h.evans columbia colloquium: 18-oct-04 1 the b-quark a vertex of new physics hal evanscolumbia u

H.Evans Columbia Colloquium: 18-Oct-04 1

The b-Quarka Vertex of New Physics

The b-Quarka Vertex of New Physics

Hal Evans Columbia U.


What You’re In For…What You’re In For…

1. Overthrowing the Standard Model

2. The Revolutionary b-Quark and Its Role

3. Bs Mixing at DØ – The Next Campaign

4. What’s Coming in the Grand Flavor Plan


Standing on Solid GroundStanding on Solid Ground

LEP EW-WG

H?H?


If it ain’t Broke – Fix It !If it ain’t Broke – Fix It !

Why Look Beyond the SM ?

Has (at least) 19 arbitrary parameters

Does not include Gravity Why Mpl >> MEW?

Higgs Mass not stable to radiative corrections

~ Mplanck for no new phys Mh < 800 GeV

tuning to 10-16

No Motivation for EW Symmetry Breaking

222

20

2

4 hhh MM~M


Where Should We Look ?Where Should We Look ?

Start with the BIG Questions1. Why is there Mass ? EW Symmetry Breaking

2. Antimatter ? Weak vs Mass States & CPV

3. What about Matter ? understanding QCD

Ask Them in the Right Way Look in New Places higher E, sparse meas More Precision new techniques

EW Symmetry Breaking ! turns out to be related to question 2) as well


News Flash 2008 !News Flash 2008 !

ATLASttH productionM(H) = 100 GeV

but What Now ?but What Now ?

Science all the news that’s yet to print

The Nu York Times

Elusive Higgs Boson Discovered

By THE FREE ASSOCIATION PRESS

The scientific community was rocked yesterday when the ATLAS collaboration announced the discovery of the long-sought Higgs boson in a press conference at CERN. “This is an historic occasion, and it’s all because of the work of the Columbia University group”, said Peter Higgs, the physicist after whom the particle is named…


Lots of IdeasLots of IdeasThere are lots of Ideas… Dynamical Symmetry Breaking

Technicolor: running, walking, limping…

Supersymmetry (SUSY) GMSSM, SUGRA, R-Parity

Violating

Large Extra Dimensions testable string theory!

pp ff

pp VV

• monojets

• single VB

• f,VB-pairs

SuperpartnersStandard Model

½1

½0

½1

0½

0½

0½

SSparticleSParticle

RL q,q

RL ,

L

,Z,W 0

H,A,H,h 000

g

RL q~,q~

RL

~,~

L~

21~,~

04

03

02

01

~,~,~,~

g~

MSSM: M(h) < 135 GeV !!!

Most predict something very similar to the Higgs

Distinguish using input from many sources etc., etc., etc….


The Symmetry–Flavor ConnectionThe Symmetry–Flavor Connection

The SM has a Lovely Plan for EW Sym Break & Mass

SM Symmetries & Yukawa Couplings Quark Mixing

Mixing (CKM) Matrix: Vij

EW Sym Breaking Observed Flavor Structure

.]c.hUQyDQyELy[L jR

iL

uij

jR

iL

dij

jR

iL

familyj,i

eijY

diagonal-non s,comp' imag.

diagonal real, )convention (by

dij

uij

eij

y

y,y

i j,i

jRij

iL

dj

iR

iL

uiY .]c.hDVQy[]c.hU~Qy[L

b u

W-

2ubgVFamily Changing

Decays Mixing

s

t

t

s

b

b

WW0sB 0

sB


Mixed Up QuarksMixed Up Quarks

Quark Weak Mass Eigenstates CKM Mixing Matrix 3 angles 1 complex phase CP-violation Obs. CPV requires m(qi) ≠ m(qj)

Wolfenstein Parameterization A = 0.801 ± 0.025 = 0.2265 ± 0.0024 = 0.189 ± 0.079 = 0.358 ± 0.044

Strength of CPV J = A2 6 ~ (710-5)

1121

1

21

1

23

22

32

A)i(A

A

)i(A

b

s

d

VVV

VVV

VVV

'b

's

'd

tbtstd

cbcscd

ubusud

Wea

k

Mas

s

CKMFitter Group: hep-ph/0406184

very different hierarchy than Lepton Mixing Matrix


Why is Flavor Promising (1)Why is Flavor Promising (1)

The SM has a very Specific Flavor Sector:Only one Higgs Doublet

1. FCNC’s suppressed

2. Universal Charged Current

3. VCKM is Unitary

4. 1 Parameter describes strength of all CP Violation


Getting to Know the BGetting to Know the B

Weakly Decaying B Hadrons

Large Mass Many Decays >100 observed for Bd

small QCD corr’s to pred’s

Long Lifetime (B) ~ 4 (D) ~ 5 () flight lengths O(1mm) at

colliders exp’s

Neutral B-Mesons Mix 1987: obs by ARGUS & UA1 predict heavy top 8 years before direct obs.

md ~ 0.5 ps-1 ; ms > 15 ps-1

c.f. mK ~ 0.005 ps-1

s/s < 0.3 c.f. K/K ~ 1

B-Hadrons exhibit large CPV structure of CKM matrix

Hadron Mass [MeV] Life [ps]

5279 1.67

5279 1.54

5370 1.46

6400 0.5

5624 1.23

u)b( B

d)b( B0d

s)b( B0s

c)b( Bc

(bdu) 0b

s

t

t

s

b

b

WW0sB 0

sB


The Beautiful TriangleThe Beautiful Triangle

Unitarity of VCKM 6 triangles:

one has all sides ~ equal

Angles CPV in B0 ,,,, CPV in B0 J/

K0,,’ CPV in B0 ,,’ K0

CPV in B± D0 K±

CPV in B0 D(*)+ -

Sides Ru B.R.(B Xc,u lv)

Rt Bd Mixing

Other , CPV in K0 system

K+ + v v K0 0 v v N.P. Bd,s +- , +- Xd,s

0 *tdtb

*cdcb

*udub VVVVVV

(0,1)

(0,0)

(,)

*

ubud

*tbtd

VVVV

arg

t*cbcd

*tbtd R

VV

VV

*

tbtd

*cbcd

VVVV

arg

*

cbcd

*ubud

VVVV

arg

*cbcd

*ubud

u VV

VVR

Unitarity Triangle


Putting Things TogetherPutting Things Together

Param Mode Meas

sin 2 0.726 ± 0.037

0.39 ± 0.10

(100 ± 10)o

Acp(BD(*)K) (77 ± 25)o

|Vcb| x 103 BD(*)/Xc lv 41.4 ± 2.1

|Vub| x 103 BXu lv 4.66 ± 0.43

|K| x 103 KL, KS 2.282 ± 0.017

md (ps-1) Bd mixing 0.502 ± 0.007

ms (ps-1) Bs mixing > 14.5

s)cc(b cpA

s)qq(b cpA

d)uu(b cpA

CKMFitter – ICHEP 04HFAG summer 2004

SM Fit Probability ~ 70%

CKM Phase probably the dominant source of CPV in FC processes

(damn !)CKMFittersummer 01


Why is Flavor Promising (2)Why is Flavor Promising (2) CKM Phase as only Quark-Sector CPV is ODD

most Models beyond SM lots of new CPV phases 43 in generic SUSY models !

FCNCs are also generally large Beyond the SM

Flavor Physics is Already a Major Constraint on Physics Beyond SM Note that the 3rd Family is the least well constrained

What’s Left Then? (some examples) Minimal Flavor Violation GMSB, univ.E.D.

only source of FV is in Yukawa couplings New Sources of CPV R.-S. w/ bulk q’s

FV parts have to be suppressed by e.g. heavy mass scales

Both can Modified Coupling Strengths enhanced rare decays

General Scheme different models predict different relationships b/w observables

c.f. sin 2 in B J/ Ks vs. B Ks


Natural Habitats of the b-QuarkNatural Habitats of the b-Quark

Q

Q

p

p

Incoming Particles

HardInteract

OutgoingParticles

p

e

e+

e-

ij

ij

ij

Machine √s (TeV)

(bb) (b)

Rate (Hz)

<L>(mm)

B’s

LHC 14 500 25000 1.5 all

Tevatron 1.96 100 600 0.5 all

HERA 0.32 ~0.010 > 0.1 all

LEP, SLC

0.09-0.20

0.007 0.07 3 all

B-Fact 0.01 0.001 10 0.3 Bd, B+

p –

p(b

ar)

e –

pe+

– e

-


Fermilab & Flavor PhysicsFermilab & Flavor PhysicsHistory

Commissioned 1967 Tevatron (p-pbar) 1983 Main Injector 1999 Run II Start 2001

Some Highlights b-quark discovery: 1977

Lederman, et al t-quark discovery: 1994

CDF & DØ

discovery: 2000 DONUT


The Tevatron ColliderThe Tevatron ColliderWorld’s Highest E Accelerator

proton – antiproton collisions ~4 miles circumference >1000 supercond. magnets

Main Injector(new)

Tevatron

DØCDF

Chicago

p source

BoosterIb

92-96

IIa (now)

IIb

(goal)

E-CM [GeV] 1800 1960 1960

Bunches 6x6 36x36 36x36

Spacing [ns] 3500 396 396

p/bch (x1010) 23 22 27

Anti-p/bch (x1010) 5.5 2.2 13

Peak Lumi. (x1031)

[cm-2s-1] 0.16 10 28

Lumi/week pb-1 3.2 8 55

Tot Lumi fb-1 0.125 0.59 9

Int’s/X’ing 2.5 ~1 >6


DØ CollaborationDØ Collaboration

650 people84 institutions19 countries

DØ

Co

llabo

ration

Meetin

g: Ju

ne 2003, B

eaun

e, Fran

ce


Data Collected & AnticipatedData Collected & Anticipated

Run II Data so Far Apr 2001 start of Run

II Apr 2002 DØ fully

commiss. 470 pb-1 collected to now 200 – 250 pb-1 analyzed

Run II Projections (June 04) inst. lumi. 2.8x1032 cm-2s-1

total data 4 – 9 fb-1

DØ upgrade: summer 05

current peak L

install upgrades


DØ Detector (the cartoon)DØ Detector (the cartoon)Central Scintillator

Forward Mini-drift chamb’s

Forward Scint

Shielding

Tracking: Solenoid(2T), Silicon,FiberTracker,Preshowers

New Electronics,Trigger,DAQ

Calorimeter

Central PDTs


The Real McCoy !The Real McCoy !

• ~1M Channels

• 2.5M Event/s

• 250 KB/Event


DØ à la carteDØ à la carte

DØ is a General Purpose DetectorDesigned to Study a Huge Range of Physics Topics

QCD Understand the strong force where it is predictive Background for all other physics

B Physics QCD at perturb/non-perturb interface Probe quark mixing Indirect evidence for new physics

W/Z QCD Tests Precision measurement of EW parameters

Top Precision measurement of EW parameters Most massive particle new physics

Higgs The heart of EW symmetry breaking

Searches Directly look for new particles/effects predicted by specific beyond the SM models


B MixingB Mixing

Weak Mass Eigenstates Neutral B’s can mix

Time Evolution

The B is a Notorious Flip-Flopper !

matrices 2x2 Hermitian

2

,M

)t(B

)t(BiM

)t(B

)t(B

dtd

i

]1[

]1[

00

00

)tmcos(e)t)(BB(P

)tmcos(e)t)(BB(P

qt

qq

qt

qq

q

q

sd,

t

t

s,d

b

b

WW0

sd,B 0sd,B

*tbV

tbVstd,V

*std,V


Mixing Now !Mixing Now !

md = 0.502 ± 0.007 ps-1

30 separate measurements !

ms > 14.5 ps-1 (95% CL)

Heavy Flavour Averaging GroupWinter 2004 update


The Importance of B’ing StrangeThe Importance of B’ing Strange

Bd Mixing |Vtd| (side of triang.)

So Why should we bother with Bs ?

s

d

Bd

Bs

BdBd

BsBs

ts

td

mm

mm

BF

BF

V

V

Ratio reduces error: 14% 5%


Some Hints ?Some Hints ?

SM Preferred Region:

16.5 – 25.3 ps-1 (“1 ”)

SM Preferred Region:

16.5 – 25.3 ps-1 (“1 ”)

HFAG: summer 2004

CKMFitter: ICHEP 2004


Anatomy of a Bs Mixing AnalysisAnatomy of a Bs Mixing Analysis

1. Identify Bs Candidates produce them get them to tape reconstruct them

2. Determine Proper Time decay length ct = L /

3. Mixed or Unmixed flavor at production flavor at decay

4. Fit for ms

or ampl at ms

Sensitivity

N = no. of Bs candidates = frac. of Bs in N D = 1 – 2xProb(mistag) S/B = signal/ bgrd in N t = ave. proper time res.

22

2

2Signif /)m( tse

BSSDN

-B

K

0D0sB

-sD

K

K


Finding the Elusive BsFinding the Elusive Bs

1. Produce a Bs

fs ~ 0.1 vs. fd = fu ~ 0.4

2. Trigger on the Event L1 is the bottleneck Di- (Pt>3, ||<2.2) no presc. Di- (Pt>1.5, ||<2.2) prescale 1- (Pt>3-5, ||<2.2) prescale

3. Reconstruct Bs

Ds(*) l v BR ~ 10%

more stat’s

poorer t

(can trigger on lepton) Ds

(*) n BR ~ 0.5% less stat’s

better t

Ds , K*0K KK, K*K

-B

K

0D0sB

-sD

K

K

Experimental Challenges 20–40% of Bs out of accept

when trigger on opp. lepton Low Pt trigger lepton Low Pt tracks

-B

K

0D0sB

-sD

K

K


We Reconstruct B’s !We Reconstruct B’s !

Bd J/ Ks0

B± J/ K±

B D* X

’ J/ + -

X(3872) J/ + -


Unique to the Tevatron !Unique to the Tevatron !

Bs J/ Lifetime s

Bc J/ X Signal: 135 ± 18 (>5) M: 6.11 ± 0.17 ± 0.44 GeV

210 pb-1

b J/

250 pb-1


Mixing SamplesMixing SamplesB

d M

ixin

gB

s M

ixin

g

B X

Bs Ds X~40 / pb-1

250 pb-1

B D0 X

200 pb-1

B D* X~100 pb-1

200 pb-1

200 pb-1

Bs Ds X~25 / pb-1

B K*K X


How Long Does It Live ?How Long Does It Live ?

1. Estimate Decay Length (Lxy) Beam Spot

size ~35 m in x-y average vs. evt-by-evt

Bs Decay Point vertexing

Decay Length Error (L)

2. Estimate B Momentum ct = L / Bs Ds

(*)

very precise Bs Ds

(*) l v

missing v must use MC to est. corr.

-B

K

0D0sB

-sDK

K

3. Proper Time & Error

Experimental Challenge understand resolution

KPM

Lct meast

Bxy

22

0

2

Kt

LK

BB

L

B

t


Study Resolution w/ LifetimesStudy Resolution w/ Lifetimes

(t))N(B

)N(B0

Bs J/

s J/ Bc J/ X

220 pb-1

210 pb-1

250 pb-1


...the Results...the Results

Mode DØ Measurement [ps] HFAG Ave. [ps] ct Res. [m]

B0 / B+ (D(*) ) 1.093 ± 0.021 ± 0.022 1.086 ± 0.017 35

B+ J/ K+ 1.65 ± 0.08 +0.08/-0.12 1.671 ± 0.018 29

Bd J/ K*0 1.473 ± 0.051 ± 0.023 25

Bd J/ K0s 1.56 +0.32/-0.25 ± 0.13 1.536 ± 0.014

Bs J/ 1.444 +0.098/-0.090 ± 0.020 1.461 ± 0.057 25

b J/ 1.22 +0.22/-0.18 ± 0.04 1.229 ± 0.080

Bc J/ X 0.45 +0.12/-0.10 ± 0.12 0.46 ± 0.17


To Mix or Not To MixTo Mix or Not To Mix

1. Tag Flavor at Production using Opposite Side Soft Lepton (muon) Tag

-charge b-charge Jet Charge Tag

2. Tag Flavor at Production using Same Sidea. Charge of leading non-Bs

hadron B** B h or fragmentation

3. Tag Flavor at Decay D-charge b-charge

Experimental Challenge Measure mis-tag rate in Data Control Samples: B± decays

B+ D0 +, B+ J/ K+

-B

K

0D0sB

-sD

K

K

h

i,t

ii,t

P

qP Q Jet

Method (%) D (%) D2 (%)

Soft Muon 5 45 1.0 ± 0.2

Jet-Q / Same Side 68 15 1.5 ± 0.3

BaBar/Belle ~20


Putting it All TogetherPutting it All Together

50K Simulated Bs Ds v Events: ms = 15 ps-1

cs

reduces ampl of osc big effect at large t

big effect at small t


Testing the Waters with Bd MixingTesting the Waters with Bd MixingD

Ø P

reli

min

ary:

200

pb

-1

ctvis (m)

Un

mix

-Mix

Asy

m(t

)

“B+” D0 + X(JetQ+SST)

“B0” D*- + X(JetQ+SST)

“B0” D*- + X(SLT)

cd


Nostradamus PredictsNostradamus Predicts

Mode Yield / pb-1 D2 (%) S/B t (fs)

Ds() X 40 2.5 0.66 120

Ds(K*K) X 25 2.5 0.27 120

Ds(*) 1.4 2.5 1 70

• Add Ds & e modes

• Combine Results

Sensitivity to SM Fit Region

Sensitivity for1 fb-1

Signif2

1~ m)(

Competitive Limits

Spring 2005

Competitive Limits

Spring 2005


DØ’s Road AheadDØ’s Road Ahead Establish Bs Mixing Measurement

systematic studies: tagging, resolution produce ms limit with current data

And Make Improvements include electron modes better resolution & momentum estimates

But the Measurement is within Our Grasp !

And That’s Not All ! sin(2) from J/ Ks

0 & J/ Rare Modes: Bs + - & Bd + - K*

Studies of the Bc & b

Precise measurements of production


DØ,CDF BaBar,Belle LHCb Atlas,CMS BTeV

Beams e+e- pp pp

ECM [TeV] 1.96 0.0106 14 14 1.96

Timeframe now 2009 now 2006 2007 2007 2009

Inst Lumi(1032 cm-2s-1)

0.4 2.8 100 2.0 100 2.0

Data Set [fb-1] 0.3 9 150 500 1012 bb/yr 100/yr 1011 bb/yr

Further Down the PathFurther Down the Path

pp pp


The Next StepsThe Next Steps

Quantity Mode Curr. W.A. Next Step Improvement

|Vcb| BXclv (41.4 ± 2.1)10-3 theory

|Vub| BXulv (4.66 ± 0.43)10-3 theory

ms BsDslvX,Ds > 14.5 ps-1 DØ,CDF ~20-25 (5 w/ 2 fb-1)

BTeV,LHCb ~50 (1 year)

sin 2 0.726 ± 0.037 BaBar,Belle ± 0.03 (0.5 ab-1)

CDF,DØ ? ± 0.03 (2 fb-1)

0.39 ± 0.10 BaBar,Belle ± 0.03 (1.5 ab-1)

BD0CPK,K (77 ± 25)o BaBar,Belle ±14o (1.0 ab-1)

B,, (100 ± 10)o BTeV,LHCb ±4o (1000 tag )

Rare BR(Bs+-) < 5 10-6 Atlas,CMS (3.5±0.8)10-9 (100fb-1)

Rare K’s BR(K+vv) NA48/3 ~50 evts (2 years)

BR(K0vv) < 5.910-7 KOPIO/E391 O(100) evts – 2009

sccb

sqqb

103010.89- 101.47 .


ConclusionsConclusions

B-Hadrons provide a Sensitive Probe of EW Symmetry Breaking & Physics Beyond the SM allow classes of models to be favored/ruled out complementary to direct searches for new particles

The DØ Experiment is Poised to make Major Contributions in the next few years QCD: lifetimes, spectroscopy, production… CKM: Bs Mixing, s, sin 2, sin 2s…

Rare: Bs+-, B K*+-

Future Experiments will keep b’s at the Vertex for many years to come !


Backup SlidesBackup Slides


Theoretically Clean FCNC B0 decays forbidden

at tree level in SM

Can be large beyond SM 2HDM tan4 MSSM tan4

Plays to DØ’s Strengths Muon Triggers to large Low Backgrounds

Rare Decays and FCNCsRare Decays and FCNCs

Mode BR(Bd) BR(Bs)

+- 1x10-10 4x10-9

+-K* () 1.5x10-6 1x10-6

+-Xs 6x10-6

K* 4.4x10-5

+ - Mass [GeV]

BR(Bs + -) < 5.010-7 (95% CL)BR(Bs + -) < 5.010-7 (95% CL)

240 pb-1


Tevatron Run II

LEP CLEO B-Fact LHC

Collisions e+e- e+e- e+e- pp

Ecm [GeV] 1960 91 10.5 10.5 14000

Species Prod all all Bd,B+ Bd,B+ all

[b] ~100 0.007 0.001 0.001 ~500

S/B [%] 0.1 0.15 ~0.3 ~0.3 0.6

In Accept. [%] ~6 ~100 ~100 ~100 ~5

Luminosity [cm-2s-1] 11032 ~1031 7.51032 11034 11033

Rate w/o trig [Hz] 600 0.07 0.8 10 25,000

<Decay L> [mm] 0.45 3 0.025 0.26 1.7 (Lxy)

b Facilitiesb Facilities

pp

)b(b


Measuring Measuring

d

b

0dB

W

*cbV

csVs

c

c

d0K

J/

b

d

W

t

t b

0dB 0

dB s

c

c

d0K

J/

tbV *tdV

tdV *tbV *

cbV

csV

s

c

cW

b

d

0dB

s

d0K

cc J/

cbV

*csV 0K

*cdV

*cdV

csV

*csV

s)cc(b KJ/B 0s

b

dW

tt b

0dB 0

dB 0K

tbV *tdV

tdV *tbV

*cbV

csV

c

d

q

q

s

',

b

d

0dB

c cc

csV *cdV

s0K

s

q

q',

0Kd

cdV *csV

cbV

*csV

b

0dB 0K*

cbV csV

c

d

q

q

s

',

d

s)qq(b KB 0s ',

fCP

fCPfCP A

A

p

q

B-Mixing Decay

i

cd*

cs

*cdcs

cs*

cb

*cscb

td*

tb

*tdtb e

VV

VV

VV

VV

VV

VV)K( 20

i

cd*

cs

*cdcs

cs*

cb

*cscb

td*

tb

*tdtb e

VV

VV

VV

VV

VV

VV)K( 20


Beauty as a ProbeBeauty as a Probe

B-Physics is a Good Place to Probe EW Sym. Breaking measurable unitarity triangle QCD corrections to predictions small

1. Look for Modifications to Couplings Rare Decays Different EW Sym. Breaking Struct. Different Couplings Most Interesting Channels = Rare or Zero in SM

2. Check for NP in Consistency of CKM Picture CPV & Mixing Need meas’s of each parameter in several modes Use SM loop level processes (NP effects can compete here) Differences in param’s measured by proc’s w/ diff. flavor struct.

But Wait, There’s More – QCD ! b-production, spectroscopy, lifetimes…


The J/The J/


ResonancesResonances

= 7 MeV

= 3 MeV

h.evans columbia colloquium: 18-oct-04 1 the b-quark a vertex of new physics hal evanscolumbia u

Documents

evans columbia colloquium

ew symmetry breaking

higgs mass

lepton mixing matrix

columbia university

grand flavor plan slide

b s mixing

solid ground lep ewwg