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Future B Physics Program at KEK
BNM 2008 (24-Jan, Atami) Y.Sakai, KEK based on slides by Masa Yamauchi, KEK
(KEKB upgrade strategy)
- KEK’s Roadmap -
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Outline
Introduction: KEKB and BelleNext program of quark flavour physicsKEK’s five year roadmapKEKB upgrade plan → Onishi’s talkDetector issuesOrganization of new experimental groupSummary
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/ KL detector
Central drift chamberHe(50%)+C2H6(50%)
EM calorimeter (CsI(Tl))
Cherenkov detector n=1.015~1.030
Si vertex detector
TOF counter
SC solenoid 1.5T
Belle DetectorBelle Detector
8GeV e
3.5GeV e
14 countries, 55 institutes, ~400 collaborators
The The BelleBelle Collaboration CollaborationThe The BelleBelle Collaboration CollaborationIHEP, ViennaITEPKanagawa U.KEKKorea U.Krakow Inst. of Nucl. Phys.Kyoto U. Kyungpook Nat’l U. EPF Lausanne Jozef Stefan Inst. / U. of Ljubljana / U. of MariborU. of Melbourne
BINPChiba U.U. of CincinnatiEwha Womans U.Fu-Jen Catholic U.U. of GiessenGyeongsang Nat’l U.Hanyang U.U. of HawaiiHiroshima Tech.IHEP, BeijingIHEP, Moscow
Nagoya U.Nara Women’s U.National Central U.National Taiwan U.National United U.Nihon Dental CollegeNiigata U.Nova GoricaOsaka U.Osaka City U.Panjab U.Peking U.Princeton U.RikenSaga U.USTC
Seoul National U.Shinshu U.Sungkyunkwan U.U. of SydneyTata InstituteToho U.Tohoku U.Tohuku Gakuin U.U. of TokyoTokyo Inst. of Tech.Tokyo Metropolitan U.Tokyo U. of Agri. and Tech.INFN TorinoToyama Nat’l CollegeVPIYonsei U.
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Scientific Achievements of B Factories (1)
Observation of CPV in the B meson system
ACP(t) =(BfCP;t) (BfCP;t)
(BfCP;t) (BfCP;t) = Af cosmt Sf sinmt
Af ~ 0Sf = 0.652±0.039±0.020
Consistent with BaBar’s meas.
B0J/KS
B0J/KS
Belle, July 05
Belle, July 05
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Achievements of the B Factories
Quantitative confirmation of the KM model
Af ~ 0Sf = 0.652±0.039±0.020
Violation of CP symmetry !
B0J/KS
B0J/KS
Belle, July 05
Belle, July 05
Discovery of CP violation in BB systemDiscovery of CP violation in BB system
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Other highlights
SMBelle, 2005
D0-D0 mixing
AFB in BK*ll
X(3872)
Many new resonances
Bdtransition
Evidence for B
and more…
Z(4430)
BD*
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Another important achievement
Success of KEKB and PEP-II enabled us to design a new ee B factory with much higher Lpeak.
Asymmetric ee collider with L > 1034
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What is next with flavour physics?
If new physics at O(1)TeV…– It is natural to assume that the effects are seen in B/D/
decays.– Flavour structure of new physics?– CP violation in new physics?– These studies will be useful to identify mechanism of SU
SY breaking, if NP=SUSY.
Otherwise…– Search for deviations from SM in flavor physics will be o
ne of the best ways to find new physics.
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KEKB upgrade
Asymmetric energy ee collider at ECM=m((4S)) to be realized by upgrading the existing KEKB collider.
Super-high luminosity 21035/cm2/sec 210 9 BB per yr.
210 9 per yr.
Higher beam current,more RF, smaller y* andcrab crossing L = 21035/cm2/sec
Belle with improved rate immunity
http://belle.kek.jp/superb/loi
final target ~81035/cm2/sec (smooth transition: 50 ab-1)
(1st stage: >x10)
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Physics at upgraded KEKB
New source ofNew source ofCP violationCP violation
New source of New source of flavor mixingflavor mixing
LFV LFV decays decays
SUSY breaking SUSY breaking mechanismmechanism
Precision test Precision test of KM schemeof KM scheme
Super-high statisticsSuper-high statisticsmeasurements:measurements:SS, sin, sin22WW, etc., etc.
Charm physicsCharm physics New resonances,New resonances, DD00DD00 mixing… mixing…
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Quark flavor changing processes
Lepton flavor violation
LHC/ILCSUSY mass spectrum
DiagonalOff-diagonal
SUSY flavour physics: mass matrix of squark and slepton will be determined by their direct production at the energy frontier and flavour physics measurements.
Y.Okada, Nov. 2007
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Present upperlimits
Measurementsat upgraded KEKB
（ ab-1 ）
Reach of presentB factories
Reach of upgradedKEKB
Dev
iatio
n fr
om S
M
Deviation from SMDeviation from SM
Relevant to baryogenesis?
Relevant to baryogenesis?
New source of CP violation
New source of CP violation
CP asymmetries of penguin dominated B decays
Searches for new sources of quark mixing and CP violation
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A possible hint for NP: b→sqq
Smaller than bccs in 7 of 9 modes
Smaller than bccs in 7 of 9 modes
Theory : tends to positive shifts
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Precise measurements of decays
LFV violating decay?
Integ. Lum. （ ab-1 ）Reach of B factories
Upgraded KEKB
Upper limits
->e
>e
T.Goto et al., 2007
New
Ph
ysi
cs p
red
icti
on
s
Bra
nchi
ng F
ract
ion
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B decays with more than one
10ab-1
Bdecays
tan cotb um m
b
u H/W
tanm
B
Search region withB decays
Provides a unique method to measure b-H±-u andb-H±-c coupling strength.
Provides a unique method to measure b-H±-u andb-H±-c coupling strength.
Interactions of H±
Belle, 2006400fb-1
Υe e
B
B
full reconstruction
0.2~0.3% for B+
D
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B decays into invisible particles?
B K(*)or_
Light dark matter can beSearched for in the upgradedKEKB.
Light dark matter can beSearched for in the upgradedKEKB.
Heavy darm matter is beingsearched for in direct detectionexperiments.
Heavy darm matter is beingsearched for in direct detectionexperiments.Model prediction
Light dark matter?
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Search for right handed interaction
CP violation in B KS 0
Pre
cisi
on o
f th
e m
easu
rem
ent
Present exp. precision
Reach of upgradedKEKB SM
Sizable CP asymmetry is expected in B0X decay, if right-handed interaction exists in new physics.
Sizable CP asymmetry is expected in B0X decay, if right-handed interaction exists in new physics.
Left-right summetry in new physics?
U-KEKB
T.Goto et al., 2007
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New resonances
c’ & e+e-ccccD0*0 & D1*0
X(3872)
c* baryon triplet
X(3940), Y(3940)c2’
Y(4660) Y(4008)
DsJ(2700)cx(3090)
Z(4430)
DsJ(2317/2460)
DsJ(2860)
Y(4260)
Y(4320)
New resonances found at Belle/BaBar
Among them X （ 3872 ） andZ （ 4430 ） are considered to be“exotic” states.
Among them X （ 3872 ） andZ （ 4430 ） are considered to be“exotic” states.
More and more exotic states will beObserved by the upgraded KEKB.
More and more exotic states will beObserved by the upgraded KEKB.
More than 10 new resonanceshave been found at B factories
More than 10 new resonanceshave been found at B factories
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Identification of SUSY breaking scenario
Bd- unitarity
m(Bs) B->Ks B->Ms indirect CP
b->s direct CP
mSUGRA- - - - - +
SU(5)SUSY GUT + R
(degenerate)
- + + - + -
SU(5)SUSY GUT + R
(non-degenerate)
- - + ++ ++ +
U(2) Flavor symmetry + + + ++ ++ ++
++: Large, +: sizable, -: small
Observ-ables
SUSYmodels
Pattern of deviations from the Standard Model Y.Okada
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Strong competitors
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Comparison with LHCb
ee is advantageous in… LHCb is advantageous in…
CPV in B→KS, ’KS,…
CPV in B→KS0
B→K, , D(*)
Inclusive b→s, see
→ and other LFV
D0D0 mixing
CPV in B→JKS
Time dependent measurements of BS
Bc and bottomed baryons
Most of B decays not including or
B(s,d)→
These are complementary to each other !!
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Roadmap -HEP-
• According to the JAHEP community’s master plan,– Highest priority is given to ILC– Before ILC, promote flavor physics at KEKB and J-PARC
• Action before the ILC approval– ILC R&D– Completion/commissioning of J-PARC
• Considering the world competition, it is urgent to improve neutrino intensity
– Continuation of KEKB/Belle with upgrade
Energy Frontier
ILC R&D Construction Experiment
LHC
Flavor Physics at Luminosity/Intensity Frontier, K, ,... at J-PARC
b, c, ,... with upgraded- KEKB/Belle
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(5 Year Plan)
KEK Web page
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KEK Roadmap : KEKB
First 3 years: shutdown• Replace beam pipe (with ante-chamber)• Upgrade interaction region• Upgrade ground level RF facility• Improve crab cavities
Last 2 years: operation & improvements
• Installation of Damping Ring• Installation of additional RF• Reinforcement of cooling facility Onishi’s talk
1st goal: 2 x 1035cm-2sec-1 smooth transition feasible to 8 x 1035cm-2sec-1(50ab-1)
1st goal: 2 x 1035cm-2sec-1 smooth transition feasible to 8 x 1035cm-2sec-1(50ab-1)
fundamentalpart
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KEK Roadmap: Belle Upgrade
- low p identification s recon. eff.- hermeticity “reconstruction”
- radiation damage and occupancy- fake hits and pile-up noise in the EM
- higher rate trigger, DAQ and computing
Issues Higher background ( 20)
Higher event rate ( 10)
Require special features
Possible solution: Replace inner layers of the vertex detector with a silicon striplet detector. Replace inner part of the central tracker with a silicon strip detector. Better particle identification device Replace endcap calorimeter by pure CsI. Faster readout electronics and computing system.
Possible solution: Replace inner layers of the vertex detector with a silicon striplet detector. Replace inner part of the central tracker with a silicon strip detector. Better particle identification device Replace endcap calorimeter by pure CsI. Faster readout electronics and computing system.
in 3 years shutdown
Belle detector upgrade
New Dead time free readout and high speed
computing systems
Faster calorimeter with Wave sampling and pure CsI crystal Super particle identifier with
precise Cherenkov device
Si vertex detector withhigh background
tolerance
Background tolerant super small celltracking detector
KL/ detectionwith scintillator
and new generationphoton sensors
New ideas are welcomed !
New experimental group
It will be practical to build new detector by upgrading existing Belle.
However, the experimental group will be a new group, not an extension of the present Belle collaboration.
New participants are all welcomed and have equal opportunities to work on detector construction and physics.
It is welcomed to join the new group, but not Belle.
Interim Steering Committee is being formed. First meeting is scheduled March 2008, inviting potential new collaborators.
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2007 2008 2009 2010
Experiment at KEKB
4 71 10 414 71 104 71 104 71 1010
2011 2012
KEKB/Belle upgrade
DetectorStudy Report(March 08)
Final detectordesign(April 09)
Pre kick-offmeeting(19,20 March 08)
2007 2008 20094 71 1 42 1010 3 5 8 9 11 12 2 311 12 6
Detector proposals Internal review
TDR
BNM(January 08)
One-day general meeting and an IB meeting at every BGM
Meeting plan
Actions to invite new collaborators
Kick-offmeeting(3,4 July 08)
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Summary
KEKB/Belle and PEP-II/BaBar have been running very successfully, and brought important scientific and technical achievements.
Next generation ee B factory with L~1036 will be very useful to study the new sources of flavor mixing and CP violation.– Search for new CPV in bs transition – Very precise test of CKM scheme– Search for lepton flavor violating decays– Studies of H± interactions with fermions– Very precise measurements of S(@10GeV), sin2W(@10GeV)…
KEK Roadmap includes KEKB upgrade. KEKB machine upgrade plan Onishi’s talk Detector upgrade necessary to improve BKG/rate immunity. New collaboration to be formed soon.
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Roadmap: comment
Our final goal of the integrated luminosity is 50/ab in the new experiment at the upgraded KEKB. However, we did not include the full upgrade of the machine in the KEK's roadmap, due to the financial constraint in the lab. We will upgrade the fundamental part of the accelerator in the first three years, followed by incremental installation of the RF systems over several years to increase the beam current and the luminosity. The initial goal, 10/ab, will be achieved in the five years of operation after resuming the experiment. It should be noted that the plan up to this point is included in the KEK's roadmap. Then, considering the results of this experiment and LHC as well as progress of ILC and others carefully, we will decide if we propose further installation of the RF system to achieve the final goal, 50/ab, in the next five years.
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Precision test of KM scheme
M.PieriniCKM2006
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Search for new flavor mixing
?b quark s quark
l l : Probe the flavor changing
process with the “EW probe”.
Theoretical predictions for ll forward-backward charge asymmetry for SM and SUSY model with various parameter sets.
, Z0
The F/B asymmetry is a consequence of -Z0 interference.
This measurement is especially sensitive to new physics such as SUSY, heavy Higgs and extra dim.
Ratio of branching fractions Branching fraction CP asymmetry q 2 distribution Isospin asymmetry Triple product correlation Forward backward asymmetry Forward backward CP asymmetry
Possible observables:
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Search for new CP phases
In general, new physics contains new sources of flavor mixing and CP violation.
In SUSY models, for example, SUSY particles contribute to the bs transition, and their CP phases change CPV observed in BK, ’K etc.
SM SUSY contribution
In general, if SUSY is present, the s-quarkmixing matrix contains complex phases justas in the Kobayashi-Maskawa matrix.
U-KEKB
T.Goto et al., 2007
Background & TRG rate in futureBackground & TRG rate in future
KEKB SuperB
Luminosity(1034cm-2sec-1)
~1.7 ~50
HER curr. (A)
LER curr. (A)vacuum (10-7Pa)
1.2
1.6
~1.5
4.1
9.4
5
Bkg increase - x 20
TRG rate (kHz)phys. origin
Bkg origin
0.40.2
0.2
1410
4Shynchrotoron radiationBeam-gas scattering (inc. intra-beam scattering)Radiative Bhabha
SVD CDC PID / ECL KLM
KEKBBkg
x10 Bkg
x20 Bkg
