125
0.63 ± 0.30
0.41 ± 0.18 ± 0.07 ± 0.11
0.60 ± 0.18 ± 0.04 +-00..1192
0.51 ± 0.14 +-00..1018
0.63 +-00..2382 ± 0.04
0.58 ± 0.36 ± 0.08
0.61 ± 0.23
KS KS KS
HFAG
HEP
2005
HEP 2005 HEP 2005
HFAG
HFAG
HEP 2005
HFAG HFAG HFAG
ω KS
KS KS KS
Tim Gershon
HFAG
φ K0
f0 K S
η′ K0
π0 KS
K+ K- K0
-1
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
BaBar
Belle
Average
H F AG
Cf = -Af
HEP 2005
PRELIMINARY
BELLE-CONF-0569
b→ccs World Average
H F AG
357 fb−1
sin(2βeff)/sin(2φ1eff)
HFAG
BELLE
0.06 ± 0.11 ± 0.07
0.14 ± 0.10
-0.10 ± 0.25 ± 0.05
-0.50 ± 0.23 ± 0.06
-0.31 ± 0.17
0
0.2
0.4
0.6
0.8
1
1.2
January 24, 2006
BELLE
B 0 → KS π 0γ — Time-Dependent CP Violation
386 fb−1
Time-dependence probes γ polarization
BELLE-CONF-0570
Raw asymmetry/(2.5 ps)
1
0.75
0.5
0.25
0
-0.25
-0.5
-0.75
-1
-7.5
-5
-2.5
0
∆t (ps)
2.5
5
7.5
Invariant mass region: 0.8 GeV/c2 < mK π 0 < 1.8 GeV/c2
S
70 ± 11 signal events
SK π 0γ = +0.08 ± 0.41(stat) ± 0.10(stat)
S
CK π 0γ = −0.12 ± 0.27(stat) ± 0.10(stat)
S
Tim Gershon
University of Oxford Seminar
January 24, 2006
Belle: B → K ∗l+l− — F-B asymmetry
BELLE
386 fb−1
(a) K+ e+e-
(b) K* e+e-
AFB (bkg-sub)
30
1
0.5
20
0
10
+ + -
-0.5
0
(c) K+ µ+µ-
(a) K l l
-1
(d) K* µ+µ-
30
0
2.5
5
7.5
10
12.5
15
17.5
20
2
q
22.5 25
2 2
GeV /c
10
12
14
16
2
q
18
20
2 2
GeV /c
AFB (bkg-sub)
20
10
0
60
1
0.5
(e) K+ l+l-
(f) K* l+l-
0
40
* + -
-0.5
K l l
negative A7
-1
20
0
0
5.2 5.225 5.25 5.275 5.2 5.225 5.25 5.275 5.3
2
Mbc (GeV/c )
Tim Gershon
BELLE-CONF-0521
Events / 2.0 MeV/c
2
Measure Wilson coefficients (A7, A9, A10); find AF B = 0 point
2
4
6
8
A9A10 > 0 excluded at 95% CL
University of Oxford Seminar
January 24, 2006
b → dγ
8
6
4
2
-0.2
0
0.2
0.4
8
6
4
2
0
B → ρ0γ
0
5.2
5.22
5.24
5.26
14
12
10
8
6
4
5.28
0
5.3
-0.4
-0.2
2
∆ E (GeV)
Entries/(50 MeV)
5
0
5
B → ωγ
4
3
2
1
0
-0.4
-0.2
0
0
0.2
0.4
12
10
8
6
4
2
0
5.2
0.2
0.4
0
B → ωγ
3
2
1
5.22
5.24
5.26
5.28
5.24
5.26
5.28
Mbc (GeV/c )
4
0
5.2
5.22
2
∆ E (GeV)
Mbc (GeV/c )
0
B → ρ 0γ
14
2
16
2
2
-0.4
10
Entries/(4 MeV/c )
0
12
-
Entries/(50 MeV)
2
Entries/(4 MeV/c )
10
18
B →ργ
-
5.3
BELLE-CONF-0520
Entries/(50 MeV)
-
357 fb−1
14
B →ργ
-
12
Entries/(4 MeV/c )
BELLE
5.3
2
∆ E (GeV)
Mbc (GeV/c )
Assuming isospin relation:
+0.34 +0.14
B (B → (ρ, ω)γ ) = 1.34−0.31 −0.10 × 10−6
Significance: 5.5σ
+0.038
|Vtd/Vts| = 0.200+0.026
(exp)
−0.025
−0.029 (theo)
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Super B Factory
University of Oxford Seminar
January 24, 2006
Super B Factory
BELLE
• Luminosity frontier probes new physics . . . complementary to energy frontier
• eg. When LHC discovers SUSY, Super B can help identify SUSY breaking
mechanism
• Argument for B physics (& flavour physics) well established
. . . important relation to baryon asymmetry of the Universe
• Complementarity between LHCb and Super B becoming clearer
– Super B only: modes with neutrals, neutrinos, difficult topologies
– LHCb only: modes with Bs , other heavy B hadrons
– Overlap: eg. Bd → π +π −, DK ∗0 to keep us honest
– ATLAS/CMS: very rare modes (eg. Bd,s → µ+µ−)
Tim Gershon
University of Oxford Seminar
January 24, 2006
Fundamental Questions
BELLE
• What: Origin of flavour mixing and CP violation
• Why: Matter dominated universe
• How: Flavour structure in and beyond Standard Model
• Are there new CP violating phases?
b → s TDCPV; UT from tree vs loops; ∆B = 2 & ∆B = 1
• Are there new right-handed currents?
b → sγ TDCPV etc.; B → V V polarization
• Are there new operators enhanced by new physics?
B → K ∗l+l− AF B ; B → Kπ, ππ rates & asymmetries
• Are there new FCNCs? (b,c or τ )
b → sνν̄; τ → µγ etc.; DD̄ mixing, CPV, etc.
Data sample of ∼ 50 ab−1 @ Υ(4S) needed to address these questions
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Super B Factory Parameters
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Super B Factory Upgrade
University of Oxford Seminar
January 24, 2006
BELLE
Crab Cavities
• Head-on collision with finite
crossing angle
• Superconducting crab cavities
under development
• Will be tested in early 2006
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Super B Factory Detector
University of Oxford Seminar
January 24, 2006
BELLE
Super B Factory Detector
• Issues
– Higher background
– Higher event rate
– Special features:
low p µ-ID; hermiticity ⇒ ν reconstruction; KS vertexing
• Possible solutions (nothing is fixed)
– Inner SVD ⇒ striplets
– Inner tracker ⇒ silicon
– Outer tracker ⇒ fast gas
– PID ⇒ “TOP”; RICH; FDIRC . . .
– Endcap calorimeter ⇒ pure CsI
– KLM ⇒ tile scintillator
– Fast trigger & read out; improved DAQ & computing
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Super B Factory Luminosity
University of Oxford Seminar
January 24, 2006
BELLE
Summary
• KEKB is running well, Belle has more and more data to analyze
• Many new and improved results, and more coming soon . . .
• Significant CP V effects appearing in many modes
• Amplitude analyses opening new vistas for B physics
• What I have shown is only a fraction
http://belle.kek.jp/conferences/CONF2005/
• All results shown here are preliminary
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Back Up
Back Up
Tim Gershon
University of Oxford Seminar
January 24, 2006
Υ(5S) Data Taking
BELLE
Ratio, %
Short engineering run has been performed (∼ 2 fb−1 on Υ(5S))
50
N hadron (R2<0.2) / N Bhabha
M = 10868 ± 16 MeV/c
2
Γ = 110 MeV/c
2
(Γ = 105 ± 29 MeV/c )
Const = 35.1 ± 1.9
2
χ = 5.8 / 2
2
48
f(M) = BW + Const
46
44
42
40
38
10.8
10.82
10.84
10.86
10.88
10.9
bwy5sd.f
10.92
10.94
2
M, (GeV/c )
Υ(5S) data taking at high luminosity is possible
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Identifying SUSY Breaking
University of Oxford Seminar
January 24, 2006
BELLE
Tim Gershon
Crab Cavities
University of Oxford Seminar
January 24, 2006
BELLE
Search for Θ(1540)+ Using Kaon Interactions
397 fb−1
BELLE-CONF-0518
8000
6000
4000
2000
0
1.4
1.45
1.5
1.55
1.6
1.65
1.7
Λ(1520) clearly seen in pK −
No signal for Θ(1540)+ in pKS
Tim Gershon
University of Oxford Seminar
January 24, 2006
Not covered
BELLE
• D physics
• τ physics
• ISR physics
• γγ physics
• spectroscopy & exotics
• Rare (& not-so-rare) b → c decays
• Many other rare decays
• b → ulν
• b → clν
• ...
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
CP Violation — Summary
Direct CP violation seen by Belle:
• B 0 → K +π − (∼ 10%
• B 0 → π +π − (∼ 50%
• B + → ρ0K + (∼ 30%
∼ 5σ)
∼ 4σ)
∼ 4σ)
Time-dependent CP violation seen by Belle:
• B 0 → J/ψK 0 (∼ 65% >> 5σ)
• B 0 → π +π − (∼ 65%
• B 0 → η ′K 0 (∼ 60%
Tim Gershon
> 5σ)
∼ 5σ)
University of Oxford Seminar
January 24, 2006
BELLE
B + → D (∗)K + DP Analysis History
• First results shown at Lepton-Photon 2003
– B − → DK − & B − → D∗K −, D∗ → Dπ 0
– 140 fb−1
– Published in PRD 70, 072003 (2004)
• Update with 250 fb−1 at FPCP 2004
– hep-ex/0411049
• First results with B − → DK ∗− at Moriond QCD 2005 / CKM2005
– Not included in combined average yet
– hep-ex/0504013
• Only D → KS π +π − used so far
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
2 ) - Results
Measurement of f (m2
,
m
−
+
Resonance
KS σ1
KS ρ0
KS ω
KS f0(980)
KS σ2
KS f2(1270)
KS f0(1370)
KS ρ0(1450)
K ∗(892)+ π −
K ∗(892)− π +
K ∗(1410)+ π −
K ∗(1410)− π +
K0∗ (1430)+ π −
K0∗ (1430)− π +
K2∗ (1430)+ π −
K2∗ (1430)− π +
K ∗(1680)+ π −
K ∗(1680)− π +
nonresonant
Tim Gershon
Amplitude
1.57 ± 0.10
1.0 (fixed)
0.0310 ± 0.0010
0.394 ± 0.006
0.23 ± 0.03
1.32 ± 0.04
1.25 ± 0.10
0.89 ± 0.07
1.621 ± 0.010
0.154 ± 0.005
0.22 ± 0.04
0.35 ± 0.04
2.15 ± 0.04
0.52 ± 0.04
1.11 ± 0.03
0.23 ± 0.02
2.34 ± 0.26
1.3 ± 0.2
3.8 ± 0.3
Phase (◦)
214 ± 4
0 (fixed)
113.4 ± 1.9
207 ± 3
210 ± 13
348 ± 2
69 ± 8
1±6
131.7 ± 0.5
317.7 ± 1.6
120 ± 14
253 ± 6
348.7 ± 1.1
89 ± 4
320.5 ± 1.8
263 ± 7
110 ± 5
87 ± 11
157 ± 4
University of Oxford Seminar
Fraction
9.8%
21.6%
0.4%
4.9%
0.6%
1.5%
1.1%
0.4%
61.2%
0.55%
0.05%
0.14%
7.4%
0.43%
2.2%
0.09%
0.36%
0.11%
9.7%
January 24, 2006
Systematic Errors
BELLE
Source
Background shape
Background fraction
Efficiency shape
Momentum resolution
Control sample bias
Total
Tim Gershon
B ± → DK ±
∆rB ∆φ3 ∆δB
0.027 5.7◦
4.1◦
0.006 0.2◦
1.0◦
0.012 4.9◦
2.4◦
0.002 0.3◦
0.3◦
0.004 10.2◦ 10.2◦
0.030 12.7◦ 11.3◦
University of Oxford Seminar
B ± → D∗K ±
∆rB ∆φ3 ∆δB
0.014 3.1◦
5.3◦
0.005 0.7◦
1.4◦
0.002 3.5◦
1.0◦
0.002 1.7◦
1.4◦
0.004 9.9◦
9.9◦
0.016 11.1◦ 11.4◦
January 24, 2006
BELLE
Model Uncertainty
iφ(m2+ ,m2−)
2
2
2
2
f (m+ , m− ) = f (m+ , m− ) e
2
2
• Fit to flavour tagged D sample measures f (m+ , m−)
2
BUT φ(m2
+ , m− ) model-dependent
• Estimate model uncertainty by varying model
Fit model
Meson formfactors Fr = FD = 1
Constant BW width Γ(q 2)
Only K ∗, ρ, ω, f0 non-resonant
Total
(∆rB )max
0.01
0.02
0.03
0.04
(∆φ3)max
3.1◦
4.7◦
9.9◦
11◦
(∆δB )max
3.3◦
9.0◦
18.2◦
21◦
• Consider CP -tagged D mesons decaying to KS π +π −
2 ) ± f (m2 , m2 )
→ amplitude is f (m2
,
m
−
−
+
+
• FUTURE: use CP tagged D mesons from cτ factory (ψ ′′ → DD̄)
2 ) ⇒ remove model uncertainty
֒→ measure φ(m2
,
m
−
+
Tim Gershon
University of Oxford Seminar
January 24, 2006
Test Samples
BELLE
B±
→ KS
π+π−
0.15
0.1
0.05
0
→
KS
π+π−
D
D∗
π±
0.2
0.1
0
-
+
B
-
B
-0.1
+
B
-0.1
-0.2
-0.15
-0.15 -0.1 -0.05
0
0.05
0.1
0.15
-0.3
-0.3
-0.2
-0.1
0
Re(r eiθ)
Tim Gershon
π0
0.3
B
-0.05
(rB ∼ 0.01)
Im(r eiθ)
Im(r eiθ)
(r ∼ 0.01)
D
B±
π±
0.1
0.2
0.3
iθ
Re(r e )
3425 events
641 events
rB− = 0.047 ± 0.018
θ− = 193◦ ± 24◦
rB+ = 0.039 ± 0.021
θ− = 240◦ ± 28◦
rB− = 0.086 ± 0.049
θ− = 280◦ ± 30◦
rB+ = 0.015 ± 0.042
θ− = 170◦ ± 186◦
University of Oxford Seminar
BELLE-CONF-0476,BELLE-CONF-0502
253 fb−1
Fit B, B̄ samples separately, float rB ±eiθ± , where θ± = δB ± φ3
January 24, 2006
(∗)
B − → DCP K − — Observables
BELLE
(∗)
(∗)
• Reconstruct D(∗) mesons in CP even (D1 ), CP odd (D2 )
(∗)
and flavour-specific favoured (Dfav ) decay modes
• CP asymmetries
A
A
(∗)
D1 K −
=
(∗)
D1,2K −
(∗) +
(∗) −
+
−
Γ B →D1,2 K −Γ B →D1,2K
= (∗)
(∗)
Γ B − →D1,2 K − +Γ B + →D1,2K +
2rB sin(δB ) sin(φ3 )
1+rB 2 +2rB cos(δB ) cos(φ3 )
A
(∗)
D2 K −
=
−2rB sin(δB ) sin(φ3 )
1+rB 2 −2rB cos(δB ) cos(φ3 )
• Charge averaged rates, normalized to B − → Dπ −
  
 (∗) +
(∗) −
(∗) +
(∗) −
+
−
+
−
Γ B →D1,2 K +Γ B →D1,2 K
Γ B →D1,2 π +Γ B →D1,2 π
 /  
R1,2 =  (∗)
(∗)
(∗)
(∗)
Γ B − →Dfav K − +Γ B + →Dfav K +
Γ B − →Dfav π − +Γ B + →Dfav π +
R1 = 1 + rB 2 + 2rB cos(δB ) cos(φ3)
R2 = 1 + rB 2 − 2rB cos(δB ) cos(φ3)
• Four observables, three unknowns . . .
( rB , δB ) different for B ∓ → DK ∓, B ∓ → D∗K ∓
Tim Gershon
University of Oxford Seminar
January 24, 2006
(∗)
B − → DCP K − — Summary
BELLE
253 fb−1
PRELIMINARY
A1
A2
R1
R2
B ∓ → DK ∓
0.07 ± 0.14(stat) ± 0.06(syst)
−0.11 ± 0.14(stat) ± 0.05(syst)
0.98 ± 0.18(stat) ± 0.10(syst)
1.29 ± 0.16(stat) ± 0.08(syst)
B ∓ → D∗K ∓
−0.27 ± 0.25(stat) ± 0.04(syst)
0.26 ± 0.26(stat) ± 0.03(syst)
1.43 ± 0.28(stat) ± 0.06(syst)
0.94 ± 0.28(stat) ± 0.06(syst)
BELLE-CONF-0443
• Extract CP asymmetries by fitting B − and B + yields separately
∗ K∓ . . .
• First observations of B ∓ → D1,2
∗ K ∓ system
and first measurements of A1,2 in DCP
Tim Gershon
University of Oxford Seminar
January 24, 2006
World Averages
-1
Tim Gershon
0
1.96 ± 0.41
0.65 ± 0.27
2
3
-1.4
Average
-0.27 ± 0.25 ± 0.04
-0.18 ± 0.17
BaBar
Average
BaBar
Belle
Average
University of Oxford Seminar
-0.8
-0.6
-0.4
-0.2
0
0.26 ± 0.26 ± 0.03
0.26 ± 0.26
-0.08 ± 0.19 ± 0.08
LP 2005
Average
-1
0.02 ± 0.12
-0.10 ± 0.23 +-00..0034
Belle
Belle
-1.2
-0.11 ± 0.14 ± 0.05
HFAG
Average
HFAG
D*CP K ACP-
Belle
0.21 ± 0.17 ± 0.07
LP 2005
HFAG
BaBar
LP 2005
HFAG
HFAG
Belle
0.22 ± 0.11
LP 2005
BaBar
0.07 ± 0.14 ± 0.06
LP 2005
DCP K ACP-
0.65 ± 0.26 ± 0.08
1
Average
LP 2005
PRELIMINARY
0.40 ± 0.15 ± 0.08
-0.02 ± 0.33 ± 0.07
-0.06 ± 0.18
-0.26 ± 0.40 ± 0.12
LP 2005
LP 2005
HFAG
Average
1.96 ± 0.40 ± 0.11
Belle
HFAG
BaBar
Average
0.94 ± 0.29
HFAG
Average
1.24 ± 0.20
0.94 ± 0.28 ± 0.06
BaBar
DCP K* ACP-
Belle
1.43 ± 0.28 ± 0.06
LP 2005
Average
HFAG
D*CP K RCP-
Belle
1.06 ± 0.26 +-00..1009
D*CP K ACP+
HFAG
BaBar
1.02 ± 0.12
DCP K* ACP+
Average
1.29 ± 0.16 ± 0.08
LP 2005
Belle
BaBar
0.80 ± 0.14 ± 0.08
LP 2005
BaBar
0.91 ± 0.12
H F AG
ACP Averages
LP 2005
PRELIMINARY
0.98 ± 0.18 ± 0.10
HFAG
DCP K RCP-
Average
DCP K* RCP-
D*CP K RCP+
DCP K* RCP+
HFAG
Belle
H F AG
0.87 ± 0.14 ± 0.06
LP 2005
BaBar
LP 2005
DCP K RCP+
RCP Averages
DCP K ACP+
BELLE
0.19 ± 0.50 ± 0.04
-0.08 ± 0.32
0.2
0.4
0.6
0.8
1
1.2
1.4
January 24, 2006
New
BELLE
B−
→
h
K +π −
i
− Analysis
K
D
PRELIMINARY
• Use 386 million B B̄ pairs
• Use improved continuum suppression
• Other minor changes from PRL 94, 091601 (2005)
Tim Gershon
University of Oxford Seminar
January 24, 2006
New ADS Analysis — B ∓ → Dπ ∓
BELLE
B ∓ → K ∓π ±
D
π∓
B ∓ → K ±π ∓
60
D
π∓
BELLE-CONF-0552
50
4000
Events/10MeV
Events/10MeV
5000
357 fb−1
3000
2000
1000
40
30
20
10
0
−0.20
−0.10
0.00
∆E(GeV)
0.10
0.20
0
−0.20
14518 ± 125 signal events
−0.10
0.00
∆E(GeV)
0.10
0.20
50+11
−10 signal events
−3
RDπ = (3.5 +0.8
(stat)
±
0.3
(syst))
×
10
−0.7
Consistent with previous Belle result
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
B 0 → J/ψK 0 — ∆t Dependence (Poor quality tags)
357 fb−1
B 0 → J/ψKS
B 0 → J/ψKL
Events / ps (poor tags)
q = -1
250
200
150
100
50
-8
-6
-4
-2
0
2
∆t (ps)
4
6
8
1
0.5
0
-0.5
-1
-8
-6
-4
-2
0
2
∆t (ps)
4
6
8
S = +0.668 ± 0.047(stat)
A = −0.021 ± 0.034(stat)
Tim Gershon
500
q = +1
q = -1
400
300
200
100
-8
Raw asymmetry (poor tags)
Raw asymmetry (poor tags)
q = +1
300
-6
-4
-2
0
2
∆t (ps)
4
6
8
-6
-4
-2
0
2
∆t (ps)
4
6
8
1
0.5
BELLE-CONF-0569
Events / ps (poor tags)
350
0
-0.5
-1
-8
S = −0.619 ± 0.069(stat)
A = +0.049 ± 0.039(stat)
University of Oxford Seminar
January 24, 2006
Resolving the sin(2φ1) Ambiguity
BELLE
357 fb−1
• Utilize interference between CP -even & CP -odd final states
eg. B 0 → J/ψK ∗0 → J/ψKS π 0 angular analysis
BELLE-CONF-0546
• New method uses analysis of (eg.) D → KS π +π − Dalitz plot in
B 0 → Dh0 decays (h0 = π 0, η, . . .)
• Similar to B + → DK + analysis for φ3
• Test SM prediction: Sb→cc̄s ≃ Sb→cūd
70
60
50
12
Events/ 10 MeV
80
D∗π 0&D∗η
Dω
Events/ 10 MeV
Dη
Events/ 10 MeV
Events/ 10 MeV
Dπ 0
20
17.5
17.5
10
8
15
6
4
20
2
10
0
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
∆E, GeV
Tim Gershon
0
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
15
12.5
12.5
40
30
20
10
10
7.5
7.5
5
5
2.5
2.5
0
-0.3
-0.2
-0.1
∆E, GeV
University of Oxford Seminar
0
0.1
0.2
0.3
∆E, GeV
0
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
∆E, GeV
January 24, 2006
BELLE
Description of the Method (Pictures)
A. Bondar, T.G., P. Krokovny, PLB 624, 1 (2005)
(Terms of e−|∆t|/τB 0 have been dropped)
ΓB̄ 0 (∆t) ∝ ΓB 0 (∆t) ∝ Tim Gershon
∆m∆t
cos
− iΦ∗
2
∆m∆t
cos
− iΦ
2
Φ∗ = e−i2φ1 ηh0 (−1)l
Φ = e+i2φ1 ηh0 (−1)l
University of Oxford Seminar
2
∆m∆t sin
2
2
∆m∆t sin
2
January 24, 2006
sin(2φ1) — Constraint
BELLE
β/φ1
–
η
HF AG
HEP 2005
PRELIMINARY
=(
1
=(
21.
2
+1. .3)˚
-1
β/φ
0.4
3
68.
0.6
7
0.2
+1
- 1. .3
2 )˚
BELLE-CONF-0546
β/φ 1
0.8
DISFAVOURED BY J/ψK* & Dh0
1
357 fb−1
φ1 = (16 ± 21 ± 11)◦
0
-0.2
-0.2
Tim Gershon
0
0.2
0.4
0.6
0.8
University of Oxford Seminar
1
–
ρ
January 24, 2006
B 0 → ρ+ ρ−
BELLE
BELLE-CONF-0545
Recently, B 0 → ρ+ρ− found tobe powerful for
measurement of φ2 because
• small penguin pollution (B B 0 → ρ0ρ0 < 1.1 × 10−6 (BaBar))
253 fb−1
Initial attempts to extract φ2 have focussed on B 0 → π +π −.
However,
• penguin
pollution
found to be large
• B B 0 → π 0π 0 ≈ 1.5 × 10−6 (HFAG2005)
• large
direct CP violation:
0
+
−
A B →π π
= 0.56 ± 0.12 ± 0.06 (Belle; PRL 95, 101801 (2005))
Isospin analysis possible; large statistical error & ambiguities
• surprisingly (?) little nonresonant contribution
• B 0 → ρ+ρ− almost 100% longitudinally polarized
(almost pure CP state . . . downside is cannot access interference)
Tim Gershon
University of Oxford Seminar
January 24, 2006
B 0 → ρ+ ρ−
Events / 20 MeV
70
60
50
40
30
20
10
5.22
5.24
5.26
0
−0.2
5.28
Mbc (GeV/c2)
Events / (0.089)
Events / (60 MeV)
80
350
300
−0.1
0
-0.4
-0.2
0.1
0.2
0.3
∆E (GeV)
160
140
BELLE-CONF-0545
100
90
80
70
60
50
40
30
20
10
0
253 fb−1
Events / 2 MeV
BELLE
120
250
100
200
80
150
60
100
40
50
0
20
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
Mππ (GeV/c2)
142 ± 13 signal events
Tim Gershon
0
-0.8
-0.6
0
0.2
0.4
0.6
0.8
cos θ
+0.029
flong = 0.951+0.033
−0.039 −0.031
University of Oxford Seminar
January 24, 2006
B 0 → ρ+ρ− — CP Fit
140
120
100
80
60
120
100
80
60
40
20
20
-5
0
0
5
∆t (ps)
Raw Asymmetry / (2.5 ps)
Raw Asymmetry / (2.5 ps)
140
40
0
1
0.75
0.5
0.25
0
-0.25
-5
0
-5
0
5
∆t (ps)
1
0.75
0.5
0.25
0
-0.25
-0.5
-0.75
-0.5
-0.75
-1
-1
-5
0
5
∆t (ps)
S = 0.09 ± 0.41 ± 0.08
Tim Gershon
160
BELLE-CONF-0545
Events / (1.25 ps)
160
253 fb−1
Events / (1.25 ps)
BELLE
5
∆t (ps)
A = 0.00 ± 0.039+0.10
−0.09
University of Oxford Seminar
January 24, 2006
BELLE
Constraint on φ2
253 fb−1
ππ & ρρ
◦
φ2 = 93+12
−11
(cf. φ2 = 87 ± 12◦ from naı̈ve S = − sin(2φ2 ) neglecting penguins)
Tim Gershon
University of Oxford Seminar
BELLE-CONF-0501,BELLE-CONF-0545
ρρ only
φ2 = 87 ± 17◦
January 24, 2006
Description of the Method (Equations)
BELLE
A. Bondar et al., hep-ph/0503174, to appear PLB
• Assume CP T , take ∆Γ = 0, |q/p| = 1, arg(q/p) = 2φ1
• Neglect Cabibbo-suppressed contribution (for now)
• Ignore mixing, CP violation in D system
• Amplitude description (terms of e−|∆t|/2τB 0 dropped)
B̄ 0 (∆t) = B̄ 0 cos(∆m∆t/2) − ie−i2φ1 B 0 sin(∆m∆t/2)
D̃B̄ 0 (∆t) = D0 cos(∆m∆t/2) − ie−i2φ1 ηh0 (−1)l D̄0 sin(∆m∆t/2)
MB̄ 0 (∆t) = f (m2− , m2+ )cos(∆m∆t/2) − ie−i2φ1 ηh0 (−1)l f (m2+ , m2− )sin(∆m∆t/2)
B 0 (∆t) = B 0 cos(∆m∆t/2) − ie+i2φ1 B̄ 0 sin(∆m∆t/2)
D̃B 0 (∆t) = D̄0 cos(∆m∆t/2) − ie+i2φ1 ηh0 (−1)l D0 sin(∆m∆t/2)
MB 0 (∆t) = f (m2+ , m2− )cos(∆m∆t/2) − ie+i2φ1 ηh0 (−1)l f (m2− , m2+ )sin(∆m∆t/2)
ηh0 = CP eigenvalue of h0
Tim Gershon
l = angular momentum
University of Oxford Seminar
January 24, 2006
B 0 → D (∗)h0 Analysis
Data fit results. Statistical errors from toy MC.
Final state
φ1 fit result, ◦
Dπ 0
11 ± 26
Dω, Dη
28 ± 32
D∗π 0,D∗η
25 ± 35
Simultaneous fit
16 ± 21
Raw
i asymmetry.
KS ρ0 h0 candidates.
BELLE-CONF-0546
Ntot Efficiency (%)
Nsig
Purity
265
8.7
157 ± 24 59%
78
4.1
67 ± 10
86%
97
3.9
58 ± 13
60%
52
27 ± 11
52%
492
309 ± 31 63%
357 fb−1
Process
Dπ 0
Dω
Dη
D∗π 0,D∗η
Sum
h
Raw Asymmetry/ 2.5 ps
BELLE
D
1
0.5
0
-0.5
-1
-7.5
-5
-2.5
0
2.5
5
7.5
∆t, ps
Tim Gershon
University of Oxford Seminar
January 24, 2006
B → π +π − Candidates
BELLE
253 fb−1
Categorize candidates based on level of qq̄ background
(a)
Total
+ π π
Kπ
continuum
Three-body
200
150
100
50
0
Tim Gershon
-0.2
0
0.2 0.4
∆E (GeV)
Events/(0.02GeV)
250
Low quality
400
350
300
250
200
150
100
50
0
University of Oxford Seminar
BELLE-CONF-0501
Events/(0.02GeV)
High quality
(b)
-0.2
0
0.2 0.4
∆E (GeV)
January 24, 2006
B → π +π − Analysis
BELLE
253 fb−1
Contributions from tree and penguin amplitudes
penguin contains Vtd
d
W
b
u
b
u
d
d
d
u
W
t
g
d
u
d
BELLE-CONF-0501
tree contains Vub
• Small branching fraction (∼ 4 × 10−6)
• Large background from e+e− → qq̄
(q = u, d, s, c)
• Background from B → K +π −
Tim Gershon
University of Oxford Seminar
January 24, 2006
B → π +π − Fit Result
BELLE
∗ 666 ± 43 π +π − signal events ∗
Sπ +π − = −0.67 ± 0.16 ± 0.06
Aπ +π − = +0.56 ± 0.12 ± 0.06
BELLE-CONF-0501
Total
+ π π
Kπ
continuum
100
0
200
(b) q = -1
Total
+ π π
Kπ
continuum
100
0
Tim Gershon
(a) q = +1
-5
0
Raw Asymmetry Raw Asymmetry
Events/(1.25ps)
Events/(1.25ps)
Plots for high quality events only
200
1
(c) 0.0<r≤0.5
0.5
0
-0.5
-1
1
253 fb−1
∗ 2820 candidates ∗
(d) 0.5<r≤1.0
0.5
0
-0.5
-1
5
∆t (ps)
University of Oxford Seminar
-5
0
5
∆t (ps)
January 24, 2006
253 fb−1
Yields from Mbc—∆E fits in bins of (q, ∆t)
Aππ
B → π +π −
BELLE
1
No. of π+π- events
200
0
tagged as a B
–0
tagged as a B
BELLE-CONF-0501
0.75
0.5
0.25
100
0
-0.25
π+π- asymmetry
0
1
-0.5
1-C.L. at (0,0) = 5.62×10-8
-0.75
1-C.L. at (-0.62,0) = 5.13×10-5
0
-1
-1
-0.75 -0.5 -0.25
0
0.25 0.5 0.75
1
Sππ
-1
-5
0
5
∆t (ps)
• CP violation significance > 5σ (still)
• DIRECT CP V significance : 4σ
Tim Gershon
University of Oxford Seminar
January 24, 2006
BELLE
B → π +π − : Extraction of φ2
253 fb−1
• Such analyses are underway . . .
• Current limitation from knowledge of B 0 → π 0π 0
– branching fraction
– direct CP asymmetry
BELLE-CONF-0501
• Due to large penguin contribution need isospin analysis to extract φ2
• Other avenues for φ2 (ρ±π ∓, ρ±ρ∓, etc.) being explored
Tim Gershon
University of Oxford Seminar
January 24, 2006
B 0 → ρ0 π 0
BELLE
(a)
25
20
15
Events / 2.3 MeV/c2
Events / 20 MeV
30
10
40
(b)
35
30
25
20
BELLE-CONF-05
• Main contributions from ρ±π ∓, other contributions complicate the analysis
357 fb−1
• Dalitz plot analysis of B 0 → π +π −π 0 can measure φ2 & resolve ambiguities
15
10
5
5
0
-0.2
0
0.2
∆E (GeV)
0.4
0
5.24
5.26
5.28
Mbc (GeV/c2)
5.3
Significance: 4.2σ
B B 0 → ρ0 π 0
Tim Gershon
+0.88 +0.60
= 3.12−0.82 −0.76 × 10−6
University of Oxford Seminar
January 24, 2006
B 0 → ρ0 π 0
BELLE
30
Yields / 0.4
40
35
(d)
30
25
20
15
20
10
10
5
0
0.5
1
1.5
0
-1
-0.5
mπ+π− (GeV/c2)
Tim Gershon
BELLE-CONF-05
Yields / 250 MeV/c2
357 fb−1
(c)
50
University of Oxford Seminar
0
ρ
cosθhel
0.5
1
January 24, 2006
A10/A7
0
0
-20
-20
-40
-40
0
20
40
A9/A7
A9/A7 = −15.3 +3.4
−4.8 ± 1.1
A10/A7 = 10.3 +5.2
−3.8 ± 1.8
-40
-20
0
20
BELLE-CONF-0521
20
-20
(b) positive A7
40
20
-40
Tim Gershon
386 fb−1
(a) negative A7
40
A10/A7
Belle: B → K ∗l+l− — F-B asymmetry
BELLE
40
A9/A7
A9/A7 = −16.3 +3.7
−5.7 ± 1.4
A10/A7 = 11.1 +6.0
−3.9 ± 2.4
University of Oxford Seminar
January 24, 2006