The B Factory Era 9 -1...ES b * m = E −pB * * ΔE =EB −Eb Kinematics: Topology: Important...
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The B Factory Era The B Factory Era ARGUS Symposium: 20 years of B meson mixing ARGUS Symposium: 20 years of B meson mixing James D. Olsen James D. Olsen Princeton University Princeton University November 9, 2007 November 9, 2007 10 9 -- B meson observed (1982) B meson observed (1982); “long long” lifetime (~1.5ps) lifetime (~1.5ps) B 0 mixing observed (1987) mixing observed (1987); V ub ub measured; lower bound on measured; lower bound on m t > 42 > 42 GeV GeV; ; V ub ub ≠ 0 0 → KM in the game as source of CPV KM in the game as source of CPV Radiative Radiative penguin penguin b b → sγ γ observed (1993) observed (1993); major major constraint on NP models constraint on NP models; asymmetric B Factory proposals ; asymmetric B Factory proposals CPV in B decays CPV in B decays observed (2001) observed (2001); sin2 ; sin2β consistent consistent with SM and constraints from existing CKM measurements with SM and constraints from existing CKM measurements The ab The ab -1 era era: precision tests of the CKM paradigm; precision tests of the CKM paradigm; constraining new physics with flavor physics constraining new physics with flavor physics Direct CPV observed (2004) Direct CPV observed (2004); confirmation of KM ; confirmation of KM mechanism; CKM parameters over mechanism; CKM parameters over-constrained constrained 10 8 -- 10 7 -- 10 4 -- 10 5 -- 10 6 -- #B’s 1999 - B Factories start operation Kobayashi Kobayashi- Maskawa Maskawa Mechanism Mechanism ( ) ( ) ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎜ ⎝ ⎛ − − − − − − − = 1 1 2 1 2 1 2 3 2 2 3 2 CKM λ η ρ λ λ λ λ η ρ λ λ λ A i A A i A V * cb cd V V * tb td V V α Length of each side ~O( Length of each side ~O(λ 3 ) * ub ud V V β γ * cb cd V V * cb cd V V ℜ ℑ ) 0 , 1 ( ) 0 , 0 ( ) , ( η ρ CP ↔ ≠ 0 η 0 * * * = + + tb td cb cd ub ud V V V V V V Length of each side ~O( Length of each side ~O(1) 22 . 0 = = us V λ CP violation with CP violation with e + e - → ϒ(4S) (4S) → BB BB BB pair produced in coherent quantum state: EPR effect BB pair produced in coherent quantum state: EPR effect ) cos( ) sin( ) ( ) ( ) ( ) ( 0 0 0 0 t m C t m S f B f B f B f B A CP CP f f CP CP CP CP CP Δ Δ − Δ Δ = → Γ + → Γ → Γ − → Γ ≡ “Indirect CPV” “Direct CPV” “Indirect CPV” “Direct CPV” B 0 B 0 Use interference between two Use interference between two indistinguishable paths to indistinguishable paths to observe CP asymmetries observe CP asymmetries ϒ(4S) (4S) e + e - ~30 ~30μm Boost the CM: Boost the CM: Δz = = βγ βγcΔt ~ 260 ~ 260μm → Asymmetric B Factories! Asymmetric B Factories! PEP PEP- II B Factory @ SLAC II B Factory @ SLAC ( ) ( ) ) (delivered fb 500 s cm 10 2 . 1 56 . 0 V; G 58 . 10 V G 1 . 3 V G 0 . 9 1 1 2 34 peak CM − − − + − = × = = = × ∫ Ldt L e E e e e e βγ (4 x design) KEK B Factory KEK B Factory ( ) ( ) (logged) fb 730 s cm 10 7 . 1 425 . 0 V; G 58 . 10 V G 5 . 3 V G 0 . 8 1 1 2 34 peak CM − − − + − = × = = = × ∫ Ldt L e E e e e e βγ World Record World Record
Transcript of The B Factory Era 9 -1...ES b * m = E −pB * * ΔE =EB −Eb Kinematics: Topology: Important...
The B Factory EraThe B Factory EraARGUS Symposium: 20 years of B meson mixingARGUS Symposium: 20 years of B meson mixing
James D. OlsenJames D. OlsenPrinceton UniversityPrinceton UniversityNovember 9, 2007November 9, 2007
109--
B meson observed (1982)B meson observed (1982);; “longlong”” lifetime (~1.5ps)lifetime (~1.5ps)
BB00 mixing observed (1987)mixing observed (1987); VVubub measured; lower bound on measured; lower bound on mmtt > 42 > 42 GeVGeV; ; VVubub ≠≠ 0 0 →→ KM in the game as source of CPVKM in the game as source of CPV
RadiativeRadiative penguinpenguin b b →→ ssγγ observed (1993)observed (1993);; major major constraint on NP modelsconstraint on NP models; asymmetric B Factory proposals; asymmetric B Factory proposals
CPV in B decaysCPV in B decays observed (2001)observed (2001); sin2; sin2ββ consistent consistent with SM and constraints from existing CKM measurementswith SM and constraints from existing CKM measurements
The abThe ab--11 eraera:: precision tests of the CKM paradigm; precision tests of the CKM paradigm; constraining new physics with flavor physicsconstraining new physics with flavor physics
Direct CPV observed (2004)Direct CPV observed (2004); confirmation of KM ; confirmation of KM mechanism; CKM parameters overmechanism; CKM parameters over--constrainedconstrained
108--
107--
104--
105--
106--
##BB’’ss 1999 - B Factories start operation
KobayashiKobayashi--MaskawaMaskawa MechanismMechanism
( )
( )⎟⎟⎟⎟⎟⎟⎟
⎠
⎞
⎜⎜⎜⎜⎜⎜⎜
⎝
⎛
−−−
−−
−−
=
112
1
21
23
22
32
CKM
ληρλ
λλλ
ηρλλλ
AiA
A
iA
V
*cbcdVV
*tbtdVVα
Length of each side ~O(Length of each side ~O(λλ33))
*ubudVV
βγ
*cbcdVV *
cbcdVV
ℜℜ
ℑℑ
)0,1()0,0(
),( ηρ
CP ↔≠ 0η
0*** =++ tbtdcbcdubud VVVVVV
Length of each side ~O(Length of each side ~O(11))
22.0== usVλ
CP violation with CP violation with ee++ee-- →→ ϒϒ(4S) (4S) →→ BBBBBB pair produced in coherent quantum state: EPR effectBB pair produced in coherent quantum state: EPR effect
)cos()sin()()()()(
00
00
tmCtmSfBfBfBfBA
CPCP ff
CPCP
CPCPCP
ΔΔ−ΔΔ=→Γ+→Γ→Γ−→Γ
≡
“Indirect CPV” “Direct CPV”“Indirect CPV” “Direct CPV”
B0 B0
Use interference between two Use interference between two indistinguishable paths to indistinguishable paths to observe CP asymmetriesobserve CP asymmetries
ϒϒ(4S)(4S)ee++
ee--
~30~30μμmm
Boost the CM: Boost the CM: ΔΔzz = = βγβγccΔΔtt ~ 260~ 260μμmm→→ Asymmetric B Factories!Asymmetric B Factories!
PEPPEP--II B Factory @ SLACII B Factory @ SLAC( ) ( )
)(delivered fb500
scm102.1
56.0 V;G 58.10VG 1.3VG 0.9
1
1234peak
CM
−
−−
+−
=
×=
==×
∫ LdtL
eEeeee
βγ(4 x design)
KEK B FactoryKEK B Factory( ) ( )
(logged) fb730
scm107.1
425.0 V;G 58.10VG 5.3VG 0.8
1
1234peak
CM
−
−−
+−
=
×=
==×
∫ LdtL
eEeeee
βγ
World RecordWorld Record
Factory OperationFactory Operation
PEPPEP--II without trickle injectionII without trickle injectionPEPPEP--II II LumiLumi
HER currentHER currentLER currentLER current
Time (hours)
KEKB: 5KEKB: 5--10 min intervals10 min intervalsPEPPEP--II: 10Hz (LER), 5Hz (HER)II: 10Hz (LER), 5Hz (HER)
Time (hours)
KEKB 24hr Record: 1.243fb-1
SLAC 24hr Record: 0.911fb-1
Time (hours)
PEPPEP--II with trickle injectionII with trickle injection
Data in, physics out…Data in, physics out…
> 1200fb-1
> 550 pubs
1fb477 −
1732fb−
Physics Analysis with a Boosted Physics Analysis with a Boosted ϒϒ(4S)(4S)Instructions: 1) boost back to CMInstructions: 1) boost back to CM
2) use techniques developed by ARGUS & CLEO!2) use techniques developed by ARGUS & CLEO!
2*2bES
*BpEm −=
**bB EEE −=Δ
TopologyTopology::Kinematics:Kinematics:
Important differenceImportant differenceFor two-body decays: momentum of B daughters can be > 4 GeV/c:
1) Affects resolution in ΔE, E(γ,π0), etc
2) Higher fraction of merged π0
3) K/π separation more difficult
events spherical BB
events jetty qq Establishing the KM MechanismEstablishing the KM Mechanism
Experimental MethodExperimental Method
m180 m260 t c z
μμβγ
~σ(Δz)~Δ=Δ
0tagB
+e-e
0CPB
ϒ ϒ(4S)(4S)
zz
t = 0t = 0
ΔΔzz →→ ΔΔtt
−π 0SK
ψ/J
+π
+μ
−μ
β
α
γ
β2sin∝
Asym
met
ry
00
00
BB
BB
NNNN
A+
−=
−K
Lepton Tags: Lepton Tags: mistagmistag rate rate ≈≈ 8%8%
KaonKaon Tags:Tags:mistagmistag rate rate ≈≈ 18%18%
−ePrecision CP ViolationPrecision CP Violation
016.0035.0697.02sin ±±=βBaBar (384M)BaBar (384M)
017.0031.0642.02sin ±±=βBelle (534M)Belle (534M)
03.068.02sin WA ±=β
Is it the right answer?Is it the right answer?
Yes! Large O(1) CP violation consistent with Yes! Large O(1) CP violation consistent with a single source: a single source: phase of the CKM matrixphase of the CKM matrix
Is KM the only answer?Is KM the only answer?SuperweakSuperweak ansatzansatz: CP: CP--violating phenomena violating phenomena
arise from |arise from |ΔΔF| = 2 transitionsF| = 2 transitions
b
b
d
d
2=ΔB 1=ΔB
To disprove Superweak theories we needed to observe CP violation in decay (repeat of K system)
tcu ,, tcu ,,
No CP violation in decay
−+→ πKB0
+−→ πKB 0
Direct CP Violation in Direct CP Violation in BB00 →→ KK++ππ--
Established by BaBar and Belle in 2004Established by BaBar and Belle in 2004
BaBar + Belle + CDF + CLEO:BaBar + Belle + CDF + CLEO:
012.0097.02007WA ±−=A
δγππ
ππ sinsinAsymmetry PT
NNNN
KK
KK ∝+
−≡
−++−
−++−
weak phaseweak phase
strong phasestrong phase
γ δ
Consequences:1) Superweak2) First evidence for γ ≠ 0,π 3) Large strong phase δ
CP Violation in BCP Violation in B00 →→ ππ++ππ−−
0
100
200
300
q = +1q = −1
(a)
No
. o
f π
+π
- ev
en
ts
-1
0
1
-5 0 5Δt (ps)
π+π
- as
ym
me
try
(b)
0.0738.0
0.0886.0WA
WA
±−=
±−=
ππ
ππ
C
S
Belle + BaBar:Belle + BaBar:
Observed by Belle Observed by Belle (2004)(2004) and BaBar (2007)and BaBar (2007)
SuperweakSuperweak prediction: prediction: SSππππ = = --sin2sin2ββ (true within errors!)(true within errors!)C = 0 (not true)C = 0 (not true)
CCππππ ≠ 0 ≠ 0 →→ critical confirmation of KMcritical confirmation of KM
SU(3) prediction: SU(3) prediction:
(Indirect CPV)(Indirect CPV)
(Direct CPV)(Direct CPV)
02.034.0 ±−=ΓΓ
= πππ
πππ K
K AC
Direct CP Asymmetry MeasurementsDirect CP Asymmetry Measurements(charmless modes)(charmless modes)
OverOver--constraining CP Violationconstraining CP Violation
Measuring sin2Measuring sin2αα
b
d b
d
0B b
d
t
t d
u
ud
0B
)sin(2sin tmACP ΔΔ= α1,, aρπ
oo 3109 ±=α08.061.0WA ±−=ππS
1,, aρπ
ππS
Compare with Global CKM Fits:Compare with Global CKM Fits:
( )( )o
o
313- 102 :Fitter CKM
691 :Fit UT+
±
*cbcdVV
*tbtdVVα*
ubudVV
βγ
The problem with The problem with αα……Optimal Case: 000 ,
ππππππ ±−+<< AAAδαααππ +=∝ effeff ;2sinS
Not true for Not true for ππππ system!system!
( )%90@ 39o<Δα
Combined Results for Combined Results for αα
( )o891±=α( )o687 ±=α
Penguin “pollution” much smaller in ρρρπ Dalitz analysis removes mirror solutions
Measuring Measuring γγ
*cbcdVV
*tbtdVVα*
ubudVV
βγ
nsuppressiocolor 3 ×∝ λuA3λ∝cA
)()()()(
++−−
++−−
→Γ+→Γ→Γ−→Γ
≡DKBDKBDKBDKBACP
For illustration only
Combine all measurements!Combine all measurements!
Dalitz modelLarge stats, Dalitz info
D0(Kshh) DalitzGGSZ
Low statsLarge interf.D0(Kπ)ADS
Low stats, small interf.ConstraintsD0(CP±)GLW
Disadv.Adv.ModesMethod
δγ sinsinBr∝Can be reduced by CLEO-c!
Combined Measurements of Combined Measurements of γγ
( )o3177 ±=γ ( )o1688 ±=γ
Best method (Best method (DalitzDalitz) was invented ) was invented only inonly in 2003!2003!
Measurements of Measurements of VVubub
Inclusive Vub
Exclusive Vub
*cbcdVV
*tbtdVVα
*ubudVV
βγ
*cbcdVV
Critical KM test: Critical KM test: does sin2does sin2ββintersect the intersect the VVubub/V/Vcbcb ring?ring?
%8~σ
OverOver--constraining CP Violationconstraining CP ViolationSides Angles
All
Impact of B Factories and Impact of B Factories and TevatronTevatron
1998
Enormous progress in the past decade has led to a paradigm change: Use precision CKM measurements to search for New Physics (NP)
20072007
Constraining New Physics with Constraining New Physics with Flavor PhysicsFlavor Physics
““Tasting” New PhysicsTasting” New PhysicsStandard Model Flavor Transition Rule:Standard Model Flavor Transition Rule:
No 1st-order flavor-changing neutral currents
b s
Forbidden
s
s Suppressed
g, γ, Z0
If the new physics has a generic flavor structure, we should seeIf the new physics has a generic flavor structure, we should see large large nonnon--SM effects in decays mediated by flavorSM effects in decays mediated by flavor--changing neutral currents:changing neutral currents:
Ex. Supersymmetry
g, γ, Z0
MSSM Constraints from b MSSM Constraints from b →→ ssγγ“Most effective New Physics killer”
( ) ( ) 41026.055.3 −×±=→ γsbB
( )%6.34.0 ±=CPA
( )% 42.0 170120..-CPA
+=
( ) ( ) 41030.057.3 −×±=→ γsbB
Experiment:Experiment:
Theory:Theory:
β2sin
CP Violation in b CP Violation in b →→ s penguinss penguins
qsqbS →≈ allfor 2sin:ModelStandardtheIn
β
First observation of indirect CP violation in b → s (2006)
Sη’K = 0.61 ± 0.07
allowed region
SM
TeV! NP >>Λ
%40~<Model Standard
Physics New
Model-independent constraints from Bd mixing
Constraining NP with Flavor PhysicsConstraining NP with Flavor Physics
SM
NPSM
AAAer di
d+
≡θ22
TreesTrees
LoopsLoops
““New Physics Flavor Problem”New Physics Flavor Problem”
TeV 1~ <Λ TeV >>ΛIf new physics lives at the TeV scale it cannot have a generic flavor structure → Minimal Flavor Violation!
Model-independent constraints from Bd mixing
Testing Minimal Flavor Violation?109--
B meson observed (1982)B meson observed (1982);; “longlong”” lifetime (~1.5ps)lifetime (~1.5ps)
BB00 mixing observed (1987)mixing observed (1987); VVubub measured; lower bound on measured; lower bound on mmtt > 42 > 42 GeVGeV; ; VVubub ≠≠ 0 0 →→ KM in the game as source of CPVKM in the game as source of CPV
RadiativeRadiative penguinpenguin b b →→ ssγγ observed (1993)observed (1993);; major major constraint on NP modelsconstraint on NP models; asymmetric B Factory proposals; asymmetric B Factory proposals
CPV in B decaysCPV in B decays observed (2001)observed (2001); sin2; sin2ββ consistent consistent with SM and constraints from existing CKM measurementswith SM and constraints from existing CKM measurements
The abThe ab--11 eraera:: precision tests of the CKM paradigm; precision tests of the CKM paradigm; constraining new physics with flavor physicsconstraining new physics with flavor physics
Direct CPV observed (2004)Direct CPV observed (2004); confirmation of KM ; confirmation of KM mechanism; CKM parameters overmechanism; CKM parameters over--constrainedconstrained
108--
107--
104--
105--
106--
##BB’’ss 1999 - B Factories start operation
The Super B Factory EraThe Super B Factory Era
The Luminosity FrontierThe Luminosity Frontier1036 “Super B”
KEK
Super B Factory ProposalsSuper B Factory Proposals
““UltraUltra--high currents”high currents”
““UltraUltra--low low emittanceemittance””
1236 scm108.0 −−×=L
1236 scm100.1 −−×≥L
@ KEK
@ ~Frascati (Tor Vergata)
Y. Ohnishi
CKM in 201x?CKM in 201x?CPV in b → s penguins CKM parameters with 75ab-1
BackupBackup
History of CP Violation in BHistory of CP Violation in B00 →→ ππ++ππ−−
ππS
ππC
BaBar
Belle
BaBar
Belle
VVtdtd/V/Vtsts from b from b →→ ((s,ds,d) ) γγ
ργ/K*γ → |Vtd/Vts| = 0.200 ± 0.021 (exp) ± 0.015 (thy)mixing → |Vtd/Vts| = 0.2060 ± 0.0007 (exp) ± 0.0081 (thy)
*cbcdVV
*tbtdVVα*
ubudVV
βγ
Observation of B Observation of B →→ ργργ by Belle and BaBar by Belle and BaBar allows a complementary constraint on allows a complementary constraint on VVtdtd/V/Vtsts
(6.4σ)(5.1σ)B → (ρ,ω)γ
BaBar (347MBB)Belle (386MBB)BF x 106
10.009.0
34.031.0 32.1 +
−+− 0.08 25.1 25.0
24.0 ±+−
Beam’s eye view
x
y
0/ SCP KJB ψ→
−+μμ−+ππ
−+→ π*0tag DB
+π0D+−πK
z
Direct CP Violation in BDirect CP Violation in B00 →→ DD++DD--??b → c tree
b → d penguin
Phys. Rev. Lett. 99, 071801 (2007)Phys. Rev. Lett. 98, 221802 (2007)
SM predicts S ~ -sin2b and C ~ 0
3.23.2σσ
0B 0B
Additional Measurements of Additional Measurements of ββ
u,
The answer lies beyond the Standard Model!
0.001
0.01
0.1
1
10
100
1000
1 2 3
Generation
Mas
s (G
eV)
ds
b
u
c
t
( ) ( ) ( )btscdu mmmmmm ,,, << 1122313 <<<<<< θθθ
Known Unknowns: Mass and FlavorKnown Unknowns: Mass and Flavor
⎟⎟⎟
⎠
⎞
⎜⎜⎜
⎝
⎛
tbtstd
cbcscd
ubusud
VVVVVVVVV
.
.
CKM MatrixCKM MatrixQuark Masses
What is the origin of the quark mass and mixing hierarchies?What is the origin of the quark mass and mixing hierarchies?
Measuring Measuring VVubub and and VVcbcb
*cbcdVV
*tbtdVVα
*ubudVV
βγ
*cbcdVV
,cbV ubV
,cX uX
,cbV ubV,*D π
Inclusive Vxb Exclusive Vxb
Challenge for experiment Challenge for theory
Critical KM test: Critical KM test: does sin2does sin2ββintersect the intersect the VVubub/V/Vcbcb ring?ring?
?
Constraining NP with Flavor PhysicsConstraining NP with Flavor Physics
Standard Model Reference:Standard Model Reference:decays allowed at 1decays allowed at 1stst orderorder
Search in loopSearch in loop--dominated dominated decays for inconsistencies:decays for inconsistencies:
SM
NPSM
AAAer di
d+
≡θ22
