New Physics and Rare B Decays

• New Physics in Loops (Motivation) • bs Penguins (2 or 3 examples)• Decays with “Large Missing Energy”• How the Super B Factory fits in

Tom Browder (University of Hawaii)

Apologies: Will aim at HEP physicists in other subfields. “If I could remember all the decay modes I would have been a botanist”

Only a small subset of possible topics from Belle and BaBar are covered; a few of the results are ~ 1year old.

New Physics

Are there new particles beyond those in the SM, which have different couplings (either in magnitude or in phase) ?

Supersymmety is an example (~40 new phases)

How to find New Physics Phases

Example:Vts: no KM phase

SM: sin21 = sin21 from BJ/ K0 (bc c s)

unless there are other, non-SM particles in the loop

eff

Vtd

Vtd

+

1

B B

, ’,

1

, ’,

_

*

*

How New Physics may enter in bs

0SK

0B

b

s

s

sd d

0SK

0B

b

s

s

sd d

Many new phases are possible in

SUSY

New physics in loops?

Extra dimensions (by Randall + Sundrum)

New Kaluza-Klein (K.K) particles are associated with the extra dimension.

(“Tower of states”)

Some may induce new phases and flavor-changing neutral currents.

e.g. K.Agashe, G. Perez, A. Soni, PRD 71, 016002 (2005)

Model: K.K. Gluon near 3 TeV

RS1

SM

++CPV in D decay

e.g. G. Burdman, Phys Lett B 590, 86 (2004)

Belle 2006: tCPV in B0 K0

“sin21” = 0.50 0.21(stat) 0.06(syst) “sin21” = 0.50 0.21(stat) 0.06(syst)

KS and KL combined background subtracted good tags t –t for KL

t distributions and asymmetry

_535M BB

Consistent with the SM (~1lower) Consistent with Belle 2005

(Belle2005: “sin21” = +0.44

Consistent with the SM (~1lower) Consistent with Belle 2005

(Belle2005: “sin21” = +0.44

unbinned fitSM

hep-ex/0608039, PRL 98, 031802(2007)

hep-ex/0608039, PRL 98, 031802(2007)

a.k.a sin(2β)

K0: sin2eff = +0.12 ± 0.31(stat) ± 0.10 (syst)K0: sin2eff = +0.12 ± 0.31(stat) ± 0.10 (syst)

BaBar: K0 using B0 K0

measurement (not sin2)

[hep-ex/0607112] _347M BB

a.k.a. sin(2 φ1)

unbinned fitSM

“sin21” = 0.64 0.10 0.04“sin21” = 0.64 0.10 0.04

535M BB 5.65.6

’K0

“sin21” = 0.58 0.10 0.03 “sin21” = 0.58 0.10 0.03

>5>5

’Ks ’KL

_347M BB

[hep-ex/0608039]PRL 98,031802(2007) [hep-ex/0607100], PRL+Sept 28 press conf

1st Observation of tCPV in a bs mode

2006: Hints of NP in b s Penguins ?

Smaller than bccs in all of 9 modes

Smaller than bccs in all of 9 modes

Theory predicts positive shifts

Naïve average of all b s modes

sin2eff = 0.52 ± 0.052.6 deviation from SM

Naïve average of all b s modes

sin2eff = 0.52 ± 0.052.6 deviation from SM

Results on Radiative and Electroweak Penguins

Example discussed here: modifications to the rate for bs γ

Measurement of inclusive b s

Measure primary only:monochromatic E spectrum

Important to measure low E to reduce model dependence

Huge Background (semi-log) experimental challenge

Background suppression• continuum: event shape• veto

Nakao

NNLO calculation

(29826) x 10-6

M. Misiak et al, hep-ph/0609232, PRL 98,022002(2007)

Theory News

Error on BF

Central value of BF

95% CL lower limit on charged Higgs mass from exp and NNLO

M. Misiak et al, hep-ph/0609232, PRL 98,022002 (2007)

Right-handed currents in b s

• tCPV in B0 (Ks0)K*

– SM: is polarized, the final state almost flavor-specific.

S(Ks0 ~ 2ms/mbsin21

– mheavy/mb enhancement for right-handed currents in many new physics

models

e.g. LRSM, SUSY, Randall-Sundrum (warped extra dimension) model

– LRSM: SU(2)LSU(2)RU(1)

• Right-handed amplitude mt/mb : is WL-WR mixing parameter

• for present exp. bounds (WR mass > 1.4TeV)

|S(Ks0 ~ is allowed.

– No need for a new CPV phase

b

b

Ls

Rs

mb

mb

msms

D.Atwood, M.Gronau, A.Soni, PRL79, 185 (1997)D.Atwood, T.Gershon, M.H, A.Soni, PRD71, 076003 (2005)

Photon polarization measurementvia time dependent CPV !

Photon polarization measurementvia time dependent CPV !

_232M BB

Status of B KS 0γ tCPV Status of B KS 0γ tCPV

Yield = 176+/- 18

535M BB M(Ks 0) < 1.8 GeV

(C)hep-ex/0608017, PRD-RC 74, 111014(2006)hep-ex/0608017, PRD-RC 74, 111014(2006)

No new physics but errors on S are large

Rare Decays with Large “Missing Energy”

Motivation for B++ν

Sensitivity to new physics from charged Higgs if the B decay constant is known

The B meson decay constant, determined by the B wavefunction at the origin

Why measuring νis non-trivial

(4S)B- B+

e+

e

B++, +e+e

B-X

The experimental signature is rather difficult: B decays to a single charged track + nothing

Most of the sensitivity is from tau modes with 1-prong

Example of a B ν candidate

Tag: BD0 ,

D0 K

Very difficult or impossible at a hadron collider

Evidence for B+ ν (Belle)

Find signal events from a fit to a sample of 54 events.

4.6 stat. significance w/o systematics,

449 106 B pairs BtagD(*)[,a1,Ds(*)] 680k tags, 55% pure. 5

decay modes

5.34.717.2

MC studies show there is a small peaking bkg in the 0 and modes.

After including systematics (dominated by bkg), the significance decreases to 3.5σ

Extra Calorimeter Energy

B+ ν (BaBar preliminary)

Awaiting BaBar’s analysis with hadronic tags

Direct experimental determination of fB • Product of B meson decay constant fB and CKM

matrix element |Vub|

• Using |Vub| = (4.39 0.33)×10-3 from HFAG

fB = 216 22 MeV (an unquenched lattice calc.)

[HPQCD, Phys. Rev. Lett. 95, 212001 (2005) ]

36 3431 37229Bf MeV

( Belle)

1.6 1.3 41.4 1.4(10.1 ) 10B ubf V GeV

Theory:

(PRL 97, 251802 (2006))

Constraints on charged Higgs mass

rH=1.130.51

Use known fB and |Vub |

Ratio to the SM BF.2

2 22

(1 tan )BH

H

mr

m

excluded

excl

uded

449M

Compare to direct searches for H+

B K(*) : Motivation

b s with 2 neutrinos

SM: B(BK* ) ~1.3 x 10-5 B (BK ) ~4 x 10-6 (Buchalla, Hiller, Isidori)

PRD 63, 014015

DAMA NaI 3Region

CDMS 04

CDMS 05

No sensitivity to M<10 GeV in direct searches

• New Physics in Loop• Light Dark Matter (M~1GeV)

_

_

_

B0 K*0 : Belle (preliminary)

_

535M BB

Exp. technique similar to B

Full-rec. tag & K + nothingFull-rec. tag & K + nothing

3.12.64.7Yield

(1.7σ stat. significance)

Sideband = 19MC expectation = 18.73.3

460K tags

[hep-ex/0608047]

Super B Factory LOI: 5σ observation of BK will be possible with 50 ab-1

SM

Comments on Super B Factories

Recent Developments for the Super B Factory Accelerator

SuperKEKB design luminosity is now 8 x 1035/cm2/sec

Low emittance/ILC inspired INFN/SLAC design is ~10 x 1035/cm2/sec

To address the full array of new physics searches, require ~50 ab-1 of integrated luminosity

c.f. Current KEKB luminosity is 1.7 x 1034/cm2 /sec

c.f. Current KEKB integrated lumi 0.6 ab-1

Interaction RegionCrab crossing

=30mrad.y*=3mm

New QCS

Super B Factory at KEK

Linac upgrade

More RF power

Damping ring

New Beam pipe

Ante-chamber & solenoid coilsto reduce photo-electron clouds

L = 81035/cm2 /sec

Question: 12 nanometer beam spot in y, 2.7 microns in x. Is this possible in a real 2-3 km circumference multi-orbit machine ?

Conceptual Design Report will be submitted to INFN soon.

First step towards Super B: Crab crossing

. Superconducting crab cavities (1 LER and 1 HER) have been installed and now are being tested at KEKB.

Backup Slides

The Super B Factory is part of a Unified and Unbiased Attack on New Physics

Newphysics

Quark sectorLepton sectorPr

opag

ator

s

expts accel, reactor,g-2, e, etc.

Super B Factory, LHCb, Rare K expts, BESIII…

LHC, ILC

mass and mixing,CPV, and LFV

Higgs boson massand couplings. New particle searches

Flavor mixing,CPV phases

LFV, CPV

Are there New Physics Phases and New sources of CP Violation Beyond the SM ?

Are there right-handed currents ?

Are there new flavor changing neutral currents ?

Are there new operators with quarks enhanced by New Physics ?

Fundamental Questions in Flavor Physics

Experiments: bs CPV, compare CPV angles from tree and loops

Experiments: AFB(BK*l l), BK rates and asymmetries

Experiments: bs CPV, B->VPγ or BV V triple-product asymmetries

Experiments: bs ννbar, D-Dbar CPV+mixing+rare, τγ

These questions can only be answered at a Super B Factory.

Why three generations ?

String Theory ? (e.g. P.Binetruy et.al.,

hep-th/0509157; J.Phys G.32: 129 (2006)); Larger Symmetry Groups ?

Experiments with quarks or heavy leptons?

This question is probably too hard – more tractable questions…..

Lessons of History New Physics is usually discovered first in loop

processes, which involve high mass virtual particles. (Heisenberg Uncertainty Principle)

Beautiful and precise measurements of the top quark mass at the Tevatron. However, the couplings |Vts|, |Vtd,| and most importantly the phase of (Vtd) cannot be measured in direct top production.

Example I: Absence of KL allowed theorists to deduce the existence of the charm quark. The rate of K mixing allowed a rough determination of the charm mass.

Example II: The absence of bs decays and the long B lifetime ruled out topless models. Large Bd mixing showed the top was heavy contrary to theory prejudices of the time. Radiative corrections from Z measurements determined the rough range of the top mass.

Vtd

Vtd

http://www.jahep.org/hec/doc/jahep_tenbou_eng_final.pdf

....

(An excerpt)

“Dai-repoton keikaku”

K. Oide (Leading Japanese Accelerator Physicist)

Official Announcement from KEK director A. Suzuki on Super B expected in 2007

Budget of Japanese

accelerator physicists

As in bs γ, heavy particles in the loops can be replaced with NP particles (e.g.W+ H+)

The Hunt for the EW Penguin:BXs l+ l-

Note contributions from virtual γ* , W, Z*

and internal t quark.

Discovered by CLEO in 1994

B → XB → Xsγ from a sum of 38 exclusive decay modes

Eγ>1.9 GeV

hep-ex/0508004, 88.9 MBB

b s : Belle result140fb-1Efficiency corrected spectrum

E >1.8 GeV (cover 95.2%)

B(B s ) = (3.55 0.32 ) x10-4 +0.30 +0.11

0.31 0.07(Stat) (sys) (theo)

<E> = 2.292 0.0260.034 GeV

<E> <E> = 0.0311 0.0730.063 GeV

[hep-ex/0403004, PRL xxx]

Moments:

useful for Vcb,Vub

An update with much more data (x 3) is in progress

SuperKEKB Projection for B Ks0 and other b smodes

Possible deviationO(1): Warped extra dim.O(1): L-R symmetric modelO(0.1): SUSY SU(5)

B K0, ’K0, KsKsKs projection for SuperKEKB

total errors(incl. systematicerrors)

“Golden” mode:K0

• Obtain CP parameters for 2-body and 3-body modes simultaneously by time-dependent Dalitz fit

KKKS

KKKS

KKKL

1516 65 KKK0signal

1516 65 KKK0signal

[hep-ex/0607112]

B0 K0 Dalitz tCPV B0 K0 Dalitz tCPV

M

_347M BB

b s : Bkg subtraction

Continuum use OFF-resonance data (ECM 60 MeV lower)

B background B X: measured by data include in MC

backup

B K(*) : Motivation

b s with 2 neutrinos

SM: B(BK* ) ~1.3 x 10-5 B (BK ) ~4 x 10-6 (Buchalla, Hiller, Isidori)

PRD 63, 014015

No sensitivity in direct searches

• New Physics in Loop• Light Dark Matter (M~1GeV)

_

_

_

The Super B Factory will face tough competition from LHCb, which is now a real experiment.

LHCb

There is considerable complementarity: photon, neutral detection and inclusive channels are considerable easier at the Super B Factory while time-dependent Bs studies are superior at LHCb.

J. Libby

10 fb-1 for LHCb

50 fb-1 for SuperB