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1
A New Physics Study
in B K & B K* Decays
National Tsing Hua University, October 23, 2008
Sechul OH ( 吳世哲 ) ( 오세철 )
C.S. Kim, S.O., Y.W. Yoon, PLB665, 231 (2008)C.S. Kim, S.O., C. Sharma, R. Sinha, Y.W. Yoon, PRD76, 074019 (2007)
2
The The B K puzzle puzzle
A model-independent analysis of B A model-independent analysis of B K K
-- reparametrization invariance reparametrization invariance
-- how to extract New Physics effects-- how to extract New Physics effects
A model-independent analysis of B A model-independent analysis of B K* K*
-- interesting observables sensitive to New Physics -- interesting observables sensitive to New Physics
effectseffects
SummarySummary
3
4
5
6
Cabibbo-Kobayashi-Maskawa (CKM) matrix
Unitarity:
Unitarity triangle:
7
Direct CP violation in decay occurs when
Direct CP violation
Time-dependent CP violation
= J/ Ks
8
9
q
q-
The dominant quark level subprocesses are loop (penguin) processes b s penguin is sensitive to NP
The 4 decay channels (& antiparticle decay channels)
10
Large
Small
Conventional Hierarchy in B → KConventional Hierarchy in B → Kππ
strong penguin
EW penguin
color-suppressed tree
11
Branching Ratios
Fleischer Hep-ph/0701217
March 2007:Rc = 1.11 ± 0.07Rn = 0.97 ± 0.07
= 0SM :
12
CP Asymmetries
SM :
13
Amplitude parameterization
( )
( )
0
0
0
0 0 0
( )
2 ( )
2
CEW
CEW EW
EW
A B K
A B K
A B K
A B K
p
p
p
p
+ +
+ -
+ +
¢ ¢® = +
¢ ¢ ¢® = - - -
¢ ¢ ¢ ¢ ¢ ¢® = - - - - - -
¢ ¢ ¢® = - -
P A
P P T
P P P T C A
P P C
* *tb ts tc ub us uc tc ucV V V V¢ ¢ ¢ ¢ ¢= + º +% %P P P P P
l 2 l 4
Hierarchy between the parameters
tc¢P
EW,¢ ¢T P
CEW,¢ ¢C P
uc,¢ ¢A P
1
l2l
3l
q
q-
14
Final form
( )A B K A Pp0 0 + + + ¢® º = -
( ) ( )T C EWi i i i i iT C EWA B K A e P r e e r e e r ea g d g d dp
00 0 11
2
+ ¢ ¢ ¢+ + + ¢® º = - - +
( ) Ti i iTA B K A e P r e ea g dp0 (1 )
+- ¢+ - +- ¢® º = -
( ) ( )C EWi i i iC EWA B K A e P r e e r ea g d dp
000 0 0 00 11
2¢ ¢¢® º = - - +
We neglect We set the strong phase of P to be zero all phase is relative to it We hold 7 unknown parameters We use value given by other analyses are real and positive, are phases of their amplitude
, ,Cuc EWP P A¢ ¢ ¢
¢ ¢ ¢ ¢, , , , , ,T C EW T C EWP r r r δ δ δ
ijA ija
EWtc T C EW
tc tc tc
P r r r, , ,¢ ¢ ¢
¢ ¢= = = =¢ ¢ ¢
T C PP
P P P
15
NP term is absorbed into SM term:
( )C EN N
N
W
C EWN
i i iC EW
i i i
N i i
N Nii
C EN N
Wi
A A P r e e r e
P r e e r e
r
re
e e
r e e
f d
d
g
d
d d
g d d g ggff
g
0 00 1,
2
1 )2 sin sin
sin sin(
¢+
¢
¢É - + +
æ ö- ÷ç¢= - + + - ÷ç ÷ç ÷çè ø
CMC
NMN
i N iC C
ir ee r e rd d dfgsin
sin¢= -
EWMW
NEM i
E
NN
W EWiir ee r e rd d df g
gsin( )
sin¢ -
= -
( )CMEW
MM iC
ME
i iWP e e er rdg d1
2= +-¢
““Reparametrization invariance” of decay amplitudes Reparametrization invariance” of decay amplitudes Botella and Silva
16
Original Form does not change:
If there is NP,
( ) ( )
M MC C
M MEW E
C SM C SM
EW EWSM SMWr
r
r
r
d
d d
d
( ) , ( )
,
¹ ¹
¹ ¹
( )A B K A Pp0 0 + + + ¢® º = -
( ) ( )MCT
MEWM i
EWi i i i
TM iCA B K A e P r e r e re eea g d g ddp
00 0 11
2
+ ¢+ + + ¢® º = - - +
( ) Ti i iTA B K A e P r e ea g dp0 (1 )
+- ¢+ - +- ¢® º = -
( ) ( )MEW
MCM i M i
C Ei
WiA B K A e erP ee r da g dp
000 0 0 00 11
2¢® º = - - +
17
P Br +¢µ 0
CPT
CP
T CP T
RR
A R
r R
gd
g g
g d
+-
+-
+-
é ùæ öæ öê ú- ÷ç ÷ç ÷ç¢= ± + - - ÷ê úç ÷ç ÷÷ç ÷ççê ú- ÷è øçè øê úë û
¢= - -
2
2
sin2 1cot 1 1 1
( ) cos 2sin
(1 cot cot ) 1
A
A
Analytic Solution
MEW
ME
MC
MC
W
y yyy
y yyy
y yy y
y yy y
r
r
d
h hg
g h hg
h hh h
h gh g g
d
h gh
+= - -
+= - + -
æ ö- ÷ç= - ÷ç ÷ç ÷ç -è ø
æ ö- - + ÷ç ÷= -ç ÷ç ÷ç - - +è ø
2 2
2 2
1cos( )
sin 2
1cos(2 )
sin 2
cos cosArcTan
sin sin
cos( ) cos( )ArcTan
sin( ) sin( )
MEC
M
W
MEW
M
C
M iEW
M iE
M iC
M iC
i
W
i i
i i i
Ae e ye
PA
e e y
rr e
r e
e
r e eP
g a h
g a h
d d
dd-
- + = + º¢
- + = + º¢
00
00
00
00
2 1
2 1
A A P xA P x
A A P xA P x
a z
a z
+
+
æ ö¢- - ÷ç ÷= ± ç ÷ç ÷¢ ÷çè ø
æ ö¢- - ÷ç ÷= ± ç ÷ç ÷¢ ÷çè ø
2 20 00 2 200
00
2 20 00 2 200
00
2 2ArcCos
2 2
2 2ArcCos
2 2
18
4 different solutions for
We reject “Cases 1 & 3” due to predictions different from data The SM estimate
0sKπ
S= > = » - =0.12 0.039, 61 , 22EW C C EWr r δ δo o
, , ,M MEW EW
M MC Cr δr δ
0=0.38 0.19(data)SK
Sp
±
Case 2: Large C Case 4: Large EW
( 4-fold discrete ambiguity )
19
Find solutions for NP term
CMC
NMN
i N iC C
ir ee r e rd d dfgsin
sin¢= -
EWMW
NEM i
E
NN
W EWiir ee r e rd d df g
gsin( )
sin¢ -
= -
4 real equations vs 7 unknowns: , , , , , ,N N NC EW C EWr r δ δ r φ δ¢ ¢
Need at least 3 additional inputs to fix NP terms
20
Additional inputs from flavor SU(3) symmetry
From B decays
Assuming no NP in B
Additional inputs
21
B parametrization
( ) T C
T
C
i i i i
i i i
i i i
A B Te e Ce e
A B Te e Pe
A B Ce e Pe
g d g d
g d b
g d b
p p
p p
p p
+ +
+ - -
+ -
® =- +
® = - +
® = - -
0
0
0 0
2 ( )
( ) ( )
2 ( ) ( )
with 5 parameters T C
P
Tδ
Cδ
-fitting with 5 measurements3 Br’s, ( ),CP π π
A π π S + -+ -
p p +-
0 0 0.33CP 0.31( )=0.36 (data)A
us
ud
VC C
V¢= = ±(3.8 0.4)eV
EW T Ci i iEW T C
b
c cr e r e r e
c c Rd d d
l¢ ¢ ¢+
= - ++
9 102
1 2
3 1( )
2
C C
EW EW
r
r
d
d
¢ = ± - °± °
¢ = ± °± °
( , ) (0.076 0.008, 12 15 )
( , ) ( 0.14 0.04, 9 10 )
Gronau, Pirjol, Yan (1999)
22
Li, Mishima, Sanda, PRD72, 114005 (2005)
C C
EW EW
r
r
d
d
¢ = - °
¢ = °
( , ) (0.039, 61 )
( , ) (0.12, 22 )
Additional inputs from PQCD result
23
Solution for NP term with additional inputs
MC C C
MEW EW EW
i M i iC C C
i M i iEW EW EW
r e r e r e
r e r e r e
d d d
d d d
¢D
¢D
D º -
D º -
or
sinsin( )
sinsin
NC C
NC
NEW
NCN
rr
r r
d d d p
ff g
gf
= D D -
D=
- D
= D
NC
NEW
Ni N i
C
Ni N i
EW
r e r e
r e r e
d d
d d
fg
f gg
sinsin
sin( )sin
D
D
D = -
-D = -
Defining
With inputs from SU(3) symmetryWith inputs from PQCD results
Cases 2 & 4 are suitable and consistent each other between two methods.
Determining NP parameters
24
Dependance on g
25
Due to the Reparametrization Invariance(RI), the NP terms can be absorbed into the SM terms C & PEW in pair.
In order to extract NP parameters, we need at least
3 additional inputs. We could pin down each hadronic parameter und
er four-fold discrete ambiguity using analytic method. And also NP parameter for given additional inputs.
The result shows that there should be quite large NP contribution with a maximal weak phase ~ /2.
26
27
B → V V decays
by angular momentum conservation
B ! V1 V2
Spin: 0 ! 1 + 1 ) L = 0, 1, 2 or S, P, D waves
Sz : 0 ! 1 + (-1)
(-1) + 1 0 + 0
helicity: h S p
decay amplitudes:
In the B rest frame, the momenta of V1 and V2 are equal and opposite.
the helicities of both vector mesons are same.
1 2
28
* *1 1 2 2 1 2 2 1 1 2
1 2 1 2
( , ) ( , )b ic
A B V p V p ag p p p pm m m m
♦ The most general covariant amplitude for B V V
21 1a xA c
• Helicity basis
20 ( 1)ax bA x
• Transversity basis
1 1
1
2A AA 1 1
1
2A AA 00A A
1 2
1 2
wherep p
xm m
parallel transverse longitudinal
29
Total decay rate (in the B rest frame)
1
22 2
1 2 02
1V
B
B VV p A A Am
1 2 1 2
1
1/ 22 2 2 2( ) ( )
2
B V V B V V
VB
m m m m m mp
m
B Br
Longitudinal & Transverse polarization fractions
2
022 2
0
L
Af
A A A
2
22 2
0
Af
A A A
Standard model estimation:2
11L
b
fm
O
30
0 01 2 1 2Define ,B f f B f f A A A A
01 2
2 22 2
*( ( ) ) co2 2
s( ) Im( )sin( )tB t f f e mt mtq
p
A A A AA A
Time dependent measurement
Hamiltonian / 2 ( , : Hermitian)ij ij ijH M i M
11 22 by CPT invarianceH H
* *12 12
12 12
where q
p
M i
M i
For B V V decay modes,
01 2 0 0
01 2 0 0
B VV A g A g iA g
B VV A g A g iA g
A
A
22 2 22 2 2 * * *0 0 0 0 0 0Re Im ImA g A g A g A A g g A A g g A A g g A
2 2 2 22 2 2 * * *0 0 0 0 0 0Re Im ImA g A g A g A A g g A A g g A A g g A
( g depend purely on angles
describing the kinematics )
31
35 independent observables (18 magnitudes + 17 relative phases)
Time dependent measurement:
ObservablesObservables
32
Observables for B Observables for B K K [ Example of B [ Example of B P P case ] P P case ]
Only 9 observablesOnly 9 observables
33
An example of An example of New PhysicsNew Physics studystudy
beyond the Standard Model beyond the Standard Model
by using B by using B V V decays V V decays
B B K* K*
34
q
q-
B K* is a vector version (B V V) of B K (B P P)
The dominant quark level subprocesses are loop (penguin) processes b s penguin is sensitive to NP
We expect that NP contribution to B K* has the same nature as that of B K
B K* (B V V) provides enormously many observables
35
Large
Small
Conventional Hierarchy in B Conventional Hierarchy in B K* K*
strong penguin
EW penguin
color-suppressed tree
36
Parameterization of decay Parameterization of decay amplitudesamplitudes
Isospin relations:
Hierarchy relation in the SM:
37
Investigate how much sensitive to possible NP effects each observable for decays could be.
Assume that NP contributing via the EW penguins.
For simplicity, further assume that the SM amplitudes and are known (by additional information from somewhere, e.g. from future theoretical estimates). Thus, the SM amplitude is the only one modified by NP.
(SM part) (NP part)
38
Procedure:
(i) In order to determine the theoretical parameters, adopt the
minimization technique & use thecurrently available experimental data as constraints on the parameters.
(HFAG)
2
022 2
0
L
Af
A A A
: longitudinal polarization fraction
39
(ii) [number of data] < [number of parameters]
Try to fit the dominant strong penguins and their phases with , first.
(iii) Assume that the SM amplitudes ( ) follows the conventional hierarchy as in within the SM:
in PQCD,
(iv) Using the parameters determined, calculate all the 35 observables in the SM.
(v) To investigate the possible NP effects, consider two different cases.
(SM part) (NP part)
40
For illustration:
Very sensitive to NP:
41
For illustration:
Very sensitive to NP:
42
For illustration:
Very sensitive to NP:
43
For illustration:
Very sensitive to NP:
44
B K* decays: useful for New Physics study
certain observables are expected to be very sensitive to NP effects.
B V V measurements
B factories: Belle (KEK), BaBar (SLAC, closed),
LHC-b (CERN), Tevatron (Fermi Lab), Super-B (?)