FCAL and Super Belle

■ Motivations

■ Requirement to improve super-Belle detector hermeticity

■ FCAL detectors and super-Belle proposal

■ Problems, questions – starting point for discussion on the proposal

Leszek Zawiejski

FCAL Collaboration Meeting , May 07, 2008, Kraków

Slides on Belle results are based on M. Różańska, M. Yamauchi, M. Hazumi prezentations

Motivations

I High precision physics which can be studied with super-Belle detector

II Test in running experiment, FCAL detectors before realisation of the ILC project

B mesonyield

B FactoryB Factory

Super BFactory

Super BFactory

KEKB

Mt. Tsukuba

Belle

Belle Experiment

1.3 million B B pairs / day

Total ~770 106 B B pairs

_

_

peak luminosity:1.71 x 1034 cm-2 s-1

world record

Beam crossing angle :22 mrad

Major achievements at Belle

Evidence for direct CP violation in B K+

Evidence for direct CP violation in B K+

Evidence for B Evidence for B

Observation of b dObservation of b d

Observation of B K(*)llObservation of B K(*)ll

Decisive confirmation ofKobayashi-Maskawa model

Belle collaboration13 countries ~400 collaboratorsAs of June 2007 # of papers : 219 # of citations: 9883

Observation of CP violation in B meson system

Observation of CP violation in B meson system

Measurements ofCP violation in B Ks, ’Ks etc.

Measurements ofCP violation in B Ks, ’Ks etc.

Discovery of X(3872)

Discovery of X(3872)

Evidence for D0 mixingEvidence for D0 mixing

Observation of direct CP violation in B

Observation of direct CP violation in B

1. P Violation in B Decays2. Fundamental SM Parameters (Complex Quark Couplings)3. Beyond the SM (BSM)4. Unanticipated New Particles

1. P Violation in B Decays2. Fundamental SM Parameters (Complex Quark Couplings)3. Beyond the SM (BSM)4. Unanticipated New Particles

Sensistive to New Sensistive to New

Pysics Pysics

Sensistive to New Sensistive to New

Pysics Pysics

O(10-

2)

O(10-4)

O(10-5)

O(10-

2)

O(10-4)

O(10-5)

b

uW

W

b c

bW

Z

s,dt

B0 D*-+B0 D*-+

B hB h

B+ + B+ +

expected decay ratesexpected

decay rates

SSmall hadronic effects;mall hadronic effects;

theoretically clean.theoretically clean.

SSmall hadronic effects;mall hadronic effects;

theoretically clean.theoretically clean.

examples of SM amplitudesexamples of

SM amplitudes

poorly known: multiple ’s in final states experimentaly difficult !poorly known: multiple ’s in final states experimentaly difficult !

Examples: B decays with missing energy - requirement to improve hermeticity of the Belle detector

Examples: B h , B+ + , Bo D*-+

(4S)

BBtagtag

KK

Two ways of Btag reconstruction:

■ Select Bsig candidate and check whether remaining particles are consistent with B decay („inclusive” Btag reconstruction)

■ Reconstruct Btag (in exclusive mode) and check whether remaining particles are consistent with Bsig („exclusive” Btag

reconstruction)

Two ways of Btag reconstruction:

■ Select Bsig candidate and check whether remaining particles are consistent with B decay („inclusive” Btag reconstruction)

■ Reconstruct Btag (in exclusive mode) and check whether remaining particles are consistent with Bsig („exclusive” Btag

reconstruction)

Btag reconstruction:

BB event

which particles belong to Bsig

kinematical constraints on Bsig

Btag reconstruction:

BB event

which particles belong to Bsig

kinematical constraints on Bsig

signature: signature: K + K +

invisibleinvisible

signature: signature: K + K +

invisibleinvisible

rreconstrueconstrucctt

BBtagtag

rreconstrueconstrucctt

BBtagtag

at B-factories:at B-factories:ee++ee-- (4S) (4S) BB BB

B decay with missing energy e.g. B+K+

B decay with missing energy e.g. B+K+

BBsigsig

Psig = - Ptag

Experimental Techniques

DAMADAMACDMSCDMS

Expected BF’s in the SM:Expected BF’s in the SM:Expected BF’s in the SM:Expected BF’s in the SM:

Bh(*)

Flavor Changing Neutral Current process: Flavor Changing Neutral Current process:

Z-mediated electroweak penguinZ-mediated electroweak penguin + + box diagrams box diagrams

Flavor Changing Neutral Current process: Flavor Changing Neutral Current process:

Z-mediated electroweak penguinZ-mediated electroweak penguin + + box diagrams box diagrams

bW

Z

s,dts,db

W W

t

b

s,d

t

Sensistive to New Physics Sensistive to New Physics

in loops, e.g.:in loops, e.g.:

bh

s,dq~

other weakly coupled other weakly coupled

particles:particles:

possible window to light dark matter, not accessible in direct searches

e.g. C. Bird et al., PRL 93, 201803 (2004)e.g. C. Bird et al., PRL 93, 201803 (2004)

7

7

6

5*

102.2)(

109.4)(

103.5)(

101.1)(

BBF

BBF

KBBF

KBBF

J. H. Jeon et al., PL B 636, 270 (2006)J. H. Jeon et al., PL B 636, 270 (2006)

SS

Bh(*) - method

hh(*) (*) = K= K*+*+,K,K*0*0,K,K++,K,K00, , ++,,00,,++,,00,,hh(*) (*) = K= K*+*+,K,K*0*0,K,K++,K,K00, , ++,,00,,++,,00,,

E = Ei - Ebeam

Mbc = E2beam-(pi)2

(4S)

BBtagtag hh(*)(*)

B candidates

788K B 788K B

(*)s1

(*)0 /D/a/ρπDBhh(*)(*) + + nothingnothinghh(*)(*) + + nothingnothing

Reconstruct Btag in hadronic mode:Reconstruct Btag in hadronic mode:

signal signature:signal signature:signal signature:signal signature:

Mbc[GeV/c2]

EEECLECL: residual energy in calorimeter

for signal: for signal: EEECLECL 0 0

EEECLECL: residual energy in calorimeter

for signal: for signal: EEECLECL 0 0

535 M535 MBBBB

MCMC

background suppression: 1.6 < p1.6 < phh(*)(*) < 2.5 GeV/c < 2.5 GeV/cbackground suppression: 1.6 < p1.6 < phh(*)(*) < 2.5 GeV/c < 2.5 GeV/c

reject 2-body (eg. BK*)reject 2-body (eg. BK*)suppress bcsuppress bc

Bh(*) - results

535 M535 MBBBB

hep-ex/0707.0138 submitted to PRL

hep-ex/0707.0138 submitted to PRL

1.6 < p* < 2.5 GeV/c1.6 < p* < 2.5 GeV/c

Nb = 20.0 4.0 Nobs = 10

BBFF(B(B++ K K++) < 1.4x10) < 1.4x10-5-5 @90% CL@90% CLBBFF(B(B++ K K++) < 1.4x10) < 1.4x10-5-5 @90% CL@90% CL

K+ momentum

signal SM BF 20

signal SM BF 20

Theoretical predictions: C. Bird et al., PRL 93, 201803 (2004)Theoretical predictions: C. Bird et al., PRL 93, 201803 (2004)

Light dark matter? Can be searchedin super-BelleB K* ( or )

Karlsruhe SUSY07 Maria Rozanska for the Belle Collaboration

14

B

b

uW

b

uH

purely leptonic B decay: purely leptonic B decay:

W-mediated annihilationW-mediated annihilation

purely leptonic B decay: purely leptonic B decay:

W-mediated annihilationW-mediated annihilation

theoretically very cleantheoretically very clean,, SM BF:SM BF:theoretically very cleantheoretically very clean,, SM BF:SM BF:

BubBm

ml

mG VfmlBBFB

lBF 2222

8 ||)1()( 2

22

B decay constantB decay constant410)40.059.1()(

BBF

fB=0.2160.022 GeV from LQCD HPQCD Collab., PRL 95, 212001 (2005)

Sensistive to Charged Sensistive to Charged

HiggsHiggs

mmbbtantan++mmcccotcot mmtantan

Decay amplitude Decay amplitude m mb b mm tantan22

22 2

2(1 tan )B

HH

mr

m

HH effects to branching fractioneffects to branching fraction: :

HSM rBBFBBF

)()(

providingproviding ffBB is known is known providingproviding ffBB is known is known

W. S. Hou, PR D 48, 2342 (1993)W. S. Hou, PR D 48, 2342 (1993)

449 M449 MBBBB

PRL 97, 251802 (2006)

PRL 97, 251802 (2006)

B - results

Constraint on Charged Higgs (2HDM II)Constraint on Charged Higgs (2HDM II)Constraint on Charged Higgs (2HDM II)Constraint on Charged Higgs (2HDM II)

excluded

40.460.51

0.560.49 101.79

))()(()( syststatBBF 40.46

0.510.560.49 101.79

))()(()( syststatBBF

taking |Vub| = (4.39 0.33)×10-3 from HFAGtaking |Vub| = (4.39 0.33)×10-3 from HFAGMeV )()( syststatfB3437

3631229

MeV )()( syststatfB

3437

3631229

0.511.13Hr 0.511.13Hr )10)40.059.1()(( 4

SMBBF )10)40.059.1()(( 4

SMBBF

22 2

2(1 tan )B

HH

mr

m

rH

BD(*)

W

b cH

b c

mmbbtantan++mmcccotcot

mmtantan

Theoretical tool:

Heavy Quark Effective Theory (HQET)

Theoretical tool:

Heavy Quark Effective Theory (HQET)

Sensitive to extended Higgs sector

New Physics at tree level

Sensitive observables e.g. polarization; possible O(1 ) effectsExpected SM BF’s~O(10-2)

inclusive BF(bc) = (2.48 0.26)% from LEPinclusive BF(bc) = (2.48 0.26)% from LEP PDG 2007PDG 2007

Y.Okada: CP violation & CKM; plenary talk at ICHEP06

H-b-u vertex measured in B

H-b-c vertex measured in B D

H-b-t vertex measured in direct production by LHC.

Y.Okada: CP violation & CKM; plenary talk at ICHEP06

H-b-u vertex measured in B

H-b-c vertex measured in B D

H-b-t vertex measured in direct production by LHC.

Forward Detector K.F Chen, C. Peng

Forward Region

K.F Chen, C. Peng

Pair Monitor

FCAL detectors – candidates for use in Belle upgrade project?

LumiCal calorimeter

The current design:

Several ( 3 ) sensor layers can be used as tracker detector?

Can an increase in granularity will be acceptable for FE electronicsdesign as was preparedrecently for ILC?

EM Si/W calorimeter with 30 layers with the following thicknesses:Tungsten - 3.5 mm Silicon sensor - 0.32 mmSupport - 0.6 mmElectronic space - 0.1 mmInner radius of the active area : 80 mmOuter radius : 195 mmSensor segmentation –64 cylinders with 48 sectors in azimuthCalorimeter can be placed 2270 mm from IP

Angular coverage from ~ 30 mrad to 80 mrad(ILD installation place)

LumiCal extension : add silicon tracker (pad/pixel layers?

(pCVD, GaAs, sCVD, radiation hard Si)

Possible places for FCAL detectors at super-Belle

The central region -Yoshuke talk

or somewhere outside the central region ?

FW 5.3 – 11.1 degree, BW 165.1 – 172.7 degree

Proposal to install FCAL detectors in super-Belle detector creates several problems and questions. Sensors&mechanics

What sensors(silicon/diamond/GaAs) granularity seems to be sufficient? How many layers? What will be optimal type of the detector: calorimeter (tungsten/sensors) and tracker (with a few layers) or only tracker (pads, pixels layers) How big energy deposit can be expected in sensors (shower, MIP’s)? What power will be distributed by FE electronics – a way of cooling Radiation dose( during for example in year operation) ? Place – how far from IP? Depends on type of the selected detector, accepted range for polar angle and background -outside the both sides of Belle detector, clamped on beam pipe? Monte Carlo (physics and detector ) studies can help to give answers for most of them

PROBLEMS - QUESTIONS

FE electronics& readout What will be occupancy? Manpower and short time is a big problem: if the FE and readout electronics (ASIC,fanout) as designed for ILD detector can be used (with small modifications) for super-Belle project.

Discussion on possible participation in super-Belle ? How useful in realization of ours ILD tasks can be experience obtained by work of FCAL detectors in super-Belle experiment ?

Which FCAL groups (worked on the corresponding detector) can really be interested? From realisation of the particular scientific tasks in Institutions working in FCAL, such group should became an official member of super- Belle collaboration

Timetable : what is exactly a death time for installation of FCAL detector (s) inside super-Belle - 2012? It will be necessary to estimate more precisely available menpower and cost.

Financial support – requested money, with help from super-Belle collaboration? Such money should cover the build the prototypes, temporary work of specialists, travel expences, staying in KEKB. The possibility to get a big money from national financial institutions (polish) are very limited.

Strategy of super-Belle collaboration

Roadmaps : KEKB

Experiment +upgrade

RDRTech, Design Phase 1

GDE process

physics

2005 2006 2007 2008 20122009 2010 2011

LHC physics

CLIC R&D

EUROTeV

TDP 2

constructioncommissioning

site selection

EUDET

and ILC

Summary

Super Belle Physics program will be very excited

An increase of the detector hermeticity help in selection rare processes

FCAL detectors (with possible modifications), can play important role in suplaying information on the missing energy (for selection the very clean sample of events)

One can expect big problems with manpower, money, short timetable for realisation, formalities how to become the official member of super Belle collaboration

Futher discussion on possibility to join the project is necessary