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3# Constraints from the CKM fit |V ub |, |V cb |, K, m d, m s At 95% C.L. Unitarity Tests : Search for deviation from SM Using direct measurements of angles check: + + Check if B Decays are consistent with the range of angles from the CKM fit? Indirect info on angles oe A. Hoecker et al, Eur. Phys. Jour. C21 (2001) 225, [hep-ph/ ]
Citation preview
1#
CKM Unitarity anglesand
Recent results from the B factories.)
Hassan JawaheryUniv. of Maryland
Lepton-Photon SymposiumFermi National Accelerator Laboratory
August 12, 2003
Outline• Introduction & definitions • Experimental observables related to and • Experimental results, some discussion of
implications for SM & constraints on and
2#
| |V Vc d c b
V tdV ub*
*
*td tb
cd cb
V VV V
*
*ud ub
cd cb
V VV V
0VVVVVV *tbtd
*cbcd
*ubud
112/1
2/1
23
22
32
AiAA
iAVCKM
The Unitarity Test
CPDefinitions
)arg(
)arg(
)arg(
*
*
*
*
*
*
cdcb
cdub
tdtb
cdcb
udub
tdtb
VVVV
VVVV
VVVV
Both involve Vub
3#
Constraints from the CKM fit |Vub|, |Vcb|, K, md , ms
oo
o
o
o
o
8037
12277
5.264.19
At 95% C.L.
Unitarity Tests : Search for deviation from SM
Using direct measurements of angles check: ++
Check if B Decays are consistent with the range of angles from the CKM fit?
Indirect info on angles
A. Hoeoecker et al, Eur. Phys. Jour.
C21 (2001) 225, [hep-ph/0104062]
4#
b uu
sd ,
W
a1….
Tree diagrams are not alone:
b uu
sd ,
W
..
CKM suppressed
Penguins (gluonic & E.W) can also lead to the same decays:
W
tb sd ,
u
u
g
Main source of info on and Decays involving bu transitions
Data indicate gluonic penguins are large & complicate extraction of
I- Charmless B Decays
Interference of T & P results in Direct CP violation & sensitivity to
d
s
5#
b uW
sc
+
KDB 0
KDB 0
B- DCPK-
II- Decays involving interference of bu W- & bc W- Processes
(Penguin Free)
bW
s
cu
Involves arg(Vub)=
BDK:
dependence of rate and direct asymmetry
B0D
c0B
d
bu
d
*D
d
bc
d 0B
u
*D
0B
d+
Direct CP asymmetry sensitive to sin(2
arg(Vub)=
Same final state via B0 mixing & bu
6#
Experimental Observables
With Tree and Penguins both in action:
γδ |TP
|cpA
|TP
|γδ | TP
|Br
)iδ|P|eiγ(|T|eA)iδ|P|eiγ(|T|eA
sinsin2
2coscos21
To constrain requires estimates of:
| P/T|& relative strong phase
Branching fractions for various non-charm B decays
Time Integrated (Direct) CP asymmerties
)fΒΓf)ΒΓf)ΒΓ)fΒΓAcp
7#
More observables: Time – Dependent CP Asymmetries
2sin(&02**
**
SCeVVVVVVVV i
udubtdtb
udubtdtb
With Tree alone
2
2
11
||||
fC21
2||)Im(
fS
Time evolution of tagged B0 decays, e.g. in the case of B0
)]tmcos(C)tmsin(S1[4e)t(f dfdf
)/t(
CPV due to mixing and decay interference
Direct CPV in Decay )()(
pq
0
0
fBAfBA
iγeiδe|TP|1
iγeiδe|TP|1
2ieλ
With Penguin and TreeS=sin2eff
eff –
C 0
Belle: Af = - Cf (BaBar)
8#
A few comments on the already established pattern from charmless 2-body decays
Connected via Isospin symmetry (Gronau &London) (Isospin engineering)
00 ππππ~ BABA
ππ~2
1 0BA
ππ2
1 0BA
000 ππBA
000 ππ~BAππ
With Tree alone,expect:
%5
KB
4
KB
Measurements:
Penguins are significant players
P’ & use SU(3)connections to estimate P
(P’ & T’)
(P’)
(P & T)(P & T)
(T)
(P’ & T’)(P’ & T’)
Control rescattering effects
Constructing these triangles is a major goal of the experiments
9#
Goals and Issues on the Measurement Side
The reality (Considering the presences of large Penguin effects)
No single measurement is expected to lead to determination of &
Need info from many decay modes and the emerging pattern & connections via symmetries, [isospin, SU(3) ], and eventually more predictive theories [perhaps QCD factorization or perturbative QCD- when verified ] to constrain various components of the problem.
Search for CP violation: Direct (C 0) & Indirect (S0) deviating from (sin2ie. indirect CPV outside of mixing phase.]Measure/Constrain using many different modes and exploit the redundancy to resolve the ambiguities.
Keep finding the pieces of the charmless puzzle
The job description Eventually
10#
Experiments and Data Asymmetric e+e- B Factories:Physics coverage : Bd & Bu Decays
BaBar at SLAC PEP-II Machine 113 fb-1 on s) ( 126 fb-1 total)124x106 B B events
Belle at KEK-B Machine140 fb-1 on s) (158 fb-1 total)152x106 B B events
CLEO at the CESR Machine – Some results on Br & direct Asymmetries.The pioneer of the field and the first source of information on B decays,Including observation of charmless decays. [~13 fb-1 on peak]
The B physics reach of hadron machines & current status covered by Kevin Pitts . Next Talk
The focus of this talk
11#
Analysis Issues for Rare B Charmless decays
-Looking for modes with Br~10-6 to 10-5 -Continuum qq(bar) background at 103 larger than the signal BKG Suppression using event shape & topology, kinematics, particle ID,..
Kinematic variables:
E=Ebeam-EB
provides separation of KK,
K, decays
22Bbeam pEMes
Signal Monte Carlo
Other info into analysis:
t=z/<c
Flavor tag of other side
Particle ID, event shape,..
12#
The road to Measurement of CPV in B
K
BaBar: 81 fb-1 Belle 78 fb-1
K
Isolation of Signals
B
Per experiment
K
13#
Time Dependent CPV in B
(BaBar)
Asy
mm
etry
E
vent
s/1p
s
(Belle)
5-5 0
5-5 0
B0 tag
B0 tag
Fits to: )]tmcos(C)tmsin(S1[4e)t(f dfdf
)/t(
81 fb-1 78 fb-1
04.025.030.005.034.002.0
CS
)(08.027.077.041.023.1 08.0
07.0
ACS
t(ps) t(ps)
14#
New Results:BaBar Update of CPV measurements with full data sample (Run 1+2+3): 113 fb-1 on Peak data
013.0041.0107.005.019.019.003.022.040.0
KACS
4.105.125.373.8730.249.265
KK
K
NNN
Reprocessed Run1+2 (82 fb-1 )
Added Run 3 ((31 fb-1 )
New CPV Results
Run1+2(reprocessed)
S=-0.252±0.27 C=-0.166 ±0.22
Run 3
S=-0.67±0.35 C=-0.33 ±0.34
B0 tag
B0 tag
15#
Summary of CPV in B
Current world average (with BaBar new results)
S=-0.58±0.20 C=-0.38 ±0.16
Too early to claim observation of CPV in B Direct (in decay) or Indirect(mixing &
decay)
Belle’s update with their full data set awaited
S & C not enough to measure
Need eff – , which requires the other pieces of the isospin analysis.
)effα2sin(2C1S&0C
gnoring the large ~2 )
16#
BaBar: The decay B
21431346)(
N 60 103.06.01.2)( BB
Significance: 4.2
Used their full data set (113 fb-1 )
Measured Br(BBr(Bx10-6 ]
Control over a major background source. Br about half of previous assumed value
qq bkgd
Fischer Discriminant
signal
Observation
17#
Belle: The decay B
3.94.86.25)(
N
Analyzed full data set of 140 fb-1
From a fit to 2-dimensional distribution of Mes and E
Find:
Significance:3.4
60 103.06.07.1)( BB
Evidence
18#
Branching ratios (x10-6) Mode CLEO Belle BaBar Average
4.5 4.4 0.6 0.3 4.7 0.6 0.2 4.6 0.4
4.6 5.3 1.3 0.5 5.5 0.6 5.2 0.8
<4.4 1.7±0.6 ±0.3 2.1 ±0.6 ±0.3 1.97 ±0.47
4121.. 50
40..
8161.. 70
60.. 01
90..
What about All but one piece is in place
For a full Isospin analysis need: Cdirect CPV)
&
Still some constraint can be set using the measured average Branching fraction:
)B(B 000 )BB( 000
(Quinn- Grossman),
With WA Br(B
eff | at 90% c.l.
00 ππππ~ BABA
ππ~2
1 0BA
ππ2
1 0BA
000 ππBA
000 ππ~BAππ
Not a very useful limit & don’t expect more than ~10o improvement in future.
0
0002
((sin
BBBB
19#
Summary of measurements of BDecaysSee John Fry’s talk this morning for more detail &comparison with Theory
Thanks to Heavy flavor averaging group(HFAG): Rare decays: J. Smith (colorado), J. Alexander(Cornell), P.Chang (KEK)
03.009.0)(02.016.004.0
)(012.0041.0107.0)(014.0035.0086.0
AverageCLEO
BaBarBelleAK
Evidence Direct CPV ?
20#
What did we learn about
s this all consistent with
Standard Model?
Does it accommodate the range of UT angles from the global CKM fit?
21#
C vs S:
Allowed range & comparison with SM ( CKM fit)
Data consistent with SM (CKM fit)
Gronau and Rosner approach(PRD 093012)|P / T | estimated usingB->K0+ & Bl , B 0+
(with use of SU(3) & factorization)
Here calculate S & C for |P/T|~0.3Unconstrained strong phase
iγeiδe|TP|1
iγeiδe|TP|1
2ieλ
212
||)Im(
fS
2
2
11
||||
fC
BaBar
Physical boundary
Belle
BaBar
My Average
22#
A more optimal use of information using the CKMfitter tools with various assumptions (LAL 02-103: Authors Hoecker, Lacker, Pivak, Roos).
In all scenarios data can accommodate the range of from the SM CKM fit
SU(3) & some use of QCD Factorization to estimate SU(3) breaking effects
23#
Useful ratios of branching fractions and ps-asymmetries with sensitivity to
)()()()(
000000
00
0 21
KBBrKBBrKBBrKBBr
AR
nn
)()()()(
00
00
0
2KBBrKBBrKBBrKBBr
AR
cc
sinsin2
)cos21(cos)(cos21
,,,
0
2,
2,,,
ncncnc
ncncncnc
rA
rqqqrR
000
00
0 B
B
tt
KBBrKBBrKBBrKBBr
AR
)()()()(
Constraints on Connecting the BK data via symmetries
Ratios using HFAG averages:
R0=0.99±0.09 A0= - 0.09 ±0.03
Rc=1.30±0.15 Ac=0.0 ± 0.06
Rn=0.8 ±0.11 An=-0.07 ± 0.03
Rosner, Gronau, Neubert, Fleischer, Mannel, ..
All shown to accommodate range of from CKM fit(Fleischer), (Gronau, Rosner),…
Size of EW penguins|T/P|
24#
1 range of R0
60 < at 1 level
No useful limit at 2 level
Consistent with CKM range: oo 8037
R0
A0=-0.06(A0+1
A0=-0.12(A0-1
Gronau & Rosner method hep/ph-0307095
(R0 vs for fixed A0
R0
25#
Other channels of reaching BCPV studies require isolation of states with specific CP parity: e.g. B ( using Dalitz plot analysis.Interference between (can be used to determine even in the presence of penguins [Quinn-Snyder]
BaBar has presented CPV results based on quasi 2-body decays B0”“B0””updated for this conference with their full data sample.
1st Belle results on CPV with these modes expected soon.Components of the Isospin analysis (pentagon) are also being measured. (J. Fry’s talk today)
B( e.g. Bhas been measured and shown to be dominated by the CP even component – good news for CPV studies.
26#
CPV Studies with the decay B0
Not a CP eigenstate & involves more observables:
Summing over the charge:
Direct CP violation: C
Indirect CP (mixing and decay): S
Charge Asymmetry:
)cos()()sin()(1())(1()(
)cos()()sin()(1())(1()(/||
/||
0
0
tmCCtmSSehAtf
tmCCtmSSehAtf
hhhht
CPh
B
hhhht
CPh
B
)()()()(
hNhNhNhNA h
CP
Dilution (Non CP parameters): C & S
)cos()sin()/( tmCtmSBBA
00
27#
BaBar results on CPV in B: 113 fb-1
N() N() C C S S ACP() ACP()804.2 49.2
260.4 31.4 0.35 0.13
0.20 0.13
-0.130.18
0.33 0.18
-0.110.06
0.18 0.12
)cos()sin()/( tmCtmSBBA
00
28#
2.5 (2.7 if stat. only)
99%
90%98.6%
Define two asymmetries:
CACCACABNBNA
CACCACABNBNA
CP
CPCP
CP
CPCP
1)()(
1)()(
00
00
05.018.0 ,07.052.013.013.0
19.017.0
AA
New Results
04.011.0 ,06.062.017.016.0
28.024.0
AAPRL
2.3 (Stat. only)
Test Of Direct CPV
29#
Quinn-Grossman bound applied to the longitudenal polarization component of the rates:
oeff
LLeff lcBfBf
19||
...%[email protected])/()(sin 2
The Channel to watch in Future
The components of Bare identifeid: B0(BaBar),B+elle & BaBar)
Decays nealy 100% longitudinally polarized [CP-even]
Limit has been set on B0See John Fry’s talk this morning for more detail
>2 times more restrictive than Bsystem
A promising channel:the B system
30#
Reaching
via
(bu(cs) & bc(us) interference:
BDK DecaysMethod and observables suggested by Gronau, Wyler,Atwood,Dunietz, Soni,Quinn, Sanda
31#
BDK Modes- No penguins
b uW
sc
)( *uscbVV
ii eeAKDBA 2||)( 10
bW
s
cu
12
0 ieAKDBA ||)(
)( *uscbVV
In B- DCPK- , the diagrams interfere & provide the sensitivity to :[DCP=(1/2)(D0 D0 ) ] KKD evenCP , ,.., ssoddCP KKD 0
)()()()(
KDBBKDBBKDBBKDBB
R cpcpcp 00
00
)()()()(
KDBBKDBBKDBBKDBB
Acpcp
cpcpcp 00
00
coscos DKDKDK rr 21 2
coscos
sinsin
DKDKDK
DKDK
rrr
2122
rDK (~0.1 –0.2) & DK
Also unknown
Experimenters are very active in constructing the DK puzzle
Observables
DK triangle
32#
coshel
from P→PV
MK*-
D0 → K, K,K 0
B-→DCP K*-
13.14.34.3
D1=K+K-, +
D2=Ks, Ks, Ks
7.23.6 2.4
B- → D*0 K*-
B → D*0 K*- ALL
D*0 → D0 0 D*0 → D0
B0 → D K0
33#
R1(CP=+1) A1 (CP=+1) R2(CP=-1) A2 (CP=-1)
BaBar 1.06 ±0.26 ±0.17 0.17 ±0.23 ±0.08
Belle 1.21 ±0.25 ±0.14 0.06 ±0.19 ±0.04 1.41 ±0.27 ±0.15 -0.19 ±0.17 ±0.05
Average
BDoK-
Br(x10-4) R1(CP=+1) A1 (CP=+1) R2(CP=-1) A2 (CP=-1)
BaBar 6.3 ±0.7 ±0.4
Belle 5.2 ±0.5 ±0.6 -0.06 ±0.33 ±0.07 0.19 ±0.50 ±0.04
CLEO 6.1 ±1.6 ±1.7
Average
BDoK*-
)KDB( **0B (8.3 ± 1.1(stat) ± 1.0(sys)) x 10-4 & L/0.86 ±0.06 ±0.03 (BaBar)
(7.7 ± 2.2(stat) ± 2.6(sys)) x 10-4 CLEO
Mode Br(x10-5)Belle
Br(x10-5)BaBar
Br(x10-5)Average
B0DoK*0 4.8 ±1.1 ±0.5 3.0 ±1.3 ±0.6
B0DoK0 5.0 ±1.3 ±0.6 3.4 ±1.3 ±0.6
B0D*oK0 <6.6 (90% c.l.)
B0D*oK*0 <6.9 (90% c.l.)
B0DoK*0 <1.8 (90% c.l.)
B0D*oK*0 <4.0 (90% c.l.)
The BDK puzzle under construction
Vub
Vub
34#
What about Current errors are still too large to allow for simultaneous extraction of ratio of (bc) and (bu) amplitudes (rdk) and the strong phase. Need many fold more data. (may be possible with 500 fb-1)
With assumptions on (rdk): mild limits can be extracted. e.g M. Gronau (hep-ph/0306308): at 1 sigma level.
35#
Reaching sin(2
via
(bu(cd) & bc(ud) interference
(& B0 mixing)
B0D(*+) - Method and observables first suggested by Sachs,Dunietz
36#
B0D(*+)- Modes
c0B
d
bu
d
*D
Dominant diagram b c transition
d
bc
d 0B
u
*D Suppressed diagram b u transition
0B
b
d
*||)( udcbi VVeADBA 2
10 i
ubcdi eVVeADBA ||||)( *
20 2
)}sin()cos(1{),(
)}sin()cos(1{),(|0
|0
tmStmCNetDBP
tmStmCNetDBP
ddt
ddt
Time evolution:
2sin(1
22r
rS2
2
11
1rCr
02.0)()(
0
0
DBADBAr Small asymmetry expected
37#
BaBar
II - Fully reconstructed
B0D(*+)- Decays
Lepton tags kaons tags
0 0
0 0
tag tag
tag tag
B BCP
B B
N N
N N
A
Belle Fully reconstructed B0D(*+)- Decays
lDrlDrlDrlDr
DD
DD
DD
DD
*(036.0013.0056.0022.0)2sin(2*(036.0013.0059.0094.0)2sin(2*(036.0016.0056.0033.0)2sin(2*(036.0016.0059.0092.0)2sin(2
**
**
**
I- Partially reconstructed B0D*+- Decays: (number of events)
035.0068.0025.0sin)2cos(2021.0038.0022.0cos)2sin(2035.0070.0031.0sin)2cos(2021.0038.0068.0cos)2sin(2
**
**
DD
DD
DD
DD
rrrr
017.0025.0064.0cos)2sin(2 ** DDr
2
38#
(*)
(*)
0 (*)
(*) 0 (*)
( )( )
S
s cd D
cs D
fBr B D VrBr B D V f
Use measurements of B0D(*+)sto
estimate r(*) (Factorization & SU3 correction )
0.004 * 0.0050.005 0.007( ) 0.021 ( ) 0.017r D r D
sin(2 ) 0.89 @ 68.3% C.L.
sin(2 ) 0.76 @ 90% C.L.
Interpretation:BaBar’s attempt
Favors the CKM favored solution to sin
39#
Summary & Conclusions Major progress made in probing the charmless sector of B decays for
information on unitarity angles New updated measurements of CPV in B still show no
significant evidence for CP violation in this mode.
Observation of B – a missing component of Tree/Penguin disentanglement plan. CPV studies in Bshows hints of direct CP violation. The decay is now measured and looks promising for CPV
studies and constraining . Indications that penguins are smaller. Indication of direct CPV in BWA: Belle, BaBar, CLEO) No indication for large direct CP yet. The emerging constraints on the angles from the pattern of data are
consistent with the favored range from the CKM picture in the Standard Model.
Penguin free modes (BDK & D* are beginning to contribute to constraints on CKM parameters & many new BDK modes identified.
Much more data & major progress in theoretical understanding of hadronic B decays needed to complete the picture and conclusively perform the CKM unitarity test.