# Presentation: 036612

## CKM Unitarity anglesand Recent results from the B factories.)Hassan JawaheryUniv. of MarylandLepton-Photon SymposiumFermi 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 ******

_**The Unitarity Test**_

- CP

_**Definitions**_

** ****Both involve  V****ub**

********************************

## Constraints from the CKM fit |Vub|, |Vcb|, K, md , ms

**   **

- 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. H**oe**cker et al, Eur. Phys. Jour. *
*C21 (2001) 225, [hep-ph/0104062]*

## 


****

************************************************************
*****************************a******1***************....**

**Tree diagrams are not alone: **

**********************************************************************..******

-  CKM suppressed

**Penguins (gluonic & E.W) can also lead to the same decays:**

**Main source of info on ********and ************Decays involving ****b********u ****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**

## +

**+**

- B-  DCPK-

_**II- **_**Decays involving interference of  b********u W****-**** &  b********c W****-****  Processes**
**(Penguin Free)**

**Involves arg(V****ub****)=******

**B********DK:**

******dependence of  rate and direct asymmetry**

**B****0********D******************

**+**

**Direct CP  asymmetry sensitive to sin(2******

** ****arg(V****ub****)=******

**Same final state via B****0**** mixing & b********u**

## Experimental Observables

- With Tree and Penguins both in action:

**To constrain ******** requires estimates of:**
**| P********/T********|********&  relative strong phase ******

**Branching fractions for various non-charm B decays**
**Time Integrated (Direct) CP asymmerties**

## More observables: Time – Dependent CP Asymmetries

**With Tree alone**

** ****Time evolution of  tagged B****0**** decays, e.g. in the case of *****B******0****** ************ *********************************

- CPV due to mixing and decay interference

- Direct CPV in Decay

**With Penguin and Tree**

**S=sin2********eff**
**************eff ****–******
**C**** ******** 0**

***Belle:***** A****f **** =  - C****f  ****(*****BaBar)***

## A few comments on the already established  pattern from charmless 2-body decays

**Connected via Isospin symmetry *****(Gronau &London) (*****Isospin engineering)**

****

**With Tree alone,expect:**** **

**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**

## 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 (S********0) deviating from (sin2*********i************e*****. 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**

## 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 Machine
140 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**

## Analysis Issues for Rare B Charmless decays

**Looking for modes with Br~10****-6 ****to 10****-5**** **
**Continuum qq(bar) background at 10****3**** larger than the signal**
**   ****BKG Suppression using event shape & topology, kinematics, particle ID,..****         **

- Kinematic variables:
*******E=E******beam******-E******B***
-  provides separation of KK, K, decays

- Signal Monte Carlo

********

********

**Other info into analysis:**
** ********t=********z/<c******
**Flavor tag of other side**
**Particle ID, event shape,..**

## 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******

****************

##  (BaBar)

**Time Dependent CPV in ****B**************************

** ****(*****BaBar)***

**Asymmetry****          Events/1ps**

** ****(*****Belle*****)**

**B****0 ****tag**

**B****0**** tag**

**Fits to: **

** *****81***** *****fb******-1***

***78 ******fb******-1***

******t(ps)**

******t(ps)**

## New Results:BaBar Update of CPV measurements with full data sample (Run 1+2+3): 113 fb-1  on Peak data

**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**

**B****0 ****tag**

**B****0 ****tag**

## 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.**

******gnoring the large ****************~2 ********)**

## BaBar: The decay B

**Significance: 4.2******** **

**Used their full data set (113 fb****-1**** ) **
** ****Measured  Br(B****************************Br(B****************************x10****-6**** ] **
**Control over a major background source. Br about half of previous assumed value**

****************

** ****qq bkgd**

**Fischer Discriminant**

**signal**

******Observation**

## Belle: The decay B

**Analyzed full data set of 140 fb****-1**** **
**From a fit to 2-dimensional distribution of Mes and ********E **
**Find:**

**Significance:3.4 ******

******Evidence**

## What about All but one piece is in place

| 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 |

**What about ********All but one piece is in place**

**For a full Isospin analysis need: C************direct CPV)**
**                              ****&                              **
**Still some constraint can be set using the measured average Branching fraction:**

**(Quinn- Grossman),**

** ****With WA Br(B******** **********************
******eff ****|************ at 90% c.l. **

**Not much improvement on QG bound**

****

**Not a very useful limit  & don’t expect more than ~10****o**** improvement in future.**

## Summary of measurements of BDecays

**See 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*****)**

**Evidence Direct CPV ?**

## 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?**

##  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 using**
**B->****K****0********+**** & ****B************l******** , B******** ********0********+**
**(with use of SU(3) & factorization)**
**Here calculate S & C for |P/T|~0.3**
**Unconstrained strong phase ******** **

**BaBar**

**Physical boundary**

**Belle**

**BaBar**

**My Average **

## In all scenarios data can accommodate the range of from the SM CKM fit

***(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 **

## Constraints on  Connecting the BK data via symmetries

**Useful ratios of branching fractions and ps-asymmetries with sensitivity to ******

**Constraints on  ********Connecting the B********K******** 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|**

## 1 range of R0

**1 ********range of R****0**

**60 < ********at 1 ********level**
**No useful limit at 2 ********level**

**Consistent with CKM range:**

****

**R****0**

**A0=-0.06(A0+1******

**A0=-0.12(A0-1******

**Gronau & Rosner method hep/ph-0307095**
** ****(R0 vs ******** for fixed A0**

**R****0**

## Other channels of reaching  

_**B**__****__****_******CPV 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 B****0********”************“********************B****0********”************”************************updated for this conference with their full data sample.**
**1****st**** 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. ****B****************has been measured and shown to be dominated by the CP even component – good news for CPV studies.**

## 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:**

**Dilution (**_**Non CP parameters**_**): ********C************  & **** ********S**********

## 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
 | -0.130.18
 | 0.33 0.18
 | -0.110.06
 | 0.18  0.12
 |

- 

- 

- 

- 

## Test Of Direct CPV

- 2.5 
- (2.7 if stat. only)

- 99%

- 90%

- 98.6%

- Define two
- asymmetries:

**Test Of Direct CPV**

## A promising channel:the B system

**The Channel to watch in Future**

**The components of  B************are identifeid: B****0****************************(BaBar),********B****+********************************elle & BaBar)**
**Decays nealy 100% longitudinally polarized [****CP-even]**
**Limit has been set on B****0**************************

**See John Fry’s talk this morning for more detail**

**>2 times more restrictive than B************system**

**A promising channel:the B************ system**

## Reaching 

******via **
**(b********u(cs) & b********c(us) interference:**
**B********DK  Decays**

*Method and observables suggested by Gronau, Wyler,Atwood,Dunietz, Soni,Quinn, Sanda*

## BDK Modes- No penguins

- In B-  DCPK- , the diagrams interfere & provide the sensitivity to **** :
- [DCP=(1/2)(D0 D0 ) ]

**r****DK ****(~0.1 –0.2)  & ********DK **

**Also unknown**

**Experimenters are very active in constructing the DK puzzle**

_**Observables**_

******DK triangle**

## B-→DCP K*-

**cos********hel ****fr****o****m  ****  P****→****PV**

- MK*-

**D****0 ****→ ****K********, ****K********,****K******** ****0**

**B****-****→****D****CP**** ****K*********-**

**B****- ****→**** D*********0 ****K*********-**

**B ****→**** D*****0 ****K*****-****      ****ALL **

**D*****0 ****→**** D****0******** ****0**** **

**D*****0 ****→**** D****0******

**B****0 ****→**** D**** ****K****0**

## (8.3 ± 1.1(stat) ± 1.0(sys)) x 10-4 & L/0.86 ±0.06 ±0.03 (BaBar)

|  | 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 |  |  |  |  |

**B********D****o****K****-**

|  | 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 |  |  |  |  |  |

**B********D****o****K*****-**

**(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 |
| --- | --- | --- | --- |
| B0DoK*0 | 4.8 ±1.1 ±0.5 | 3.0 ±1.3 ±0.6 |  |
| B0DoK0 | 5.0 ±1.3 ±0.6 | 3.4 ±1.3 ±0.6 |  |

| B0D*oK0 | <6.6 (90% c.l.) |
| --- | --- |
| B0D*oK*0 | <6.9 (90% c.l.) |
| B0DoK*0 | <1.8 (90% c.l.) |
| B0D*oK*0 | <4.0 (90% c.l.) |

**The B********DK puzzle under construction**

**V****ub**

**V****ub**

## What about Current errors are still too large to allow for simultaneous extraction of ratio of (bc) and (bu) amplitudes (rdk) and the strong phase.  Need many fold more data. (may be possible with 500 fb-1)

**With assumptions on (r****dk****): mild limits can be extracted. *****e.g M. Gronau (hep-ph/0306308): ***** ****************at 1 sigma level.**

## Reaching sin(2

**via**
** ****(b********u(cd) & b********c(ud) interference **
**(& B****0**** mixing)**
**B****0********D****(*+) ********-**** **

*Method and observables first suggested by Sachs,Dunietz*

## B0D(*+)- Modes

- Dominant diagram b  c transition

- Suppressed diagram b  u transition

- Time evolution:

- Small asymmetry expected

## BaBar

**II - Fully reconstructed **
**B****0********D****(*+)********-**** Decays**

- Lepton tags

- kaons tags

**Belle**

**Fully reconstructed B****0********D****(*+)********-**** Decays**

**I- Partially reconstructed B****0********D*****+********-**** Decays: (number of events)**

**2******

## Interpretation:BaBar’s attempt 

- Use measurements of B0D(*+)sto estimate r(*)  (Factorization & SU3 correction )

**Interpretation:BaBar’s attempt **

**Favors the CKM favored solution to sin******

## 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 B************shows 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 B****************************WA: 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 (B********DK & D********* are beginning to contribute to constraints on CKM parameters & many new B********DK 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****.**