Present and Future of B physics

Riccardo FacciniUniv. “La Sapienza” &

INFN RomeWIN’03

6-11 Oct, 2003

(1,0)

(,)

*

*

cbcd

ubud

VV

VV

*

*

cbcd

tbtd

VV

VV

(0,0)

B physics discussions of working group III + miscellanea

Outline Probing SM with B decays: The present

Angles of the Unitary Triangle Sides of the Unitary Triangle Rare B decays

Miscellanea physics muon g-2

Probing SM with B decays: The Future

New ideas

Recent developments

Future perspectives

The Unitarity Triangle & B Decays

B→B→Bs→

B→DKBs →DKBd →DB→/K

B(s)-B(s) mixing

B→/B→K*

Vtd/Vts

b→ulB→ll…

Vub measurement

b→clB→D*l

Vcb measurement

B→J/ Ks

B→ Ks

() ()

()

Measurement of Angles

CP violation in mixing and decay

Consider B decays to a mode f interference between mixing and decay

0B

0B

fCP

mixing

decay

tfA

fA

0t

t

f is not necessarily a CP eigenstate

( )0

2 2

( ( ) ) ~

1 (1 )cos( ) 2 Im( )sin( )

B t f

Mt Mt

*

2*

( )

( )itd tb

td tb

A B f V V Ae

A B f V V A

Mixing phase

f output

mixing B0lX,D(*),a1 0 ~0 MB0

“sin2” B0J/K0 + … 0 1 sin2

“sin2” B0 ~(-2) ~1 sin2

sin(2)

B0D(*)+ ~(-) ~0.02 sin(2)

Examples:

( )A

ArgA

Measurements of

d

c

dB

J/

K

b

s

d

c

dB

D(*)

Db

d

c

d

c

d

b

c

s

Charmonium K0

Penguin and tree have the same weak phase

d

c

d

b

c

dD(*)D(*) and J/0

Penguin and tree have different weak phases: asymmetry not necessarily = sin2

Kd

s

d

b

s

s

K0 and (‘)K0

Mostly penguin. In principle measures sin2, but sensitive to new physics

c

Talk from K.F. Chen

What’s new

SKs=-0.14±0.33 is 2.7 from SJ/Ks

But it is unclear if you can combine them

Important area to keep an eye upon [and do Dalitz analysis]

What if it is New Physics?Talk from K. Huitu

We write

For the amplitude

12

ii

K

SM

SUSY

eeRA

A

S

CP conserving strong phase

212

212

sincos21

22sin2sincos22sin

RR

RRS

SK

SUSY contributions:)()()( s

SUSYs

SMs KAKAKA

SUSY CP violating phase

12=0

Right Handed (New Physics) Currents

We could probe right handed currents in B physics with CP asymmetries in final states with different parity

(VV,AV,PP,PV). E.g. important new measurement of Ks0, but need to look also for f0Ks

Perform transversity analysis in VV modes (e.g. K*). >>‖ would signal new physics (hints in K*)

Measurements of triple products in VV modes can be hints of new physics but not necessarily with opposite chirality.

Talk from A. Kagan

Measurements of

d

u

dB

b

d

d

u

d

b

u

dPenguin and tree have different weak phases: asymmetry measures sin2eff

u

From sin2eff to sin2require isospin analysis

Long term:3-body dalitz analysis. Penguin to Tree ratio is fit in each point of the Dalitz plot

22 eff

progressesOld recipe:

• Fit S and C

• Measure Br(B0) and Br(B)

• Set an upper limit on Br(B0)

• … and find the limit on S– sin2

But …

… B00 IS NOT small !!!!!

20 0 1413 3

0 0 0 6

( ) 46 , 4.2

( ) (2.1 0.6 0.3) 10

N

B B

0 0 9.38.4

0 0 0 6

( ) 25.6 , 3.4

( ) (1.7 0.6 0.3) 10

N

B B

Current WA: 0 0 0 6( ) (1.90 0.47) 10B B

Talk from M. Cristinziani

BaBarBelle

Now we need ACP(p0p0) current error ~0.3

More recent developments

CPV in decays (with hints of direct CPV)

• measurement of several BF

• Starting 3-pion Dalitz analysis

• Studying events

Talks from M. Cristinziani and S. Swain

Measurements of

Talk from S. Rahatlou

No theo hypothesis

whatever

Contributions from bu transitions bring a dependence of CPV from Measure directly in direct CP asymmetries & B+ decay rates Measure with CPV in mixing

Two cases

d

u

dB b

d

cD

d

B

cD

A1~2c

b

d d

u

u

u

uB b

s

cD

A2~4c

A1~3c

u

c

uB

b

s

u

A2~3c

D

sin2: A2 doubly cabibbo suppressed

sin: A2 colour suppressed

No Penguin No CryM. Ciuchini

What’s new? constraints from D(*)

Evidences of from D(*)

BaBar

What’s new?Several B-D(*)0analyses

+ D0K- (D03 body Dalitz) from Belle

Lots of techniques, lots of fantasy, lots of fun!

Talk from S. Swain

This program requires CLEO-cTalk from K. Ecklund

Emiss - Pmiss

Monte Carlo

D0 Kl

D0 l

Tagged Events & Low Bkg

Stringent test of theoryDalitz analysis needed for DK studies

(3770) 3fb-1 30M DD

Ecm=4140 MeV 3fb-1 1.M DsDs

J/ 1fb-1 1000M J/

Phase

I

II

III

Charmless B decays and QCD factorization make a lot of PP and PV B

decays accessible to a systematic theoretical treatment

Few parameter handles need to be adjusted (in particular ms hadronic decays?)

When are we going to get VV calculations (such as )?

Talk from M. Neubert

at hadron colliders The presence of the Bs

meson opens a brand new set of interesting probes of gamma BsDsK is the theoretically

cleanest measurement of g The measurement of with

BsKK is not theoretically clean (U-spin is not conserved), but it is a good initial measurement

Talk from P. Rapidis

Measurement of Sides

BXl transitions

Talks from I. Bizjac, T. Brandt, R. Poling, and M. Rotondo

Semileptonic B decays provide pure method for determination of |Vcb| and |Vub| theoretical framework : OPE / HQE

Now sensitive to b-quark motion inside meson: b quark mass „“ nonperturbative QCD parameters

(-) kinetic energy squared of b-quark in B-meson „“ consistency checks of OPE / HQE

Reaching precision level high sensitivity to theoretical uncertainties

BXcl transitions

HX

,e

,e

(*)D

Y(4S)

K

K

(p* >0.9 GeV/c)

(p >0.5 GeV/c E>0.5 GeV)

high mass final states

Mx2[GeV2/c4]

B

B

From the mX and El distribution we can infer the B quark motion and measure Vcb

PRELIMINARY

Request: need higher moments

|Vcb|=0.0416(1±0.017|exp±0.010|(B)±0.015|

HQP) A. Stocchi I. Bigi

B D(*)l and Vcb

Request: need to remeasure the D*l form factors (only CLEO)

BXul transitions

Study the high tail of the lepton spectrum systematics from extrapolation Exploit the fact that the motion is

supposed to be the same in BXs decays

Request: separate B0 and B±

Exclusive BXul decays

Several new techniques are being developed l from Belle Q2 dependence from CLEO Fully reconstructed tags

from BaBar Request:

Form factor measurement (i.e. good q2 resolution)

Bl (pl > 1.0 GeV/c)

CLEO

Perspectives in semileptonic decays

Vcb from BDl as a cross check If check successful look for new physics in BD

Vub with q2 cuts not so wise since sum rules cannot be applied any more Least possible cuts and shape function from b sg (but

down to 1.8 GeV!!!!) Vub could go down to 5% You can get the useful info also from moments but you

need to go to higher ones

Overconstraints most powerful protection against ignorance Lenin’s dictum:

“Trust is good -- control is better!”

Talks from I. Bigi

Mixing measurements Measuring Md with great accuracy will

be worthwhile once Ms is measured (the ratio is less sensitive to theory)

Talks from

S. Burdin and G. Gomez-Ceballos

•D0: 2 fb-1, ms = 15 and t = 150 fs

• Single muon trigger: Bs Ds X (3.5), Bs Ds e X (3.5),Bs Ds (2.2), in the other side

• Dimuon trigger: Bs Ds X (3.0), in the other side

• CDF:

ms = 15, 2 limit with 0.5 fb-1

ms = 18, discovery with 1.7 fb-1

ms = 24, discovery with 3.2 fb-1

Projections from current lumi: ~100-150 pb-1

Also several lifetime measurements were shown

g-2 and Talks from H. Deng, K. Inami, and K. Tobe

Susy

a= (22±7 ± 4±8)10-10 [CDM-2 & CLOE]

= (7±6 ± 4±8)10-10 []

close to reach

- still blind (will have an error of 0.6 ppm) test CPT

dμ< 2.8×10-19e·cm (95% CL) electric dipole moment

The Future of B physics

The case for higher luminosity

While LHC will tell the existence of new physics, B-machines will tell the flavour structure of it.

Talk from J. Hewett

New Physics Parameter Space

Mass

LHC

~ TeV

B-Physics

Tools for Probing New Physics Consistency among angles & sides of U.T., Bs-Mixing, K physics Comparison of CP Violation in different channels

sin 2 via B Ks, Ks, ’Ks, K+K-Ks

sin 2 via Bd DK, Bs DsK

Rare ProcessesDecays B Xs/d, Xs/dll, l+l-, Xs

AFB in B Xsll

CP Asymmetries in B Xs/d, Xs/dll

D-Mixing

Standard Model Zeros Patterns of distinguishing New Physics

-

A detailed example: Xs,dll No tree level in SM very

good probe of new physics Present measurements of

Branching Fractions agree with theory

Real discovery power in AFB and mll

Talk from U. Haisch

and S. Nishida

Belle

Present KEKB L=1034

02 03

04

05

08

07

06

09

10

11

L=103

5

L~1036

dt =500fb1

dt =3000fb1

SuperBabar @SLAC

(workshop starting 22nd October)

SuperBelle @KEK

(Workshop at end of September)

BTeV @ Fermilab (1011

evts/year starting 2009)

LHCb @ CERN (1012

evts/year starting 2007)

S. Willocq

N. Katayama

H. CheungM. Merk

RoundTable on future of B physics

+ G. Gomez-Ceballos for CDF/D0

Rough physics reaches  BaBar+

Belle (2007)CDF/D0 (2007)

SuperBaBar (/year)

SuperBelle (2010)

LHCb (/year)

BTeV (/year)

LumiNbb

1ab-1

2x109

3fb-1 10ab-1

2x1010

3ab-1

6x109

  1012

  1011

eff

tag

0.07900

0.3 0.039000

 3000

 1000

 1500

C

4600.15

- 46000.05

15000.09

- -

0.06   0.03     0.06

Bs - 10o - - 5o  5o

(BdDK) 20O 500 evts 2o 6o 7-8o 13o

(BsDsK) - 300evts - - 14o 8o

sin2KS) 0.2   0.07 0.1 0.2 0.12

N(Xsll) 700 500 K*ll 7k 3K 4K K*ll 4K K*ll

sin2 (J/J) -   - - 0.06 0.02

Very approximate numbers that were used to stir the discussion

RoundTable on future of B physics

e+e- and hadron colliders are complementary: Neutrals and long living particles can hardly be done at hadron colliders Bs physics cannot be done at Y(4S)

It is important that CDF proves that precision B physics can be done at hadron colliders by doing CP in oscillation analyses

Need to prove e+e- experiments will work as well as now The measurement of with BsKK is not theoretically clean (U-spin

is not conserved) Will need BsKsKs? Who?

Requests from theory division: Bs0 Bs

Knowledge of Ms and s crucial (Tevatron?)

The hope for WIN12

CKM Fitter

2012

Anything more new?

Oscillations in BXs

New physics and rare decays

90% C.L. for BR(Bs +- ) < 1.6 x 10-6 (D0) BR(Bs +- ) < 9.5x10-7 (CDF)