Download - CP Violation and CKM Angles Status and Prospects Klaus Honscheid Ohio State University C2CR 2007
CP Violation and CKM Angles Status and Prospects
Klaus HonscheidOhio State University
C2CR 2007
K. Honscheid, Ohio State University, C2CR 2007
PEP-II at SLAC
KEKB at KEK
Belle
BaBar
9 GeV (e) 3.1 GeV (e+)peak luminosity:
1.21034cm2s1
Two asymmetric-energy B factories
8 GeV (e) 3.5 GeV (e+) peak luminosity:
1.71034cm2s111 nations, 77 institutes, ~600 persons
13 countries, 57 institutes, ~400 collaborators
The Two Asymmetric Energy B Factories
K. Honscheid, Ohio State University, C2CR 2007
Experimental Landscape (early 2007)
0
200
400
600
800
1000
1200
1990 1992 1994 1996 1998 2000 2002 2004 2006
Tota
l In
tegra
ted L
um
inosi
ty (
fb-1)
CLEO IICLEO II.5
BaBar
Belle
710 fb-1
400 fb-1
Tevatron > 2.4 fb-1
# of B decays recorded
1.3 Billion
0.8 Billion
K. Honscheid, Ohio State University, C2CR 2007
CP( ) =
CP Violation in the Standard Model
CP Operator:
q
q’
J
g
q
q’
J
g*
Mirror
coupling
To incorporate CP violation
g ≠ g*
(coupling has to be complex)
K. Honscheid, Ohio State University, C2CR 2007
CP Violation in the SM: The CKM Matrix
The CKM matrix Vij is unitary with 4 independent fundamental parameters
Unitarity constraint from 1st and 3rd columns: i V*
i3Vi1=0
β
-i
-i
γ1 1
1 1 1
1 1
e
e
CKM phases (in Wolfenstein convention)
u
d
t
c
bs
Vud Vus Vub
Vcd Vcs Vcb
Vtd Vts Vtb
arg[Vub*]arg[Vtd*]
112
11
2
11
23
22
32
AiA
A
iA
K. Honscheid, Ohio State University, C2CR 2007
Interfering Amplitudes in Bo KDecays
B0 -+
B0 +-
A1 = a1 ei1 ei1
A1 = a1 e-i1 ei1
Asymmetry = = ~ 2 sin() sin(2)= 0
A2 = a2 ei2 ei2
A2 = a2 e-i2 ei2
+
+
|A|2 – |A|2
|A|2 + |A|2
(B) – (B)(B) + (B)
s
u
dd0B
KubV
*usV
b u
Tree decay
ubusVVA *
s
u
dd
0BKg
b
utcu ,,
Penguin decay
tbtsVVA *
Interference(A1+A2)2≠ (A1+A2)2
K. Honscheid, Ohio State University, C2CR 2007
227 x 106 B0 Mesons
Count B0K+ Decays
227 x 106 B0 Mesons
Count B0K-+ Decays
Is N(B0K+ ) equal to N(B0K-+ )?
CP Violation in Bo K Decays
BABAR
background
subtracted
0
0
9
696
10
n B K
n B K
CP
Br B f Br B fA
Br B f Br B f
K. Honscheid, Ohio State University, C2CR 2007
Golden mode B0J/Ks:CP eigenstate, high rate, theoretically clean
Mixing Induced CP violation
B0 J/Ks
ei0
ei0
No weak phase
B0ei2
Two Amplitudes Interference ACP ~ sin2
Two Vtd vertices ei2
+
K. Honscheid, Ohio State University, C2CR 2007
(4S)
t =0
A Complication: Quantum CoherenceWe need to know the flavor of the B at a reference t=0 Flavor Tagging and measure the difference in decay time t Time Dependence
B 0
The two mesons oscillate coherently : at any given
time, if one is a B0 the other is necessarily a B0
In this example, the tag-side meson decays first.
It decays semi-leptonically and the charge of the
lepton gives the flavour of the tag-side meson :
l = B 0 l = B 0. Kaon tags also used.
tagB 0l (e-, -) =0.56
z = t c rec
sK
t picoseconds later, the B 0 (or perhaps its now a B 0) decays.
B 0
ll
d0B b
W
At t=0 we know this
meson is B0
Time dependent asymmetry ACP = SCPsin(mt)
CCPcos(mt) SCP = fCP sin2(fCP= ±1), CCP “direct” CP violation = 0 for
J/K
K. Honscheid, Ohio State University, C2CR 2007
CP Violation in B0J/Ks
t for B0 tag B0J/K
t for B0 tag B0J/K
Background
BaBar preliminary, hep-ex/0607107
Belle preliminary, hep-ex/0608039
B0J/KSB0J/KL
BellePreliminary
BellePreliminary
B0 tags
B0 tagsB0 tags
B0 tags
t asymmetry
J/KL is fCP= +1
J/KS is fCP= 1
t oscillation
Period = B mixing m
Amplitude = D sin2(Dilution D due to mistags; measured experimentally)
PRL 98, 031802 (2007)PRL 98, 031802 (2007)
K. Honscheid, Ohio State University, C2CR 2007
Extracting from sin2 has ambiguities; removed by J/K*, D*D*KS and D0//'/ analyses
Sin(2) World Average Heavy Flavors Averaging Group
E.Barberio et al., hep-ex/0603003
Statistics limited
Consistent with zero: no evidence for NP in tree decay
= 21.2o ± 1.0o
K. Honscheid, Ohio State University, C2CR 2007
Is “” Universal?
)(/
/
,,)2(
/
000*0*
0
001
0
0
S
L
ScScS
S
KKKJ
KJ
KKKS
KJ
**0
*
,/
,
DDJ
DDDD
0
00
000000
00
)980(,
,,,
,,
SS
SSSS
S
KfK
KKKKK
KKKK
m)(charmoniu a) sccb
)charmonium (andcharm b) dccb
sssbsddb ,dominated-Penguin c)
Can use 3 different categories of B0 decays to measure :
golden mode
0K
0B
b
s
s
s
d d
Possible contribution from New Physics (NP): new
heavy particles in the loop
See the following talkby Tom Browder
News Flash
hep/ex 0702031
BD+D-
S = -1.12 ± 0.37 ± 0.09A = 0.91 ± 0.23 ± 0.06 (= -C)
(expected to be close to 0)
K. Honscheid, Ohio State University, C2CR 2007
Let’s try this for the next angle: Access to from the interference of a b→u decay () with B0B0 mixing ()
d
d
0B
*tbV
tdV
b
b
0Bt
t
*tdV
tbV** // tdtbtdtb VVVVpq
B0B0 mixing
du
dd0B
ubV
*udV
b u
Tree decay
ubudVVA *
)cos()sin()( tmCtmStA dd
sin
)2sin(1 2
C
CS eff
ii
iii
eePT
eePTe
2
du
dd
0B
gb
utcu ,,
Penguin decay
tbtdVVA *
Inc. penguin contribution
0
)2sin(
C
S
222 iii eeeA
A
p
q
How can we obtain α from αeff ?
Time-dep. asymmetry :
NB : T = "tree" amplitude P = "penguin" amplitude
K. Honscheid, Ohio State University, C2CR 2007
How to estimate |eff| : Isospin analysis
Gronau, London : PRL65, 3381 (1990)Gronau, London : PRL65, 3381 (1990)
)( 0 BAΑ
)( 00000 BAΑ
)( 00 BAΑ
2| eff
|
)(~ 0 BAΑ
)(~ 00000 BAΑ
Limiting factor in analysis
K. Honscheid, Ohio State University, C2CR 2007
Measuring in B hep-ex/0607106
±0
0
0
0
6
572 53
(5.12 0.47 0.29) 10
0.019 0.088 0.014
N
BR
A
0 0
0 0
0 0
6
140 25
(1.48 0.26 0.12) 10
0.33 0.36 0.08
N
BR
C
0 0
°@90% C.L.
hep-ex/0608035
1464±65
S+- = -0.61 ± 0.1 ± 0.04A+- (=-C) = 0.55 ± 0.08 ± 0.05BR+- = (5.1±0.2±0.2) x 10-6
+-
K. Honscheid, Ohio State University, C2CR 2007
Sometimes you have to be lucky
0.0150.013,
6
0.977 0.024
(23.5 2.2 4.1) 10
Lf
BR
615±57
0
0
0
6
0.0230.027,
(16.8 2.2 2.3) 10
0.905 0.042
0.12 0.13 0.10L
BR
f
A
390±49
0.05 0.070.19 0.21
0.07 0.15 0.06
S
C
0 0
0 0
0.37 60.36
0.110.13,
(1.16 2.7) 10
0.86 0.05L
BR
f
323198 22
•B is almost completely polarized
•B is small better constraint on
hep-ex/0607092hep-ex/0607097
hep-ex/0607098
B B B
K. Honscheid, Ohio State University, C2CR 2007
Combining all methods:
Combined: = [93+11
9]
CL=0.683
Other solutions disfavoured
Global Fit = [ 98+5-19] º
Global fit without :
K. Honscheid, Ohio State University, C2CR 2007
= arg[Vub*]: CP violation in DK modes
Relative phase = ei
B+
D0K+
ei
ei
V*ub vertex ei
E.g. B+D0 /D0K+
D0K+
D0/D0 CP state (GLW)D0/D0K+/K+, CA/DCS (ADS)D0/D0KS+, Dalitz (GGSZ)
D decays do not involve Vub or Vtd: no contribution to phase
GLW: Gronau, London, Wyler (2001)
ADS: Atwood, Dunietz, Soni (1997)
GGSZ: Giri, Grossman, Soffer, Zupan (2003)
ei
ei
B± DK: no time dependence; extract from rates and CP asymmetriesbut b u amplitude is small (for example rB (DK−) = 0.16 ± 0.05 ± 0.01 ± 0.05 Belle)
K. Honscheid, Ohio State University, C2CR 2007
The GGSZ method – an example
BaBar preliminary; hep-ex/0607104
Belle; Phys.Rev.D 73, 172009 (2006)
Belle Belle
Map out Dalitz plot from all D0 Ks+- decays
B+B
Look for deviations in B±D0K± plots
K. Honscheid, Ohio State University, C2CR 2007
Combined Result for
Indirect (CKM) = [59+94]
Combined: = [62+38
24 ]
K. Honscheid, Ohio State University, C2CR 2007
The CKM Model has passed the experimental test
New TargetsEffects of TeV new physics deviations from SMLFV and new source of CPVHidden flavor symmetry and its breaking
[21.2 ± 1.0]o (0,0)
[93 +11-9]o
[62+38-24]o
K. Honscheid, Ohio State University, C2CR 2007
The next few years (2007 – 2010)
• Belle and BaBar• 1 ab-1 (2006)• 2 ab-1 (2008)
• Tevatron• 2 fb-1 (2006)• 8 fb-1 (2009)
• LHCb is nearing completion
0
200
400
600
800
1000
1200
Ju
l-9
9
Ju
l-0
0
Ju
l-0
1
Ju
l-0
2
Ju
l-0
3
Ju
l-0
4
Ju
l-0
5
Ju
l-0
6
Ju
l-0
7
Ju
l-0
8
ICHEP08
K. Honscheid, Ohio State University, C2CR 2007
LHCb Prospects (Some of the things they can do)
Bs Mixing phase (s) using Bs J/Signal yield: 130k events per L=2fb-1 with a B/S0.1, Sensitivity s ~ 0.021Sensitive probe of New Physics effects in the Bs mixing
s = s(SM) + s(NP) with s(SM)=-22 ~ -0.037±0.002
0,0
0,2
0,4
0,6
0,8
2006 2008 2010 20140,00
0,01
0,02
0,03
0,04
2006 2008 2010 2014
now
pre-LHCbLHCb atL=2fb-1
LHCb at L=10fb-1
year
( s
)
year
now pre-LHCbLHCb atL=2fb-1
LHCb at L=10fb-1(
s)
Sensitivity to Standard methodsGolden Mode Bs DsK
Sensitivity ~ 4.2o with 2 fb-
1
0
4
8
12
16
20
2006 2008 2010 2014
()
[o]
now
pre-LHCbwith LHCbat L=2fb-1 with LHCb
at L=10fb-1
year
V. Vagnoni CKM2006
K. Honscheid, Ohio State University, C2CR 2007
%7.4/)(
%17/)(
Summer 2006
From B-Factories to LHCb – without new physics
%3.3/)(
%4.7/)(
2008* LHCbLHCb
L=10 fb L=10 fb-1-1
%8.1/)(
%6.3/)(
2014
K. Honscheid, Ohio State University, C2CR 2007
Super B-Factory Plans at KEK and Frascati
Interaction RegionCrab crossing
=30mrad.y*=3mm
New QCS
Linac upgrade
More RF power
Damping ring
New Beam pipe
L = 81035/cm2 /sec
Design Luminosity ~ 1 x 1036 /cm2/secSynergy with ILCRecycle components (PEP, BaBar)Lots of R&D needed
KEK Frascati
IP
ILC ring ILC FF
K. Honscheid, Ohio State University, C2CR 2007
SummaryCKM Model is now a tested theory
Great success for theoristGreat success for experimentalistGreat success for the Standard Model = (93+11
-9)o
= (21.2 ± 1.0)o
= (62+38-24)o
Search for Deviations from SM and New PhysicsNear Term Future Looks Promising
B Factories only half way doneTevatron will triple data sampleLHC(b) turn on
Long Term ProspectsLHC(b) upgradesSuper B Factories (KEK, INFN)