Heavy Flavour Physics at the Tevatron

Farrukh Azfar, Oxford University (CDF)

Zero to Z0 Conference: Fermilab, May 12-14 2004

Overview of this presentation:

Preliminary:

1) Tevatron performance, Beauty physics at hadron colliders

2) CDF and D0 detectors, relevance for B-physics Physics Results & Prospects:

3) Tests of Heavy Quark Expansion (HQE) Masses and Lifetimes of B hadrons. Hadronic Moments.

4) Search for Flavour Changing Neutral Current (FCNC), Rare decays…

5) Mixing and CP violation (CPV), Toward Bs-mixing & CKM angle

6) Conclusion and Summary

Tevatron pp collider upgrade & performance, integrated luminosity

Performance Improvement:

-Collision rate: 3.5 s 396 ns

- Bunches: 6x6 36x36

-Center of Mass energy: 1.81.96 TeV/c2

-Peak luminosity : 2.4x10317.2 x1031cm2s-1

(Below target by x2.5, but improving)

Run-IIa -Goals are Ldt=2fb-1 (x20 Run-I, 1992-96)

Run-II Tevatron Upgrades: -Main Injector for Tevatron -Higher proton intensity -Anti-proton transfer efficiency increased -Anti-proton recycler (coming after autumn)

CDF

Data taking efficiency~80-90% for CDF & D0 Results in this talk:CDF analyses ~65-250 pb-1 D analyses ~115-250 pb-1

290 pb-1 on tape at CDF & D0

Why Beauty at the Hadron-Hadron Colliders ?(bb) at (4S) = 1nb (B-factories) (Compare bb

production (bb) at Z0 = 7nb (LEP) cross section)(bb) at pp (1.96TeV/c2)=150b (Tevatron Experiments)

More B @ Tevatron but inelastic is 103 x (bb) -Select b-data online, key: right detector & triggers -Rewards: all B-hadrons e.g. B, B0, Bs, Bc

, b … (unlike B-factories) & higher than at Z0

Clever Online B Selection (Triggers):

”Traditional” Use leptons from e.g. BsDs+- CDF & D0

(single-lepton) & B J/K*, J/+:CDF & D0 (di-lepton) ”Modern” long B lifetimes large impact parameter (IP) of daughter tracks : CDF (D0 in progress)SVT trigger: purely hadronic decays of B and Charme.g. D0+- , BsDs

+-, Ds+ K+K- (1st @ hadron machine!)

CDF Apply High IP requirement in single-Lepton data as well

The CDF & D0 Detectors in Run-IICDF Detector

D0 Detector

CDF & D0 Detectors are bothMulti-purpose with:-Axial Solenoid-Inner Silicon micovertex detectors-Outer trackers -Calorimetry -Muon ID-Muon Triggering (CDF & D0)-High IP Track triggering (CDF)

D0: Better calorimetry, better muon & tracking coverageCDF: Better momentum measurement, also can select high IP tracks, some Hadron ID with dE/dX, TOF

Physics Results, Testing HQE: B-hadron lifetimes, massesGoals, Techniques

Fully Reconstructed B from J/di-muon trigger (e.g. Bs J/) or High IP trigger (e.g. BsK+K-)-Find vertex, 2-d distance: Lxy invariant mass: MB momentum in 2-d: Pt

B Find proper time: c= Lxy. MB/PtB

- Fit mass distribution only or mass and lifetime distributions

-Decays selected usingSVT trigger have biased c-”Turn-on” near low IP cut-”Turn-off” at high IP cut-Bias fix underway: Then measure Lifetimes in BsDs

+-

etc….

Partially Reconstructed e.g. Bs +Ds-, B+ D0

1-lepton (+High IP track CDF )trigger: -Missing means: c= Lxy.MB/Pt

B =Lxy(D0+).MBK./Pt

(+D0)

-K= Pt(+D0) /Pt

B from MC: high statistics but worse c

Goal: test the HQE Predicted B Lifetime hierarchy : Bc << b0 ~ b < Bd ~ Bs < B- < b-

Physics Results, HQE: Bs J/, Lifetime and Mass:J/ +- , K+K- (using di-muon (J/) trigger): Run-I: ~60 at CDF. Run-II: D0~403, CDF~269 Largest sample of fully reconstructed Bs remains at the Tevatron

CDF:M(Bs)=5366.010.73(stat)0.0.33 (sys)MeV/c2 D0:M(Bs)=53605 MeV/c2

CDF: (Bs)=1.3470.0990.013 ps & Bs)/Bd)= 0.89 0.072 D0: (Bs) = 1.1900.180.014 ps (69 events, update in progress)

Mass & Lifetime Results from assorted other fully reconstructed decays:CDF: B)= 1.25±0.26±0.10 ps (bJ/), M(B)=5619.7±1.2±1.2 MeV/c2 Bs and B mass measurements remain worlds best..

Physics Results (aside): Bs width difference s

angular separation of CP eigenstatesCDF & D0 fit 1 lifetime But: there are 2: CP+,CP- & Bs=1/CP+-1/CP-

s: predicted to be large ~10%, provides SM consistency check: s=A.MBs If MBs is large & s is small or vice-versasign of new physics

Need to measure lifetime(s) : can do, and determine CP content: Use angular analysis…(CDF) and put them together (when we have higher statistics)Convenient basis: transversity Allows easy separation of CP content of BVV decays Analyse: Bs J/&Bd J/K* as a check(J/+-, K+K-, K*(892)K+-)

PDF has 3 angles: f() with amplitude parameters A,A A0

so that: A2=CP odd fraction & A2+A02

=CP even fraction

Physics Results (aside): Bs width difference s

angular separation of CP eigenstates

Polarization analysis indicates CP+ = 0.77±0.10: The larger the dominanceof a CP eigenstate the greater the accuracy of s Analysis will be done at D0 as well !

Using 176 BsJ/ & 993 BdJ/K*(892) (as a check)

Compatible with BaBar & Belle

Physics Results Testing HQE: Charged to Neutral B-Meson lifetime ratio (D0)

D0: Charged to Neutral B-Meson Lifetime Ratio: +/0 Use:-B D*(2010)-X: mostly Bd

-B D0X : mostly Bu±

-Calculate ratio of events/lifetime bin N+/N0 ~e-(+/0-1)t (K-factor)t

-Calculate expected ratio using all BRs in terms of k= +/0, and N(overall normalization)Minimize 2 determine k and D0 Result: +/0 = 1.093 ± 0.021 ± 0.022, =1.001±0.012

BaBar: B+)/Bd)= 1.064 ±0.031 ±0.026 CDF: B+)/Bd)= 1.080

0.042 Belle: B+)/Bd)= 1.091±0.023±0.014 (B+J/K+ & BdJ/K*0)

One of theWorld’s best singlemeasurements

Physics Results Testing HQE: More B decays used:bJ/ (CDF)

B+J/K+(D0)

BdJ/K* (D0)

B+J/K+

(CDF)

Physics Results: Hadronic Moments from D** decays1) HQE:(BXcll)~GF

2|Vcb|2 mb5.(Cn/mb)n with Cn = <0|On

HQE|0> (non-perturbative, can extract from data)

2) Free parameters at O(1/mb), 1+2 @ O(1/mb2) , etc….

3) Moments M1,M2 of Xc invariant mass distribution:

from B-decays :

have expansions similar to 1) i.e..in terms of 1+2 (sH=MXc2)

4) By finding pdf & hence M1, M2 ->constrain , 1 , & improve Vcb measurements

5) Now First 2 pieces from D*, D0 are well known. f** (sH) comes from narrow &wide D**+higher order(resonant & non-resonant):

max

min

max

min

2 21

2 2 2 22 1

1( )

1( ) ( )

H

H

H

H

ssl

H H HD Dssl H

ssl

H H H H Dssl H

dM ds s m s m

ds

dM ds s s s m M

ds

|Vcb|incl= (41.9 ± 0.7exp ± 0.6theo) 10-3

contains , 1

1 sl

sl H

d

ds

1 sl

sl H

d

ds

Physics Results : Hadronic MomentsReconstruct B- D**0 l- Find and D**0 consistent with B parent (vertex). Use lepton + high IP track data.

Reconstruct D**0D*+- & D**0D+ -

decays are reconstructed, moments: m1,

m2 calculated wrt f**(sH)

f**(sH) distribution

M1 M2 from D, D* & D**best single measurement !

In going from m to M assume:-lepton p in B rest frame >700 MeV-MD, MD* , Branching ratios from PDG-Only D** decays to 1 + D, D*

Rare B decays: B s(d)+- at CDF

-Use high-mass di-muon data-BRSM(Bs+- )=(3.8 ± 1.0) 10-9 some extensions predict x103 BRSM

- Variables: Mass, lifetime, from vertex & Isolation- 1 background event expected, 1 event seen: no excess->BR limit

“Blind” analysis: cuts optimization before looking at the signal mass region

BR Upper Limit at 95% CL 7.5x10-7 Bs (World’s best)1.9x10-7 Bd

BR Upper Limit at 90% CL 5.8x10-7 (Bs )1.5x10-7 (Bd )

Bd result: Belle: 1.6x10-7 & BaBar 2.0x10-7

Submitted to PRL

-Use MC for signal data, background for cut optimisation:-Expect 7.3 1.8 background events in signal region

Expected limit (Feldman/Cousins):

Br(Bs + -) < 9.1 10-7 @ 95 % CL (stat only)Br(Bs + -) < 1.0 10-6 @ 95 % CL (stat + syst)(expected signal has been normalised to B J/ K forBR limit calculation)

180 pb-1

The analysis has not been unblinded yet (signal region still hidden).

It is still being optimized (without bias) and expected to improve …

Physics Results Bs limits from D0:

Rare Decays: Bs :Observation & BR (SVT Trigger) CDF1) Bs decays via second order weak decay

2) SUSY coupling could enhance the SM BR (10-5)3) Comparison of angular distributions of various

B VV decays can determine and

BR= (1.4 ± 0.6 ± 0.2 ± 0.5 (BR))x10-5 (SM 3.7x10-5)

Upper Limit : <2.7x10-5 @ 95% CL

First “observation” (4.8) ! Blind analysis

1) Normalization Mode: BsJ/ 2) Relative Efficiencies from MC 3) N(Bs J/) is corrected for: Reflections from Bd J/K*4) J/ K+K- BsJ/BRstaken from PDG

s ss corr

s

N(B ) (B ). ( / )ε(ψφ)BR(B φφ)

N(B ) ε(φφ) ( )

φφ BR ψφ BR J

ψφ BR K K

Mixing and CP violation (CPV) in Bd,s decays, basics:

Same side taggingOpposite side tagging

Concept: Look for ± (K±) from hadronization of B (Bs)of interest, Higher

Concept:Look forB on opposite sideof B of interest -Look for ,e -Use weighted jet-charge Disadvantages: Opposite B not in acceptance (60%) or mixes (B0)

Issues: Tagging Flavour Correctly… ....& being able to tag at all

tagnowrongcorrect

wrongcorrect EfficiencyNNN

NN

wrongcorrect

wrongcorrectDilution NN

NND

Statistical power: N tagged events = D2N pure events

Check algorithms in known b-flavour decays eg B± J/K± Prepare for Bs mixing by first doing Bd mixing

-Mixing: tag B-flavour at birth, decay to flavour specific state: asymmetry: Amix~Cos(md,st)-CPV: tag B at birth, decay to CP eigenstate: asymmetry(t) Acpv~Acpv,direct.Cos(md,st)+Acpv,mixing.Sin(md,st)

Proof of principle: Bd mixing at D0 -Data sample: lepton triggers -Bd D*(2010)-X (D*-D0-,D0 K+-)-Find +, D0,- consistent with B-Select events within |M(D*-,D0)PDG- M(D*-,D0)|<0.04GeV/c2

-Opposite-side tags flavour -Use PDG BRs to calculate expected & observed asymmetry(t)-Md & Purity are free parameters & fit

250 pb-1

Preliminary results: md = 0.506 0.055 0.049 ps-1

Consistent with world average: 0.502 0.007 ps-1

Tagging efficiency: 4.8 0.2 % Tagging Purity: 73.0 2.1 % First D0 mixing Measurement !!

Proof of principle CDF (Run-II) Md measurement

First Run-II mixing result: same side tagging (SST)Find fragmentation from B, track near B with lowest relative PT B+J/ K+, D0+ to check tag, B0J/ K*0, D for md

CDF Run-I md (all methods) = 0.495 ± 0.026 ± 0.025 ps-1

-1.1KB0J/K*0

(J/data)-4.9K B0D (SVT Trigger!)Md=0.55±0.10 ps-1

Dilution (D) =12.4 %D2=1.0±0.5

Work on jet-charge & opposite side muonTagging continues

Physics Prospects: Toward Bs mixing at CDF : fully reconstructed decays : B0

s Ds

First observation of mode BsDs+-with (Ds+

, K+K-) ! “Flagship” Mode for Bs mixing !

Decays we plan to use:

B0s Ds

,

B0s Ds

Proper time resolution:

t = 67 fs t PT/PT

-Currently have reconstructed only Ds

-Reconstruct with more Ds decays eg: K*0K, +

to improve yields…

-Need to tag initial B flavour-projection awaits final D2

Physics Prospects: Toward Bs mixing semi-leptonic decays:

-Also Lifetime measurement provides valuable constraint on Bs:

=(cp+2+cp-

2 )/(cp++cp-) as in B0s Ds

Use leptons (CDF: lepton+high IP track) & select Bs+Ds-

X Find lepton+Ds-- K+K- lepton has charge opp.

to Ds

Plots have different mass resolution and S/B

Physics Prospects: CP violation in Bh+h- (SVT data) decays determining angle CDF), Method:

u-

bW

u

ud-

b dW

u,c,t

b su,c,t bW

us

W

Tree > penguin in B vice-versa in BsK+K-

MC

Lumi~180pb-

1

Bh+h- from hadronic triggerData ! (891 events)

1st Stage Statistically Separate Bd Bd K+Bs K+BsK+K-- Use: M vs =(1-p1/p2)q1:6 distinct shapes for +-

K+K-, (Bd,Bs) K+ K-

-Use: dE/dX distinguishes Ktoin the future use mBd mBs too…

dE/dx check: Use D*±D0, D0 K

Four unknowns In Asymmetry(t):d=ratio of penguin/tree hadronic matrix elementsphase of d = weak phases Constrain from B-factories, measure by fitting asymmetry (t)Proposed by: R.Fleischer, PLB459 1999 306

Physics Prospects: CP violation in Bh+h- decays determining angle CDF)

Results use 65 pb-1 sample, 1.16 dE/dX K separation:Update with dE/dX (1.4) & 180 pb-1

underway !

Yields (Results from 65 pb-1)BdBdKBsKBsK+K- BsK+K- First Observation !)Sanity check (spot on !): Measure Ratio of Branching Ratios

CDF : (Bd-)/(Bd K+-) = 0.26 ±0.11±0.055, PDG:

0.13 0.010.290.12 0.02

Finally we expect:

(Fleischer method) (2fb-1): () =±10(stat) ±3(syst SU(3) breaking)

Ratios of BRs (CDF) & ACP(Bd) (B-factories): Check SM consistency (D.London)

hep-ph/0404009

U-Spin relationship

SM check by comparison with ACP in Bd

58°<<72°

BR

(Bs

K+K

-

) BR

(Bd+-

)

ACP(Bd+-)dir

0.13 0.010.290.12 0.02

Conclusions:

1) CDF & D0 are completing 1st phase (~250pb-1) of data taking : a) Current (Bu

+)/Bd0) ) surpasses theoretical accuracy. Also

tests of vertexing & tracking (for future MBs and CPV) b) Search for FCNC set limits on rare BRs c) Prepare for Bs mixing: Establish by measuring Bd mixing

first !

2) Next phase (>250pb-1 &<500pb-1) will: a) set limits on (or observe) Bs mixing b) set limits on Bs

c) search for CPV in the neutral B system d) Continue to improve limits of Rare Decay BRs

3) Final Phase (end Run-IIa) (>500pb-1 and <2fb-1) all of the previous &:

a) Achieve better than 1% accuracy on (Bs)/Bd) ) & (Bd)/b))

b) Measure Bs mixing parameter xs expect to measure (s)~5%

c) Measure CKM angle d) ……and search for unexpectedly large CPV in Bs J/ Last phase will be mostly complementary to the B-factories

Backup Slides

Aside: Physics Results: Ratio of branching ratiosof BsDs

to BdD

Interest in BsDs is mostly due to Bs mixing but:we’ve also

measured the ratio of branching ratios (BsDs)/(BdD)

Normalization mode is BdD, D K

Kinematically ~BsDs, Ds

, K+K-

( ) ( ) ( ) ( )

( ) ( ) ( )s s s s s s

d d d d

N B f Br B D Br D Br K K

N B f Br B D Br D K

Ratio of Bs to Bd signals is:

Where are determined from Monte-Carlo

D, Ds BR are from PDG, obtain:

( )0.44 0.11( ) 0.11( ) 0.07( )

( )s s s

d d

f BR B Dstat BR syst

f BR B D

Using fs/fd =0.273±0.034 from PDG obtain:

( )1.61 0.40( ) 0.40( ) 0.26( ) 0.20

( )s s s

d d

BR B D fstat BR syst PDG

BR B D f

…we’re beginning to fill in PDG section on the Bs

Data Samples: B and Charm from the hadronic trigger

Prompt CharmD0K 86.5 0.4 % (stat)

D*D0 87.6 1.1 % (stat)

DK 89.1 0.4 % (stat)

Ds 72.4 3.4 % (stat)

0.5M Charm decays at CDF 10-20% come from B: Great Potential for B and Charm Physics, opens at least as many avenues as J/ trigger

Some charm is prompt

..to separate prompt Ds from Ds coming from B

An example of B reconstructed Using data from this trigger:

D from direct charm:Points back to beam spot

D from B has a impactParameter wrt beam spot

We have B and tons of Charm as well !

..Some charm is from B

Physics Results: Average B-hadron lifetime from partially reconstructed BJ/X decays

Results from D0 and CDF

B=1.5610.0240.074 ps D0 (40 pb-1)

B=1.5260.0340.035 ps CDF (18

pb-1)

Both consistent with: PDG: B = 1.564 0.014

D0 Inclusive B Lifetime

This is a “sanity check” of our BJ/sample: Obtain Average B hadron From all BJ/(+other stuff) decays: B is not fully reconstructed

Partially reconstructed B-Correct for missed daughters: F(PT) (from by Monte-Carlo)-B is an estimate -it is the average lifetime of all hadrons decaying to J/

( )xy

T T

Mct L

P F P

T

BT

BT P

P

M

MPF )(

Signal lifetime is modelled by :

Complete likelihood function:

( / )

( , , ) ( , )

( , , ) . ( , , ) (1 ). ( )

Bt

signal B t tB

B t signal B t background

eF t g t

F t f F t f F t

Complete event probability density

Background shape from side-bands

Bs width difference s and angular variable separation

Two CP states: lifetime

Two CP states: transversity

Total function and normalization

21

22

( ,1) 0.375(1 cos )

( , 2) 0.75(sin )

F

F

1 1 1 2( , , ) [ . ( , , ). ( ,1) (1 ). ( , , ). ( , 2)]. ( , , )signal CP t B CP t B m BF m t f F t F f F t F F m M

( , , ) . ( , , ) (1 ). ( , , )total s signal s backroundF m t f F m t f F m t ( , , ) 1totalF m t dmdtd

1

2

( / )

1 11

( / )

2 22

( , , ) ( , )

( , , ) ( , )

B

B

t

t B tB

t

t B tB

eF t g t

eF t g t

Current limit (LEP): s / s <0.31, from branching ratio of BsDs±(*)Ds(*)

Note: SM CP violation in this mode: O(3%), if large new physicsCP asymmetry = sin2 s, measured= s,SM.Cos2complementary)

One lifetime(width) has been fit in this mode

1) But contains two distinct lifetimes: CP+ & CP- Bs, significant lifetime (width) difference:

s=1/B1-1/B2

2) Extract s : fit two lifetimes, use single angle to separate CP+ and CP- Bs: (Transversity angle

3) SM prediction for s ~0.10s also s = A.xs (xs = Bs mixing parameter) if s is small and xs is large or vice-versa Sign of new physics

3) CDF prediction for 2fb-1 (s)~0.05

Physics Results: lifetime, mass, from fully reconstructed B J/ X modes: Standard Technique :

Data from J/ di-muon trigger: 1) Reconstruct vertex according to decay topology2) Calculate decay proper time mass & errors3) If fitting for mass:fit mass only4) If fitting for lifetime:Fit mass and lifetime using bi-variate Probability density function (PDF) in likelihood

2

2

( / )

( )( )

( , , ) ( , )

( , , )2

( ) ( , , )

( , ) ( , , ). ( , , )

( , ) . (1 ). ( , )

( , ) 1

B

B

m

t

t B tB

m M

m B

m

signal m B

signal t B m B

total s signal s backround

total

eF t g t

eF m M

F m F m M

F m t F t F m M

F m t f F f F t m

F m t dmdt

1) Signal Lifetime :

2) Signal Mass :

4) Signal pdf in mass and lifetime:

6) Normalization : mass & lifetime

3) Signal for Mass only analyses:

5) Signal for lifetime analysis:

An Example B+ ->J/ K+ at CDF

Both the mass and lifetime distributions are fit in a single step. Technique is applied to :

B+ J/ K+, B0 J/ K0* (K0* K),

Bs J/ ( KK), bJ/ (p)

Probability Density Function (pdf)

B physics prospects(with 2fb-1)

Bs mixing: Bs →Dsπ(Ds3π) (xs up to 60, with xd meas. one side of U.T.)

Angle : B0→ J/ψ Ks (refine Run1 meas. up to (sen2) 0.05)

CP violation, angle γ : B0→ ππ(πK), Bs → KK(Kπ)

Angle s and s/ s : Bs→ J/ψ (probe for New Physics)

Precise Lifetimes, Masses, BR for all B-hadrons: Bs, Bc, Λb … (CDF observed: Bc → J/ψ e(). Now hadronic channels Bc → Bs X can be explored)

HF cross sections (beauty and charm)

Stringent tests of SM … or evidence for new physics !!

Both competitive and complementary to B -factories

Physics Results: Average B-hadron lifetime from partially reconstructed BJ/X decays.

Results from D0 and CDF

B=1.5610.0240.074 ps D0 (40 pb-1)

B=1.5260.0340.035 ps CDF (18

pb-1)

Both consistent with: PDG: B = 1.564 0.014

D0 Inclusive B Lifetime

This is a “sanity check” of our BJ/sample: Obtain Average B hadron From all BJ/y (+other stuff) decays: B is not fully reconstructedIf Fully reconstructed B-ct = c.(time in B rest frame)-Lxy = 2-d decay length-MB = mass -PT = transverse momentumIf Partially reconstructed B-Correct for missed daughters: F(PT) (from by Monte-Carlo)-B is an estimate -it is the average lifetime of all hadrons decaying to J/

( )xy

T T

Mct L

P F P

T

BT

BT P

P

M

MPF )(

B

xy BT

Mct L

P

Signal lifetime is modelled by :

Complete likelihood function:

( / )

( , , ) ( , )

( , , ) . ( , , ) (1 ). ( )

Bt

signal B t tB

B t signal B t background

eF t g t

F t f F t f F t

Complete event probability density

Background shape from side-bands

Sin(2) in B0J/Ks

N(B0)(t) - N(B0)(t)

N(B0)(t) + N(B0)(t)=Dsin(2)sinmd

tACP(t) =

N(J/ Ks) from scaling Run I data:• x 20 luminosity

8,000• x 1.25 tracks at L1 trigger 10,000• x 2 muon acceptance 20,000• Trigger on J/ e+e + 10,000

In Run1 measured:

sin(2)=0.79±0.39±0.16

B0 J/ Ks ; J/

(400 events)(+60 B0 (2S) Ks)

sin(2)=0.91±0.32±0.18

Combined D2: from 6.3% to 9.1% (Kaon b-tag)

Same S/B = 1

Expect: s(sin2b) 0.05

With 2fb-1 can refine this measurementAlthough: no way to compete with B-Factories !

)) (2 sin( S B

ND1

2

1Stat. Error:

Systematic ~ 0.5xStatistical

(scales with control sample statistics)

ms/md

Tevatron Performance

July ‘01

Now

Tevatron operations • Startup slow, but progress steady !

• Now: L ~3.5 x 1031 cm-2s-1

integrating ~ 6. pb-1/week• … still factor 2-3 below planned valuesadditional improvements (~10-20%) expected from Jan. 3weeks shutdownCDF operations

• Commissioning: Summer 2001• Physics data since February 2002• Running with >90% Silicon integrated

since July 2002

Initial Luminosity3.8 x 1031

110 pb -1

July ‘02

On-tape Luminosity

Luminosity (on-tape): ~20pb-1 until June (analyses in this talk) Additional 90pb-1 July – December Reach 300- 400 pb-1 by October 2003

Feb ‘02

Quadrant of CDF II Tracker

LAYER 00: 1 layer of radiation-hard silicon at very small radius (1.5 cm) (achievable: 45 fs proper time resolution in Bs Ds )

COT: large radius (1.4 m) Drift C.

• 96 layers, 100ns drift time • Precise PT above 400 MeV/c

• Precise 3D tracking in ||<1

(1/PT) ~ 0.1%GeV –1; (hit)~150m

• dE/dx info provides 1 sigma K/ separation above 2 GeV

SVX-II + ISL: 6 (7) layers of double-side silicon (3cm < R < 30cm)• Standalone 3D tracking up to ||= 2• Very good I.P. resolution: ~30m (~20 m with Layer00)

TOF: 100ps resolution, 2 sigma K/ separation for tracks below 1.6 GeV/c (significant improvement of Bs flavor tag effectiveness)

TIME OF FLIGHT

CDF II Trigger System3 levels : 5 MHz (pp rate) 50 Hz (disk/tape storage rate) almost no dead time (< 10%)

XFT: “EXtremely Fast Tracker” 2D COT track reconstruction at Level 1

• PT res. pT/p2T = 2% (GeV-1)

• azimuthal angle res. = 8 mrad

SVT: “Silicon Vertex Tracker” precise 2D Silicon+XFT tracking at Level 2

• impact parameter res. d = 35 m

Offline accuracy !!

CAL COT MUON SVX CES

XFT XCES

XTRP

SVTL2

CAL

L1CAL

GLOBALL1

L1MUON

L1TRACK

GLOBALLEVEL 2 TSI/CLK

CDF II can trigger on secondary vertices !! Select large B,D samples !!

Matched to L1 ele. and muonsenhanced J/ samples

SVT: Triggering on impact parameters

d

beam spot

COT track ( 2 parameters) 5 SVX coordinates

Impact Parameter (transverse projection)

• Combines COT tracks (from XFT) with Silicon Hits (via patternmatching) • Fits track parameters in the transverse plane (d, , PT) with offline res.• All this in ~15s !• Allows triggering on displaced impact parameters/vertices• CDF becomes a beauty/charm factory

~150 VME boards

B triggers: conventional

Suffer of low BR and not fully rec. final state

Need specialized triggers(bb) / (pp) 10-3

CDF Run1, lepton-based triggers:

Di-leptons (, PT 2 GeV/c): B J/ X, J/ Single high PT lepton ( 8 GeV/c): B l D X

Now enhanced, thanks to XFT (precise tracking at L1) :• Reduced (21.5 GeV/c) and more effective PT thresholds • Increased muon and electron coverage• Also J/ ee

Nevertheless, many important measurements by CDF 1: B0

d mixing, sin(2), B lifetimes, Bc observation, …

XFT performance

XFT: L1 trigger on tracks better than design resolution

pT/p2T = 1.65% (GeV-1)

= 5.1 mrad

XFT track

Offlinetrack

Efficiency curve: XFT threshold at PT=1.5 GeV/c

= 96.1 ± 0.1 % (L1 trigger)

53.000 J/

11 pb-

1

SVT performance

D0 K used as online monitor of the hadronic SVT triggers

I.P. resolution as planned

d = 48 m = 35 m 33 m

Efficiency

80%

90%

soon

transverse beam size

intrinsic

S/B 1

TOF performance TOF resolution (110ps)

within 10% of design value

with TOF PID

S/N = 1/40

S/N = 1/2.5

Background reduction in KK:Low PT (< 1.5 GeV/c) track pairsbefore and after a cut on TOF kaon probabilityx20 bkg reduction, 80% signal efficiency

CDF J/cross section

0<pt<0.25

GeV 5.0<pt<5.5 GeV10.0<pt<12.0 GeV

(ppJ/; pT>0; ||<0.6) =240 1 (stat) 35/28(syst) nb

Lots of charm from hadronic triggers:

Foresee a quite interesting charm physics program:• D cross sections, • CP asymmetries and Mixing in D sector, Rare decays, …

56320490

K mass

D0 K

KK mass mass

D0 KK D0

5670180 2020110

(DKK)/(DK) = 11.17 0.48(stat) 0.98 (syst) %(D )/(DK) = 3.37 0.20(stat) 0.16(syst) %

Relative Br. Fractions of Cabibbo suppressed D0 decays :

Already competitivewith CLEO2 results(10fb-1 @ (4S))

!!!!!

With ~10 pbWith ~10 pb-1-1 of “hadronic trigger” data: of “hadronic trigger” data:

O(107) fully reconstructed decays in 2fb-1

B0s mixing: expectations with

2fb-1

Signal: 20K ( only) - 75K (all) events• with SVT hadronic trigger

• BR (Ds ) = 0.3 % ; BR (Ds ) = 0.8 %

Resolution: (c) = 45 fs (with Layer00)

D2 = 11.3% (with TOF)

S/B: 0.5-2 (based on CDF I data)

5 sensitivity up to:

Xs = 63 (S/B = 2/1)

Xs = 53 (S/B = 1/2)

S.M. allowed range: 20. < Xs < 35.

Can do a precise measurement… or evidence for new physics !

xs = ms(B0s)Bs Ds, Ds

Ds , K*K,

2( m )22

1 1 S B( x )

N D Ss t

s e

Data Samples: The J/ t CDF and D0 (Run-II)

0.5M at CDF (70 pb-1) 75K at D0, completely new capability ! (40 pb-1)

Two Fully Reconstructed B-hadronJ/states at CDF &D0

BJ/ KS: CDF:220, D0:45 (Run-II) (D0 had none in Run-I)

BJ/ : CDF:53, D0:16 (Run-II)

Data Samples: B and Charm Using the high Impact Parameter (IP) (Hadronic) trigger

Select events by requiring : -2 tracks with IP>100 m - track PT > 2GeV/c - sum 2-track PT > 5.5 GeV/c

0.5M Charm decays at CDF 10-20% come from B: Great Potential for B and Charm Physics, opens at least as many avenues as J/ trigger

Data Samples: B(+)l+D decays using “hybrid” triggerSelect events with 1 lepton (PT>3 GeV/c) & 1 high IP (>120m)track:-High IP track means we can go lower in lepton PT ->Much higher than Run-I due to lower PT thresholds (x4-5 increase)

Used for:1) High statistics lifetime and mixing analyses 2) calibration samples for tagging (B+l+D) Drawback: worse vertex resolution due to missed neutrinoSome numbers:BlD0X (D0K): ~10000 events, BlD+X (D+K): ~5,000 events also Bs decays (later)

Use new “hybrid” displaced track+single lepton trigger

Decays included: Accounting for missed neutrino

Bs Dsl, Ds*l (Ds

, K*0K, +)

expect ~40K events in 2 fb-1

t is worse due to missed (K factor) :

t = 60 fs t K/K, K/K ~ 14%

If one Bs lifetime is fit in any flavour specific mode:

fit = (BsCP+2+BsCP-

2)/(BsCP++BsCP-) from which s can be determined as well

Carlo Monte from )(

)(

)(

)()(

)(

)()(

st

st

st

ssxy

st

ssxy

BP

DlPK

KDlP

BMBL

BP

BMBLct

Physics Results: Lifetimes from partially reconstructed decay

Physics Results: B, lepton+displaced track and purely hadronic data samples (have shown J/ mode already)b cl [pK] l Protons are easiest to separate using Time of Flight

Particle ID in left plot using TOF and dE/dX

b c [pK] Lifetime in hadronic, hadron+lepton modes require

correction for IP cut bias & missing Expect results after this summer

Note on B

A search for CP violation in Baryon decays is plannedusing Bp

Mixing and CP violation (CPV) at Hadron colliders Proof of principle:

Run-I, CDF were able to do 2 measurement of sin2 & competitive xd (md/) measurements: can tag b-flavours in hadron collider environment

Sin2=0.79±0.39(stat)±0.16(sys) (CDF 1996)CDF have not repeated this measurement yet…cannot compare to B-factories…

CDF: In Run-II with 40-50 x more BdJ/KS

decays can get (sin2)~0.05: D0: Similar statistics

Can’t be competitive with BaBar (insert current) and BELLE (insert current)Redo the measurement because:-It’s an important benchmark -Gives credence to other CPV measurements eg. in Bh+h- & BsJ/

Physics Results: Charm physics at CDF: Search for CP violation (CPV) in Charm decays:1) c and u quarks don’t couple to t box diagram contributions are tiny2) CPV in charm decays due to interference in decay (direct CPV) 3) SM prediction O(0.1-1%) CP violation effects in Charm Decays

How: Compare rate of Decay of D0, D0 to CP eigenstates f=K+K- and +-

0 0

0 0

( ) ( )

( ) ( )CP

D f D fA

D f D f

Method Using data from Hadronic Trigger-Collect D*±D0± : sign of tags flavour of D-Search for D0 K+K-, D0 +-, D0 +- & D0 K+K- -Correct for tracking efficiency for + vs - from D*±D0±

-Count number of decays in each mode after corrections

CPV in charm decays

…8320 D*±D0±, D0 K+K-

First CPV measurement at CDF in Run-II

93560 D*±D0±

with D0+-

Cross-check: Measure Ratio of Branching Ratios @CDF(D0 +-)/(D0 +-)=9.38±0.18±0.10% (D0 +-)/(D0 +-)=3.686 ± 0.076 ±0.036%

FOCUS: (D0 +-)/(D0 +-)=9.93±0.14±0.14% (D0 +-)/(D0 +-)=3.53±0.12±0.06%CDF accuracy is comparable and consistent with FOCUS (2003) and World average 2.88±0.15 (PDG)

ACP(D0 (+-))=2.0±1.7±0.6% (PDG 0.5±1.6%)ACP(D0 (+-))=3.0±1.9±0.6%(PDG 2.1±2.6%)

CLEO Result (2001)

ACP(D0 (+-))= 0.0±2.2±0.8%

ACP(D0 (+-))= 1.9 ±3.2±0.8%

Physics Results: Search for Flavour Changing Neutral Current decay D0+-

SM predicts a branching ratio (BR) of O(~10-13) for D0+-

Some R-parity violating SUSY models predict branching ratios upto O(~10 -6)

CDF Result: BR(D0+) 2.4x10-6 better than most recent world average:( PDG 90%CL: < 4.1 x 10-6 )

Technique:1) D0+- BR is well known ~ identical

acceptance to D0 +-

2) Use D0*± D0± to tag D0 in D0K-+ (thus no K

vs ambiguity)3) See how many s fake s per PT

5) Look for D0 +- in same sample6) Subtract D0+- faking D0+-

0 events found in 2searchwindow

Physics Results,Testing HQE: A summary of results:

D0 (240 pb-1): (B+)/(B0) = 1.093±0.021± 0.022 ps (from semi-leptonics)

CDF (240 pb-1): (B+ )= 1.660.030.01 ps, (B0 )=1.54 0.050.01 ps

B+)/Bd)= 1.080 0.042 (B+J/K+ & BdJ/K*0)

Bs)/Bd)= 0.89 0.072(Bs J/) B)= 1.25±0.26±0.10 ps (bJ/) CDF Mass Measurements: M(Bs)= 5366.01 0.730.33 MeV/c2 World’s best measurements M(B)= 5366.01 0.731.2 MeV/c2 of Bs &B masses……………BELLE (PRL 88 171801 2002)

using BdD(*)-(+), J/KS,J/K*0 and B+D0+, J/K+

B+)/Bd)= 1.091±0.023±0.014BABAR : fully reconstructed decaysBdD(*)-(+,a1

+), J/KS,J/K*0 and B+ D0+, J/K+

B+)/Bd)= 1.082±0.026±0.012 BABAR : partially reconstructed decays(BD,D* l )B+)/Bd)= 1.064 ±0.031 ±0.026

HQE Predicted B Lifetime hierarchy :

Bc << b0 ~ b < Bd ~ Bs < B- < b-

Physics Results: Charm physics at CDF: Search for CP violation (CPV) in Charm decays:

1) c and u don’t couple to t box diagram contributions are tiny2) CPV in charm decays due to direct CPV SM~O(0.1-1%) CPV, good test of SM !How: Compare N(D0), N(D0)to CP eigenstates K+K- & +-

0 0

0 0

( ) ( )

( ) ( )CP

D f D fA

D f D f

Data from SVT: 1) Find D*±D0± : sign of tags flavour of D, 2) Find D0 K+K-, D0 +-, D0 +- & D0 K+K-

1) Cross-check:Ratios of BRs (@CDF):(D0 +)/(D0+)=9.38±0.18±0.10% & (D0 +-)/(D0 +-)=3.686 ± 0.076 ±0.036FOCUS: 9.93±0.14±0.14% & 3.53±0.12±0.06% CDF consistent with FOCUS & PDG 2.88±0.15

First CPV result at CDF in Run-II

AD0 +-

=2.0±1.7±0.6% AD0+-

=3.0±1.9±0.6%CLEO Result (2001) & PDG

AD0+- = 0.0±2.2±0.8%

AD0+- = 1.9 ±3.2±0.8%

(0.5±1.6 & 2.1±2.6%)

Physics Prospects: CP violation in Bh+h- decays determining angle CDF)

Bh+h- from hadronic triggerIncludes B Bs K+K-

Bs K, and Bd K

Monte-Carlo:Bd Bs K+K- Bs K,

& Bd K (From Monte-Carlo)-all pile up

Must disentangle each mode from signalWe (will) use: -dE/dx based K and ID -Kinematical variable: M vs =(1-p1/p2)q1

-Width of signal -Frequency of oscillation in CP asymmetry

Physics Prospects: CP violation in Bh+h- decays determining angle CDF), Method:

u-b

W

u

ud-

b dW

u,c,t

b su,c,t bW

us

W

Five observables,

Four unknowns:d=ratio of penguin/tree hadronic matrix elementsphase of d = weak phases

Constrain Sin2 from B-factories, & CDF/D0 results and measure

Tree and penguin graphs for B & Bs K+K-

-CP Asymmetry in B = Sin2() (without penguin) -CP Asymmetry in Bs K+K- = Sin2without penguin) -Assume SU(3) symmetry: replace sd Hadronic matrix element ratios : penguin/tree same for both modes

Tree > penguin in B vice-versa in BsK+K-

Proposed by: R.Fleischer, PLB459 1999 306

Physics Prospects: CP violation in Bh+h- decays determining angle CDF)

Numbers from 65 pb-1 sample & 1.16 dE/dX separationUpdate from re-calibrated dE/dX (1.4) & 180 pb-1 in progress

Yields (Results from 65 pb-

1)BdBdKBsKBsK+K- BsK+K- First Observation !!)

M vs a for each Bh+h- mode

Sanity check: Measure Ratio of Branching RatiosCDF : (Bd-)/(Bd K+-) = 0.26 ±0.11±0.055, PDG: 0.13 0.010.29

0.12 0.02

Fleischer method: Expect (2fb-1): () =±10(stat) ±3(syst SU(3) breaking)

Ratio of BRs along with ACP(Bd ) from B-factoriesHelps constrain

hep-ph/0404009

U-Spin relationship

SM check by comparison with ACP in Bd

58°<<72°

BR

(Bs

K+K

-

) BR

(Bd+-

)

ACP(Bd+-)dir

Physics Results, Testing HQET: lifetime, mass, from fully reconstructed B decays modes, Technique :

Data from J/ di-muon trigger or High IP trigger: - Reconstruct vertex - Calculate decay proper time, mass & errors- Mass:fit mass distribution only- Fitting for Lifetime:Fit mass and lifetime distributions in single step

Technique applied to several decays : B+ J/ K+, B0 J/ K0* (K0* K), Bs J/ ( KK) & bJ/ (p)…etc

( , ) . ( , ) (1 ). ( , )

( , ) 1

total s signal s backround

total

F m t f F t m f F t m

F m t dmdt

Probability Density Function and normalization:

-Those Decays selected usingSVT trigger have biased c(Also lepton+high IP track data@CDF)-Fix bias and then measureLifetimes in Bs Ds

+-, and other purely hadronic decays

High IP track selection efficiency

Physics Results,Testing HQE:Lifetime, mass summary:

D0 (240 pb-1): (B+)/(B0) = 1.093±0.021± 0.022 (from semi-leptonics)

CDF (240 pb-1): (B+ )= 1.660.030.01 ps, (B0 )=1.54 0.050.01 ps

B+)/Bd)= 1.080 0.042 (B+J/K+ & BdJ/K*0)

Bs)/Bd)= 0.89 0.072(Bs J/) B)= 1.25±0.26±0.10 ps (bJ/) CDF Mass Measurements: M(Bs)= 5366.01 0.730.33 MeV/c2 World’s best measurements M(B)= 5366.01 0.731.2 MeV/c2 of Bs &B masses……………BABAR : exclusive decays BABAR : inclusive decays B+)/Bd)= 1.082±0.026±0.012 B+)/Bd)= 1.064 ±0.031 ±0.026

BELLE B+)/Bd)= 1.091±0.023±0.014

HQE Predicted B Lifetime hierarchy :

Bc << b0 ~ b < Bd ~ Bs < B- < b-

-Projection: (Bs)/Bd) ) & (Bd)/b)) <1% at 2fb-1

-Current (Bu+)/Bd

0) ) surpasses theoretical accuracy

-Measurements test vertexing & tracking: Crucial for MBs and CPV

Physics Results: Rare B decays: B s(d)

-No observed excess -Expected backgrounds (events): 1.050.3 (Bs) and 1.07 0.31 (Bd)-Observed 1 event for both modes branching ratio limit is possible-SM Prediction BR~10-9

Bs result surpasses previous worlds best result (by x2 CDF)

BR limits vs. luminosity

Bd result: bit better than Belle (1.6x10-7) and BaBar (2.0x10-7)

Submitted to PRL

BR Upper Limit at 95% CL 7.5x10-7 (Bs )1.9x10-7 (Bd )

BR Upper Limit at 90% CL 5.8x10-7 (Bs )1.5x10-7 (Bd )

Rare Decays: Bsbranching ratio:

Calculate Branching ratio using corrected Ncorr(Bs J/:

s ss corr

s

N(B ) (B ). ( / )ε(ψφ)BR(B φφ)

N(B ) ε(φφ) ( )

φφ BR ψφ BR J

ψφ BR K K

s ss

s

N(B ) (B ). ( / )ε(ψφ)BR(B φφ)

N(B ) ε(φφ) ( )

φφ BR ψφ BR J

ψφ BR K K

1) Approach: calculate branching ratio by using N(Bs J/)in the same data (SVT triggered) sample:

SM Prediction for branching ratio: 3.7x10-5 hep-ph/0309136BR= (1.4 ± 0.6 (stat) ± 0.2(syst) ± 0.5 (BR))x10-5

Upper Limit : BR= (1.4 ± 0.6 (stat) ± 0.2(syst) ± 0.5 (BR))x10-5

1) All BRs are taken from PDG2) Efficiencies calculated from MC 3) N(Bs J/) is corrected for: a) Reflections from Bd J/K*(892) b) Requirement of a muon match (check of signal in SVT data)

Physics Results : Hadronic Moments Calculating : D, D* are known , measure only f**, contains wide and narrow D**0 and non-resonant part. Reconstruct only B- D**0 l- (0s not possibe @ CDF). Find and D**0 consistent with coming from B (vertex), Mass<5.3 GeVD**0 D+, D*+, D*00, reconstruct or use Isospin for Mass pdf

1 sl

sl H

d

ds

Using Lepton+High IP data:A) D**0 D*+ -

B) Can’t do D**0 D0 0

But = 0.5A & same shape

C) D**0 D+ - D) D*+ D0 + E) D*+ D+ 0 Can’t do: Feed-

down to D+ - & is corrected for.

F) D**0 D*0 0 Can’t do but = 0.5.A (same shape)

Physics Results: Hadronic Moments analysis

42

12

**2

22**1

69.030.1

16.083.5

GeVmmm

GeVmm

D

D

D**0 mass distribution…. ….gives moments wrt D**0 only

Moments from all D, D*

And finally from M1 & M2 we get:

Best single measurementOf M1 M2 in the world !

Physics Prospects: CP violation in Bh+h- decays determining angle CDF), Method:

u-

bW

u

ud-

b dW

u,c,t

b su,c,t bW

us

W

Tree > penguin in B vice-versa in BsK+K-

MC

Lumi~180pb-

1

Bh+h- from hadronic trigger

Problem: Separating Bd Bd Bs

Bs Use M vs =(1-p1/p2)q1, dE/dX, to separateBd Bd Bs Bs in the futureWill use oscillation frequencies as well……

dE/dx check: Use D*±D0, D0 K

Four unknowns In Asymmetry(t):d=ratio of penguin/tree hadronic matrix elementsphase of d = weak phases Constrain Sin2 from B-factories, & CDF/D0 results and measure by fitting asymmetry Proposed by: R.Fleischer, PLB459 1999 306

Toward Bs Mixing: Proof of principle CDF (Run-II) Md

First Run-II result: Bd-Bd oscillations using same side tagging (SST)Look for fragmentation from B, track with lowest relative PT to B -Use B+J/ K+ (J/ data) & B+D0+ (SVT data) to tune

tagging -Use B0J/ K*0( K)and B0D to measure md

Flavour Tagging-Look for fragmentation from B-Calculate Pt

rel variable-Want maximally collinear B and -Pick candidate with lowest Pt

rel -B flavour is correlated with sign

CDF Run-I md (all methods) = 0.495 ± 0.026 ± 0.025 ps-1

Physics Prospects: CP violation in Bh+h- decays determining angle CDF), Method:

u-

bW

u

ud-

b dW

u,c,t

b su,c,t bW

us

W

Tree > penguin in B vice-versa in BsK+K-

MC

Lumi~180pb-

1

Bh+h- from hadronic trigger

Problem: Separating Bd Bd Bs

Bs Use M vs =(1-p1/p2)q1, dE/dX, to separateBd Bd Bs Bs in the futureWill use oscillation frequencies as well……

dE/dx check: Use D*±D0, D0 K

Four unknowns In Asymmetry(t):d=ratio of penguin/tree hadronic matrix elementsphase of d = weak phases Constrain Sin2 from B-factories, & CDF/D0 results and measure by fitting asymmetry Proposed by: R.Fleischer, PLB459 1999 306

Examples of decays: Accounting for missed neutrino:

Bs Ds-l+, Ds*-l (Ds

++, K*0K+, ++)

Bu- D0l-, D0l- X (D0 +K-)

Advantage: Very high statistics

Drawback: t is worse due to missed (K factor)

However: Large numbers provide opportunities for lifetime & mixing

Physics Results Testing HQE: Lifetimes from partially reconstructed decays

Data are selected using high PT leptons (D0) & lepton+high IP track (CDF)

D0: Charged to Neutral B-Meson Lifetime Ratio: +/0

-B D*(2010)-X decays: mostly Bd

-B D0X decays: mostly Bu±

-Calculate ratio of events/lifetime bin-Account for all decays BRs (PDG) -ratio of events expected : ~N+/N0 ~e-(+/0-1)t (K-factor)t

D0 Result: +/0 = 1.093 ± 0.021 (stat) ± 0.022 (syst) Competitive with worlds best results

0

0

( ) ( ) ( ) ( )

( ) ( )

( ) from Monte Carlo

( )

xy u u xy u u

t u t

t

t u

L B M B L B M Bct K

P B P l D

P l DK

P B