Search for New Physics in B decays
Tadashi Yoshikawa Nagoya U.
KEKPH07 3/1 – 3/3
Kobayashi-Maskawa Theory ( CKM matrix) are almost confirmed !!
We are going to next stage to search for
New physics hiding well !
Unitarity Triangle :
Where are they hiding ?
Where can we find them in ?
direct search
VS Indirect search
tree loop
High energy exp. High luminosity Exp.
Both approach are important to understand (find) new Physics .Physics are going to indirect search of New Physics .They will give us some useful hints and strong constraints for new
Physics.
Example: Ishidori and Paradisi (hep-ph/0605012)
TeVu = -1.0 TeV
Constraints for tan and charged Higgs mass in the MFV within the MSSM.
A Case:
g-2
(Belle)
Main Targets are in Penguin processes .
b su
ud d
Bd
b – s(d) gluon penguin
b – s(d) electro weak penguin
……
..
They will give us some useful hints and strong constraints for new Physics.
Searching for New Physics in B decays
Investigating Penguin effects.
How to handle these penguin processes?
How to play with How to play with penguin. penguin.
b du
ud d
Bdπ +
π -
Plan of this talk:
IntroductionStatus of several puzzle
Scp of B ’K K puzzle Still remaining the window for NP ?
BV ll and BKp ll
Time-dependent CP Asymmetry : Bigi and SandaBigi and Sanda
cc mode S penguin
No CP phase in diagrams No CP phase in diagrams
b
BB
c
B
b
c
s
J/
K
K
J/
B
b
s
ΦΦ1= 21.21= 21.2 ±±1.1.0 0 °°
Discrepancy of Scp between CC modes and b-s modes
in the SM
The EX. Data are moving to the SM direction !!
Comparison by CP asymmetryTime-dependent CP asymmetry: Time-dependent CP asymmetry:
Af direct CP violation
Sf mixing CP violation : M (phase of B-B mixing) ~1
D (phase of A(Bf) )
Almost 0!!
New Physics window is still remaining ?
SM
discrepancy
SM
SM
SM
How do you think about this situation ?
Still remaining deviation.
There were many many works to explain these deviations,
SUSY, extra D model ………
It will give us several useful hints or constraint to build new model !!
As the Next step, we should consider comparison among each decay modes even if the modes are b-s penguin. We have to investigate carefully the detail each contributions.
New Physics is hiding them !!
SK0may have some hints of New Physics.
SK0pi0 = 0.31 0.26
Kpuzzle
Kim, Kwon, Lee, TY
Present status of the Puzzle Lipkin
Yoshikawa( 03)., Gronau - Rosner, Buras-Fleischer et al ,
Li, Mishima and Yoshikawa(04) ……. Many works.
What was the Puzzle ?
. Discrepancies from expectations by Sum ruleSum rule among the branching ratios.
(Theory)
(After ICHEP06)
Still remaining this Problem ??
History of Rc - Rn
Rc – Rn Rc
Rn
The EX. Data are moving to the SM direction !!
0 or not
2006 HFAG
What can we learn from the K pi puzzle ?
Diagram Decomposition Gronau, Hernandez,London, Rosner
Relation among amplitudes : Isospin relation
Several Sum rules for Br and Acp .
B decays : topological diagram topological diagram decompositiondecomposition
TTrreeee
QCDQCD PPengenguinuin
CColor olor suppressed suppressed
treetree
EElectrolectroWWeakeak
PPenguin (enguin (PPEWEW))
AAnnihilatinnihilationon SSinglet QCD inglet QCD
PenguinPenguin
CColor suppressed olor suppressed
EWEW PPenguinenguin
((PPCCEWEW ))
Gronau, Hernandez,London, Rosner
b
B
B
B
BB
B
B
bb
b
b
bb
Hierarchy Hierarchy AssumptionAssumption
PQCD
in B in B K K
O(0.1)
O(0.01)
Naïve factorization method
(Leading order)
Branching ratios under the Branching ratios under the assumptionassumption
by neglecting r2 terms including rC, rcEW , rA (smaller terms than O(0.01 ). )
=0.21=0.21 ±± 0.11 0.11 ≠ ≠ OO(0.1^(0.1^2) (2005)2) (2005)
Rc - Rn Rc - Rn
The Origin of Sum rule breaking is Electro Weak Penguin ??
rEW : Electro Weak Penguin Contribution
=0.12=0.12 ±± 0.10 0.10 OO(0.1^2)(0.1^2) ( ( ICHEPICHEP06) 06)
The difference comes from r^2 O(0.1^2) terms !!!
Rc – Rn
EW)
Strong phase of EW penguin
rew = 0.14, 0.2, 0.3, 0.4
Maximum of Rc – Rn for delta(EW) and rew
Cos T > 0 is favored. T should be around 15o.
Fleischer-Mannel bound
-0.093 0.015
as a function of T with rT = 0.2 .
CPA T should be around 15o or 1
55o
T
++
Direct CP Violation of B K+
What can we expect
No strong phase difference between tree and EW(Z) penguin
bbWWzz
us
K
K BB
1)
2)
under SU(3) symmetry. Because the diagrams are topologically same.
tree
EW Penguin
Neubert-Rosner,
Buras and Fleischer
Rc – Rn
EW)
Strong phase of EW penguin
rew = 0.14, 0.2, 0.3, 0.4
If the strong phases of tree and EW penguin should be same, small discrepancy is still remaining !!
If Rc – Rn keep the positive value,
EW penguin should have extra (new) phase.
New Physics window ?
Consider a case that EW Penguin including NP with New CP Phase.
New Physics solution
New Phase
EW)
Rc - Rn
rew = 0.14, 0.2, 0.3, 0.4
The maximum bound of Rc – Rn
for EW at EW) = and
rT = 0.2 and under constraint Acp.
EW)around 270o i
s favored
Relaxing the hierarchy assumption = keeping = keeping rr22CC terms terms in
Allowed
Allowed
prediction predictionrEW rEW
rC rC
Large rc solution in NLO PQCD -- Li, Mishima and Sanda PRD72:114005
Need 3 times larger
2) Direct CP asymmetry :
theoretically 、 1 > r_T ~ r_{EW} > r_C > r_A
New Physics ? In rNew Physics ? In rEW EW EW penguin ? EW penguin ?
expectationexpectation BUT BUT differentdifferent !!!!
Experimental data,
or Large rc contribution ?
Direct CP asymmetries in B in B K K
Relation among the CP asymmetries : (SUM rules)
Large EW Penguin ? Or Still Large EW Penguin ? Or Still early ?early ?
Consistent Consistent ??
Direct CP asymmetries in B in B K K
Relation among the CP asymmetries : (SUM rules)
Still depend on Acp00 . Need more precise Still depend on Acp00 . Need more precise data!! data!!
If EW Penguin : ( Z penguin ) : should include new phase,
the effect will appear in semi-leptonic decays .
But to investigate the effects in C10 process is slightly difficult !!
CP asymmetry of B ll or B Xs ll
tiny Br
final states are both CP odd and even .
Need angular analysis of B K pi ll .
Let’s consider semi-leptonic decays
BK* l l decay matrix element
b-s Tiny contribution in SM
Z penguin
B (K* K ) + l l
l^-
l^+
l
K
Forward-Backward Asymmetry
l^+ l^+
How to detect the evidence of New Phys. by B K* ll .
Using Forward-Backward asymmetry:
The zero of FB asymmetry is rather insensitive to hadron uncertainty .
We need to remove the hadronic uncertainty !!
We should use some asymmetries :
C7
-C7
AFB
z = (pl^+ + pl^-)^2 Dilepton invariant mass
AFB
V, Ti, Ai : B-K* Form Factors
B K* ll
How about BK pi l l decay ?
Depend on C7 and C9.
C7
-C7
The angular distribution : definition of the angles
z
l+
l -
K
π
K* γB
θl
φ
θl : angle between l+ momentum direction and z axis
at CM system of (l+ l- )
: angle between π direction and - z axis at CM of (K pi )
φ : angle between 2 decay planes
FB asymmetry
There are 3 angles. Can not we use them ?
Using angle between decay planes:
An Example:
Grossman and Pirjol, JHEP0006: 029 hep-ph/0005069
Kim, Kim, Lu and Morozumi, PRD62:034013 hep-ph/0001151
Points: Using small-q^2 region, ( q^2 ~ 0 )
We can neglect 1) local interactions with O9, O10
2) longitudinal modes, A0
One can investigate B Vγ by using polarization analysis or angular distribution
A : CP-even
A⊥ : CP-odd
=Time dependent CP
From angular distribution analysis
in B K pi ll decay
After integrating angles and q^2 at small region, approximately,
From the distribution for angle φ + B->V γ 、 one can extract
which may be including new physics info.
Angler analysis
C7 C7’
whereSmall contribution in SM
The branching ratios is
After integrating all angles, remains as the decay rate. The other terms shown the angular distribution.
B K l l mode
CP: odd
CP: even
CP: odd
CP: odd
CP: odd
CP: even
Kruger,Sehgal, Shinha, Shinha
Kruger, Matias
If Possible, we would like to extract these contributions by
using FB asymmetries.
FB asymmetry for l^+
Triple FB asymmetry
An asymmetry for
Triple FB asymmetry
Double FB asymmetry for and
CP: odd
CP: even
CP: odd
CP: odd
CP: odd
CP: even
CP Asymmetries
Direct CPA
Strong phase difference CP phase
Need strong phase difference !!
Ceff9 の imaginary part (Buchalla 00)
C9 is including strong phase comes from CC resonances
However no phase in low q^2 region !!
FB asymmetry for l^+
C7
-C7
C10 i |C10|
AcpFB2
C9 i |C9|
FB4
If C7’ with CP phase exists, the effect will appear in FB4 and Acp .
C7’ not =0
If C7’ with CP phase exists, the effect will appear in FB4.
FB5
Triple FB asymmetry
C7’ not =0
If C7’ with CP phase exists, the effect will appear in FB5.
C10 i |C10|
FB6
Double FB asymmetry for and
C7’ not =0
C7
-C7
C10 i |C10|
We can also consider time-dependent CP of FBi .
We need more strong phases .
How about interferences between K^* and scalar resonance as intermediated states.
We may get many fruitful information from B K pi ll decay modes.
Angular analysis
CP asymmetries
Summary There are several discrepancies between Ex. and theory in B decays. But some ones seem to be moving to SM prediction.Still remaining the region for New Physics in
Scp and Kpuzzle Color suppressed tree ? Or Electro weak Penguin ?
They are including fruitful information to build new physics model.