Results from BELLE and BaBar

1
Results from BELLE and BaBar
KEK ?????

• Experiments/Tools

• B-Physics

• Selected topics of new Results

2
Asymmetric Energy ee- Collider
600
340
3
Detectors
4
Procedure to extract B Signal
Use special Kinematics of Y(4S)
Two nearly independent variables MB and DE can be
used to select B meson signal

MB (Ebeam)2 (S Pi)2
DE SEi - Ebeam

Methods to extract B signal yield 1) Cut on MB
and fit to DE 2) Cut on DE and fit to MB 3)
Double dimensional fit to MB and DE
distribution 4) If B-gtP1P2P3 cut DE and MB box
and look at resonant structures in M(P1P2) mass
distribution.
5
Continuum Suppression
Dominant Background for rare Decays
Continuum
ee- ? qq continuum (3x
BB)
Jet-like
To suppress use event shape variables
BB
spherical
6
Continuum Suppression

• To separate spherical BB events from jet-like
  continuum events, topological variables are
  used
• Second Fox-Wolfram moment
• Super Fox-Wolfram
• (six modified Fox-Wolfram moments, Fisher
  discriminant)
• 3) Angle between B meson and
• beam axis direction
• 4) Angle between thrusts of
• selected B meson particles and all other
  particles in event
• Likelihood ratio includes all info.

7
Unitarity Triangle
i1,k3 VubVudVcbVcdVtbVtd 0
CKM-Matrix
VubVud VcbVcd
VtbVtd VcbVcd
1
0
?
-(r?ih)
-(1-r?ih)
Self-consistent if SM is correct!!
r?ih
Unitarity Triangle
r?ih
VtbVtd VcbVcd
f2
VubVud VcbVcd
(a)
f1
f3
1
(g)
(b)
0
8
Time-Dependent CP Asymmetry

• The CP violation manifests itself in proper-time
  difference distributions of two B meson decays.

• The time-dependent CP asymmetry ACP is

• Standard Model prediction S(ccs) sin2f1,
  A(ccs) 0 S(sss) sin2f1, A(sss) small

9
Principle of Measurement
BCP
e- 8.0 GeV e 3.5 GeV
e-
e
fCP (J/yK0)
?(4S)
bg 0.425
Btag
Dz ? cbgtB 200 m m

Flavor tag
Dz

• Reconstruct B ? J/yK0 Decays
• proper-time difference Dt
• Get flavor from Btag
• Calculate CP Asymmetry from both Dt Distributions

10
Reference Pointprecision sin2b
0.685 0.032
386x106 BB
227x106 BB
BaBar 2004
Belle 2005
background
11
2005 results Bkg subtracted B?? ?- projections
sin2a sin2F2
B0 tagged
B0 tagged
pp- Yield
4s signal for Direct CPV
pp- ACP
DE-Mbc 2D fits to individual time intervals
Dt (ps)

12
2005 Status of B?? ?-
Belle 275M
Spp
BABAR 227M
2.3s difference between Belle and BABAR
- App (Cpp )
13
Belles measurement of ACP(B??0 ?0 )
Chao, Chang et al, PRL 94 181803
275M BBbar pairs
14
Measuring a in B ? rr
Best mode for a
100 longitudinally polarized
fL 100 ? CP 1

• quasi-two-body approx Ok

• no rpp ? ignore interference

• null search for r0r0

B(r0r0) ltlt B(rr?), B(rr0) lt 1.1
30 ? 6 (26 ? 6 ) x 10-6
New measurement of rr0
230 M(BB)
15
CPV in B???-
Somov, Schwartz et al hep-ex/0601024
(274 ? 106 BB pairs)
Measuring F2
q1
q-1
sin2F2
Results
Low quality tag
High quality tag
No CPV?F2 is near 900
16
Constraints on ?2 (a)
B??? PRL95,101801(2005) ?? combined
?
?
?
Fit
at 90 CL
17
Measuring g(f3) in B ? DK
In general need 2 amplitudes with different
weak and strong phases leading to the same final
state
Relative amplitude rB, weak phase g and strong
phase dB
Critical parameter

• Use additional dof in D decay to determine
  simultaneously rB, g, dB
• Three methods on the market
• GLW, ADS, D0 Dalitz(GGSZ)

18
Belle method for f3 Dalitz
Poluektov et al hep-ex/0604054 (subm. PRD)
3) fCOM D0 ? KSpp-
f353.3 -17.7
14.8
A2 A1
B
r
Obtain from tagged D0 (D? D0p) Continuum sample
WA CKM-Fitter
B-
g59.8 -7.9
13.9
B-
CPV Asymmetry in Dalitz dist.
mm(Ksp), m-m(Ksp-)
19
New Results for the GLW Method (D ? fCP)
hep-ex/0512067
232 M(BB)
4 observables (ACP-,RCP-) to determine rB, g, dB
131 CP

• Theoretically clean
• B ? Dp background
• Limited statistics

148 CP-
New from BaBar D0 ? KSw, KSf
20
Measuring sin(2bg) in B ? D()p, Dr
Same idea interference between b ? c and b ? u
But now D flavor known, B flavor unknown?mixing
Vcd
Suppressed
Vud
Interference
Vub
Favored
Vcb
u,c,t
u,c,t
Time-Dependent CPV Analysis
Large rate for favored decay, but
small CP asymmetry!
21
Other Measurements Related to b

• sin2b in B ?J/yp0(b?ccd)
• Color-suppressed tree gives sin2b (no penguin)
• b ? d penguin pollution (small unless NP)
• cos2b in B ?J/y K(?KSp0)
• Time-dependent angular analysis
• Itoh et al PRL 95(2005)091601
• cos2f1

hep-ex/0603012
0.870.740.12 gt 0.
22
CP angles only
cos2b gt0.
Ambiguity removed by i.e.Dalitz analysis of
B0?D0(Kspp-)h0 Krokovny etal hep-ex/0605023(subm
PRL) or B0?J/yK(?Ksp0)
f170o

Disfavored gt2s

f170o
sin2f1
2-fold ambiguity 2f1 ? p-2f1
f120o
f120o
f1
23
sin2beff in b ? (qqs) Penguins
Searching for New Physics in the loop (2 examples)
Look in B0 ? (be creative)K0
(r)
and hope Dsin2b ? 0
B0?r Ks
sin 2b 0.170.52 0.26
First Measurement!
B0?FK0
24
Summary of sin(2b) in Penguins
Results
Representative theory estimates
gtgtall systematically below sin(2b) gtgtQCD
corrections sin2b(penguin)gtsin2b(tree)
Naïve2 Average 0.50 0.06 (2.8s)
sin2f1(penguin)-sin2f1(tree)
25
How about the CKM triangles sides?
Dmd b ? d g

Vud Vub
?2(a)
b ? u l-n B-? l-n
Vtd Vtb

?1(b)
?3(g)

Vcd Vcb
b ? c l n
26
Belle Inclusive Vub

• Electron energy
• at endpoint
• Pth 1.9 GeV/c
• Systematic limited

Limosani et al PLB 621, 28

• Hadronic and leptonic
• invariant mass (Mx, q2)
• Use full recon tag.
• P also measured.

Bizjak et al PRL 95, 141801

• Non-experimental error dominated by errors of
  shape function parameters.

PDG 2002 (3.6 ? 0.7) x 10-3
27
Inclusive Vub Summary
Vub4.45/-0.20/-0.26 x 10-3
DVub _at_7.5!
28
First Observation of b?d ?
Mohapatra. Nakao, Nishida et al hep-ex/0506079
CDF
CDF
_
Addresses the same physics issue as Bs- Bs mixing
29
Additional Constraints for Unitary Triangle
?
?
?
?
30
Current status
Constraints from Loop
Constraints from tree
CPV angles only ?0.3210.027 ?0.1930.57
sides only
?0.3420.02
?0.2160.06
31
FB asymmetry in B?K()ll-
New physics in EW penguins?
2005, L357fb-1
?Bl-
B
-
l l
3.4 s from 0
K()
11413 ev.
?Bl-
Interference between vector O7 (electromagnetic)O
9(semileptonic) and axialvector O10(semileptonic)
operators
Wilson coefficients
32

• Pure leptonic decay

2.050.65-0.55(stat)
Ikado et al hep-ex/0604018
4.0 s
33
10.75
0.245
34
New Ds ? mn and fDs
Single best measurement of decay constant!

• Helicity-suppressed leptonic decay
• directly related to decay constant fDs
• feeds interpretation of B, Bs mixing
• Analysis Method D reco in ee- ? cc

D reco side
Signal peak in
(normalize to Ds ? fp)
BaBar (230fb-1)
Lattice QCD
BaBar
35
Finds lots of new mesons some puzzles
Choi et al, PRL 89 112001
Z(3931) cc2?
Choi et al , PRL 91 262001
hc
X(3872)
Uehara et al , PRL 96 082003
Y(3940)?wJ/y
ee-?cccc
Choi et al , PRL 94 182002
??
Pakhlov et al , hep-ex/0507019
M(wJ/y) MeV
36
More Studies of DsJ(2317) and DsJ(2460)
Hep-ex/0605035
First measurement of absolute BFs
Look for resonance structure in B recoil
Combine with previous measurements of partial
rates to obtain absolute BFs
0.70 - 0.15 (wheres the rest?)
37
New baryons
?c0(2800), ?c(2800), ?c(2800) observed in ?c?
mass spectra
Mizuk et al PRL 94,122002(2005)
Background subtracted spectra
Feed-down from ?c(2880) ??c?
Feed-down from ?c(2880)?? c?
2005, L281fb-1
Tentative identification admixture of ?c2 ?c1
JP3/2-
38
A New Charm Baryon ?c(2940)
288fb-1
Run5!
Observed in ee- ? cc, Lc(2940) ? D0p
hep-ex/ 0603052
?c(2880)
First observation of ?c(2940)
?c(2940)
First observation of ?c(2880) ? D0p
sidebands
39
New baryons
?cx(3077)
2006, L462 fb-1
Initial motivation checking SELEX
?cc(3519)??cK- ?
No ?cc signal observed But Two new excited
charm strange baryons found
?cx(2980)
wrong-sign ?cK?-
Preliminary
Both ?cx? ?c K ? are not identified yet New
decays mechanism of charmed baryons c and s
quarks are carried away by different final state
particles
40
Summary
f3 error ?100 ??
B?tn
cc2
X(3940), Y(3940)
b?d penguins (b?dg B?KK)
DD-mixing (worlds best limit)
f2 error?100
Vub error lt?10
Sc baryon triplet
Direct CPV in B?Kp-
X(3872)
B?Kll- EW penguin
D00 D10 mesons
CPV in B decays
hc ee-?cccc
41
Summary
Both experiments show that the CKM-ansatz works
extremely well for tree processes
Verified with high precision an anchor point
for NP
CP-Violation in penguins is a sensitive probe for
NP
Experimentally and theoretically clean Measuring
penguin Bf down to 10-6 with high precision
Pure leptonic decays B? t n and Ds? m n
Unexpected discoveries New mesons and baryons
Expect more in the future
42
Spares
43
ACP(B0 ? Kp-)
_ B0? K-p
B0? Kp-
Signal 2139 ?53
submitted to PRL
ACP -0.101 ? 0.025 ? 0.005
3.9s significance
PID efficiency bias correction dA -0.01 ?
0.004
Evidenz for DCPV Belle A(pp-) 3.2s