1

B Physics at D0: An update

Vivek JainCornell University

Oct 1, 2004

2

Outline

Introduction D0 detector Recent Results

New states Rare decays Lifetimes Mixing

Conclusions

3

4

Why B physics? Understanding structure of flavour dynamics is

crucial 3 families, handedness, mixing angles, masses, … any unified theory will have to account for it –

Weak decays, especially Mixing, CP violating and rare decays provide an insight into short-distance physics

Short distance phenomena are sensitive to beyond-SM effects

Test bed for QCD, e.g., form factors, calculations of B hadron lifetimes, spectroscopy

5

B physics at the Tevatron

At Ecm = 2 TeV

At Z pole

At Υ(4S)

All species produced,

bbbpp 150)(

nbbbee 7)(

nbbbee 1)(

...,, bsc BB

Environment not as clean as at electron machinesLow trigger efficiencies

6

B Physics Program at D0

Unique opportunity to do B physics during the current run Complementary to program at B-factories (KEK, SLAC, CLEO..)

mixing, Rare decays: Large tanβ SUSY models enhance rate

Beauty Baryons, lifetime, … expt: 0.80±0.06 (SL modes), theory ~ 0.95

, , B lifetimes, B semi-leptonic, CP violation studies Quarkonia - production, polarization …

SB SB

CB

,ψ/J

b

SS /

b production cross-section: In Run I, measd. Rates x(2-3) higher

)(/)( 0db B

**B

b

7

DZero Detector

SMT H-disks SMT F-disks SMT barrels

Muon system with coverage |η|<2 and good shielding

TrackersSilicon Tracker: |η|<3Fiber Tracker: |η|<2

Magnetic field 2T

8

8 Layers: Axial, Stereo (± 3°)Radius: 20-50 cm

Readout by VLPC:High QE, very low dark noiseExcellent PE resolutionEach pixel has 1mm radius – well matched to fiberOperated at 8-9 (± 0.05)°K

Good S/N. Signal ~ 5-9 pe

Fast enough to be in L1 trigger

CFT

9

VLPC performance

Signal ON: LED wasset to ~ 2 pe

10

πKD μX,DB 00

2.2)(GeV,2)( TpAll tracks

Analysis cuts – pT>0.7 GeVσ(DCA)≈53μm @ Pt=1GeVand better @ higher Pt

data

11

pT spectrum of soft pion candidate in D*D0

~100 events/pb-1

12

Excellent Lepton Acceptance

Muon ID:

Tp

MC: πμX, DDB ss

of reconstructed muon

Overall efficiency (from data)plateaus at about 85-90%

- at pT 4.5 GeV

pT 3.5 GeV

- at pT 2.5 GeV

6.0

2.16.0

2.1

Muon system in Level 1

13

Calorimeter goes out to

Low pT electron ID is in progress

At present, we can detect electrons with pT>3 GeV and Average efficiency is about 75% Working to extend to higher values of and lower pT threshold – use for tagging initial state flavour

1.1

Electron ID:

4

14

All trigger components have simulation software

15

Triggers for B physics

Robust and quiet di-muon and single-muon triggers Large coverage |<2, p>1.5-5 GeV – depends on Luminosity

and trigger Variety of triggers based on - Muon purity @ L1: 90% - all

physics! L1 Muon & L1 CTT (Fiber Tracker) L2 & L3 filters

Typical total rates at medium luminosity (40 1030 s-1cm-2) Di-muons : 50 Hz / 15 Hz / 4 Hz @ L1/L2/L3 Single muons : 120 Hz / 100 Hz / 50 Hz @ L1/L2/L3 (prescaled)

Current total trigger bandwidth 1600 Hz / 800 Hz / 60 Hz @ L1/L2/L3

16

17

Recent Results

Many new analyses used ~ 250-350 pb-1

Single muon triggers have variable prescales, non-trivial to determine luminosity for analyses using these triggers

Have more data on tape, but not yet analyzed

Details at: www-d0.fnal.gov/Run2Physics/ckm/

18

Basic particles

Plot is forillustrativepurpose

19

Large exclusive samples

~ 350 pb-1

Impact parameter cuts

7217±127

2826±93

624±41

20

~ 250 pb-1

Will reprocess w/ trackingoptimized for long-lived part. (yield will ~50%)

No IP cuts:Use for lifetime

337±25

Bs

Λb

21

Observation of X(3872)

In 2003, Belle saw a newparticle at 3872 MeV/c2, observed in B+ decays:B+ K+ X(3872), X(3872) J/ + -

Belle’s discovery has been confirmed by CDF and DØ.

DØ (accepted by PRL) 522 ± 100 events

M = 0.7749 0.0031 (stat) 0.003 (syst) GeV/c2

5.2 effect

22(Estia Eichten) J_PC

Charmonium

23

What kind of particle is the X ?

- charmonium ? 1 ³D3, 2 ³P2 …

- an exotic meson molecule ?

- something else ?

Compare X candidatesto (2S), e.g.

- split into two || regions

- decay length, isolation, helicity

24

No significant differences between(2S) and X have been observedyet.

This comparison will be moreuseful once we have models ofthe production and decay of, e.g.,meson molecules that predictthe observables used in thecomparison.

Observation of the charged analog X+ J/ + 0 would rule out charmoniumObservation of radiative decays X c would favour charmonium Belle’s results rule out 1 ³D3, 2 ¹P1, ³D2, ¹D2, 0-+, 1++ Use Dzero’s calorimeter to identify low energy 0 and : work in progress.

pT>15

|y|<1

Hel(ππ)<0.4 dl<0.01 cm

Iso=1

Hel(μμ)<0.4

25

Spectroscopy: L=1 B (and D) mesons

For Hadrons with one heavy quark, QCD has additional symmetries as

(Heavy Quark Symmetry)

Spin of the heavy quark decouples and meson properties are given by the light degrees of freedom

Each energy level in the spectrum of such mesons has a pair of degenerate states:

QCDQm

Qqq sjJj

,Lsj qq

26

For non-strangeL=1 Charm mesonsjq = 1/2, 3/2 havebeen seen

Belle hep-ex/0307021

MeV25

MeV300

Lessons from charm (I)

The wide states were observedvia Dalitz plot analysis in

(*)DB

27

D** at D0

Preliminary result on product branching ratioBr(B {D1

0,D2*0} X) Br({D10,D2*0} D*+ -)

= 0.280 0.021 (stat) 0.088 (syst) % measured by normalizing to known Br (B D*+ X)

28

Lessons from charm (II) – Ds**

jq = 1/2 below DK threshold, decay to

Mass/widths unexpected!

Maybe B** or Bs** have similar behaviour

For L=1 Ds mesons,

preferred decay mode:DK

jq = 3/2 -> DK, D*K

(*)0(*) / ss DD

Eichten

29

Previous results on B**

Previous experiments did not resolve the four states:

<PDG mass> = 5698±8 MeV

Theoretical estimates for M(B1)~ 5700 - 5755 and for M( ) ~ 5715 to 5767. Width ~ 20 MeV

Experiment B reconstruction BJ mass (MeV) BJ width

ALEPH exclusive 5695±18 53±16

CDF (μD)+π 5710±20 -----

DELPHI inclusive B + π 5732±21 145±28

OPAL inclusive B + π 5681±11 116±24

Probably not the naturalwidth of these states

*2B

30

Signal reconstruction (I)

Search for narrow B** - Use B hadrons in the foll. modes and add coming from the Primary Vertex

Since ΔM between B**+ and B**0 is expected to be small compared to resolution, we combine all channels (e.g., ΔM for B+/B0 = 0.33±0.28 MeV)

KJB /

KKKJBd0*0*0 ,/

000 ,/ KKJBd

7217±127 events

2826± 93 events

624± 41 events

31

Signal Reconstruction (II)

Dominant decays modes of ( forbidden by J,P

conserv.) (ratio of the two modes expected to be 1:1)

To improve resolution, we measure mass difference between and B, ΔM

BBBB **1 ,

BBBB ***2 ,

BB *2

B

*21, BB

*21, BB

32

Signal reconstruction (III)

Now, ΔM(B* - B) = 45.78±0.35 MeV – small Thus, if we ignore , ΔM shifts down ~ 46 MeV,

MeVBMBMBBM 46*)()()( *

2*2

We get three peaks: = M( ) – M(B*) – 46 MeV = M( ) – M(B*) – 46 MeV = M( ) – M(B) - in correct place

1B*2B*2B

123

33

BB *2

BBBB ***2 ,

BBBB **1 ,

From fit:

N = All B**

536±114events

First observation of the separated states

~7σ signif.

Interpreting the peaks as:(98)

273±59 events

131±30 events

34

B0**

B±**

Consistency checks:

required to have large Impact parameter signific.relative to Primary vertex – No Signal (as expected)

32±36 events

35

Results of fit - Preliminary

21 /)(7)(45724)( cMeVsyststatBM

21

*2 /)(9.3)(7.76.23)()( cMeVsyststatBMBM

221 /)(9)(1223 cMeVsyststat

)(21.0)(11.051.01 syststatf

36

sB

Standard Model predictions

Exptl. Results 90% (95%) CL

37

Beyond Standard Model

First proposed by Babu/Kolda as a probe of SUSY (hep-ph 9909476)

Branching fraction depends on tan(β) and charged Higgs mass

Branching fraction increases asin 2HDM (MSSM)

)(tantan 64

Other models also have enhanced rates, e.g.,

Dedes, Nierste hep-ph 0108037mSUGRA

38

Experimental challenge: (L 200 pb-1)

39

Optimization Procedure – “blind” analysis

~ 80 pb-1 of data was used to optimize cuts After pre-selection, three additional variables were

used to discriminate bkgd. from signal - Isolation : Since most of b-quark’s mom. is carried by

the B-hadron, track population around it is low

Decay Length significance: Lxy/δLxy – remove combinatoric background, e.g., fake muons

Pointing angle: Angle, α, between B_s decay vector and B_s momentum vector

))1(|)(/(||)(|

Bi

i RpppI

40

Pointing angle < 0.20 (rad)

Result of optimization

δLxy/ δL > 18.5

Isolation > 0.56

Background prediction from sidebands in (MB ± 2σ): 3.7 ± 1.1 events

Punzi (physics/0308063)

41

Opened the box (July 8’ 04)

Nothing remarkable about the four events – look like background!

(L = 240 pb-

1)

42

Calculate upper limit (I)

To calculate limit on branching fraction, normalize to

KJB /

Bs

Bd

dBubBsb

Bs

BK

B

uls

Rff

JB

N

NB

.)/(

)/().(..)

,

21 BBBr(

0.270±0.034 (PDG)

Since our signal region overlaps Bd, can have contaminationR: theoretical expectation for ratio of Br. frac. of Bd /Bs - set R=0If limit will be better

Feldman-Cousins

PDG

MC: 0.229±0.016 MC

0R

43

Upper Limit - Preliminary

The 95% (90%) C.L. upper limit:

)108.3(106.4)( 77 sBBr

If we use Bayesian approach, we get 4.7 (3.8)

Currently, the most stringent limit on this decay channel

44

Implications of this resultExcluded by D0 Run II 240 pb-1

Dermisek et alHep-ph 0304101

Dark Matter andMinimal SO10 with soft SUSYbreaking

sB

Allowed by Dark Matterconstraints

Contours of constant)( sBBr

4.6E-7 (95%CL)

45

Observation of Bc

Last of ground state mesons to be definitively observed!

Theory: Lifetime 0.3-0.5 ps

Theory: Mass 6.4 GeV ±0.3

Only previous evidence CDF RunI result

20.4 signal+6.2- 5.5

Mass: 6.4±0.39±0.13 GeV

0.46 0.03 ps+0.18

- 0.16

46

Take advantage of easy-to-trigger-on final state – events come via the dimuon triggers

Bc+

+

+-

PV

Select 231 J/X candidates

Background estimated with J/+track data control sample, separated into prompt and non-prompt components

47

Do combined likelihood fit to invariant mass and pseudo-proper time distribution:

#signal: 95±12±11

Mass:

5.95 ±0.34 GeV+0.14

-0.13

Lifetime:

0.448 ±0.121 ps+0.123

-0.096

48

Background-only fit:

2log(likelihood) is 60 for 5 degrees of freedom

49

Other properties:

b

b

cc

Bc

Forms weakly decaying charmed hadron

Probability 4th within ±90 degrees of Bc candidate = 5±2%

Probability 4th within ±90 degrees of background = 1%

50

Lifetimes of B hadrons

Use modes with J/ψ final states, semi-leptonic decays

Predictions available from theory via OPE calculations

These calculations are rooted in QCDExpansion is in inverse powers of heavy quark massPredictions are semi-quantitative for CharmFor B-hadrons, predictions are on much firmer footing

51

52

“D0 sample”: + K+ - + anything

B+ 82 % B0 16 % Bs 2 %

“D* sample”: + D0 - + anything

B+ 12 % B0 86 % Bs 2 %

Estimates based on measured branching fractions and isospin relations.

(B+)/(B0) from semileptonic decays

Novel idea: Signal with Imp. Param cuts

53

Group events into 8 bins of Visible Proper Decay Length (VPDL):Measure ri = N(+ D*-)/N(+ D0) in each bin i.

Minimize:

Additional inputs to the fit:

- sample compositions (previous slide)

- K-factors (from MC) – missing particles

K = pT(D0) / pT(B) [separately for different decay modes]

- Relative reconstruction ε for different B decay modes (from MC)

- Slow pion reconstruction ε [flat for pT(D0) > 5 GeV (one of our cuts)]

- Decay length resolution (from MC)

- (B+) = 1.674 0.018 ps [PDG] – Fix in fit

)(

))(.(2

22

i

eii

r

krNr

one example VPDL bin

BD

TT MpLVPDL )/(

1)/( 0 k

54

Preliminary result:

(B+)/(B0):1.093 0.021 0.022 (stat) (syst)

Syst. dominated by:

- time dependence of slow reconstruction eff. - relative reconstruction efficiency CY

- Br(B+ + D*- + X) - K-factors - decay length resolution differences D0 D*

The prelim. DØ meas. is one of the most precise results Not updated

Adding more data

55

56

/Jb

ps (sys) 0.043 (stat) 217.0179.0

221.1 b

sd KJB /

Also did,

2D fit: Mass andLifetime (100)

57

Summary of Λb results

World Average

1.229±0.080 ps

0.798±0.052

Theory: 0.90±0.05

World Average uses semi-leptonic modes

58

ps (sys) 0.020 (stat) 098.0090.0

444.1

sB

Most existing meas. use SL mode

/JBs

Single best measurement

*/ KJBd

Also did,

2D fit: Mass andLifetime

59

Summary of Bs results

World Average

1.461±0.057 ps

0.951±0.038

Theory: 1.00±0.01

<World> contains final states with different amts. of CP e-states

60

2nd order weak transition

Mixing is high priority SB

S

dtd m

mV

ρ<0 disfavoured by current limit on Δms (>14.4/ps)

00SS

LS BqBpB

00SS

HS BqBpB

LHS MMm

HLS

61

Bs CP =+1 & CP = -1 Lifetimes

B0sJ/ψ φ unknown mixture of CP =+1 & CP = -1 states

In Standard Model s/s may be as large as 0.1 ( )

Γs = ( ΓLight + ΓHeavy)/2 ; ΔΓs = ΓLight - ΓHeavy

In the case of untagged decay, the CP – specific terms evolve like:

CP - even: ( |A0(0)|2 + |A||(0)|2 ) exp( -ΓLightt)

CP - odd: |A┴(0)|2 exp( -ΓHeavyt)

Flavor specific final states (e.g. B0slDs ) provide:

Γfs = Γs - (ΔΓs)2 / 2Γs + Ό ( (ΔΓs)3 / Γs 2 )

sm

DZ – Beauty’03

62

Bs Lifetimes, transversity variable θT

The CP-even and CP-odd components have different decay distributions.

The distribution in transversity variable θT and its time evolution is:

d(t)/d cosθT ∞ (|A0(t)|2 + |A||(t)|2) (1 + cos2θT) + |A┴(t)|2 2 sin2θT

3 linear polarization states: J/ψ and φ polarization vectors: longitudinal (0) to the B direction of motion;

transverse and parallel (||) and (┴ ) to each other

MC distributions for CP = +1 & CP= -1 for accepted events (D0)

DZ – Beauty’03

In progress

63

)cos( tmPP

PPA s

MU

MU

How to measure Δm

64

In search of BS oscillations

(“Amplitude method”)

)cos(12

tmAe st

P

Fit data to

Fit for A as a function of ms

Measurement: A = 1Sensitivity: 1.645A = 1 (95%)Limit: A < 1 - 1.645A (95%)

Current limit : ms > 14.4 ps-1 @95% CL

65

Compare A for Δm=15 ps-1

66

Significance of mixingmeasurement BS

Stm

eDN

2/2)(

2

2

We need:

Final State reconstructionAbility to measure B decay lengthB flavour at decay and production

67

Use flavour-specific decays to get flavour of B at decay

To get flavour of B at production use

Flavour tagging

b-hadronTrigger leptonFragmentation

pionB

PV D

neutrino

Same side

Lxy

Soft lepton

Jet charge

Opposite side

68

Require |Q| > 0.2

MC

b0Q (B+ MC)

69

Data sample split into two sets:1) Tagged by soft muons (SLT)2) Tagged by combined jetQ+SST algorithm

Combined algorithm produces non-zero answer if:– Event not tagged by SLT– At least one of jetQ and SST gives a non-zero answer– jetQ and SST give same answer ( better dilution)

Combined tags analysis - Bd

200pb-1

70

Combined tagger result

Simultaneous fit to SLT and jetQ+SST asymmetries

SLT

jetQ+SST

md=0.456 0.034 (stat) 0.025 (syst) ps-1

D0 = (44.8 5.1) % SLT D0 = (14.9 1.5) % jetQ+SST

D= (27.9 1.2) % jetQ+SST

= (5.0 0.2) % SLT = (68.3 0.9) % jetQ+SST

Preliminary results:

Chief systematics:• D* sample composition• D** pion tagging probability• Charged B dilution determination

200pb-1

71

One can reconstruct in hadronic and semi-leptonic modes

Hadronic modes, e.g., Pros: Very good proper time resolution Cons: Low branching fraction ( ), triggers

Semi-leptonic modes, e.g., Pros: Large Branching fraction , triggers Use both Muon & Electron final states Cons: Poorer proper time resolution

SB

(*)SS DB

(*)SS DB

%5.0

%10

72

X SS DB

SL modes have large yields

DS BR= (3.60.9)%

~ 9481 events in 250pb-1

73

BS DS X

Other DS decays are being studied too

BR= (3.30.9)%(BR comparable to Ds )

But larger backgrounds D- K+ - -

D- K* - non-resonant D- K+ - -

~ 4933 events in 200 pb-1

Significant increase in total BS yield

KKDs0*

74

μ+

π -

K+K-

φ

D-S

BS

μ+

Tagging muon Y, cm

X, cm

Mixed BS candidate in Run 164082 Event 31337864

Two same sign muons are detected Tagging muon has η=1.4 See advantage of muon system with

large coverage MKK=1.019 GeV, MKKπ=1.94 GeV PT(μBs)=3.4 GeV; PT(μtag)=3.5 GeV

75

Studying electrons as an initial state flavour tag Hadronic modes – Bs -> Ds* pi

New triggers online – very effective for hadr. Decays

If nature is kind, and Δm is on the low side, we could have a shot at it with the SL mode

Some upgrades are planned: Layer 0 – new Silicon layer at r ~ 2.5 cm. Significant improvement in proper time resolution (mid-2005) Double trigger bandwidth/reconstruction farms and write more data to tape – in proposal stage

Progress report:

76

Conclusions and Outlook

Lot of progress in the previous year

Accelerator performing reasonably well. Expect 500 pb-1 by the end of the calendar year

B physics group producing competitive results

Exciting times ahead

77

Backup slides

78

Elements of the CKM matrix can be written as: λ – Cabbibo angle (~0.22), A (~0.85),

Magnitude of CP violation is given by η

b

s

d

V

b

s

d

VVV

VVV

VVV

b

s

d

CKM

tbtstd

cbcscd

ubusud

ˆ

'

'

'

))2/1((, 2

Need to precisely determine the CKM matrix

79

80

Unitarity of the CKM matrix leads to

relationship between various terms One such relation:

0*** tbtdcbcdubud VVVVVV

81

CA:

BA:

If CKM matrix is unitary, leadsto triangles in the ρ, η planeVtd

Vub

Vcb

82

Study of B hadrons yields B mixing: η can be inferred from CP violation Within the SM, CP conserving decays sensitive to

> 0 can be inferred from limit on Bs mixing

Complementary meas. of η, from New phenomena might affect K and B differently

,,|,/||,| tstdcbubcb VVVVVtstd VV ,

|||,/||,| tdcbubcb VVVV

|| tdV K

can tell if η is non-zero

83

Winter 2004HFAG avg.(fit does not include results onSin(2β))

84

SMT regionηmax = 2.5

SMT+ CFTηmax = 1.65

Pre-shower detectors help in e-ID

Barrels and Disks

85

6 barrels: 4 layers SS+DS, 2/90° stereo |z|<0.6 m, r = 2.7-10 cm

12 central F disks: DS, 144 wedges, stereo

4 forward H disks: 96 wedges, z: 1.1/1.2 mr: 9.5-20 cm

15 5.7

Tracking to η ~ 3 (θ ~ 6°)

793K channels, rad hard to 1 MRad ~ 2-3 fb-1

S/N > 10, 1 MIP ~ 25 ADC countsHit resolution ~ 10μ

SMT

86

• J/mass is shifted by 22 MeV• Observe dependence on Pt and on material crossed by tracks• Developed correction procedure based on field & material model • Finalizing calibration of momentum scale using J/Ks, D0

NOT yet used

87

88

Track triggers very important for B physics - Trk/muon match at L1 - Trks are fed to L2 Silicon track trigger - Trk/Pre-shower match

89

Silicon Track Trigger is being commissionedTrigger is online – as yet not used for physics

CFT inner layer

CFT outer layer

SMT barrels

1-mm road

Performs final silicon cluster filtering and track fitting– Lookup table used to convert

hardware (e.g., channel, etc.) to physical coordinates ( )

– 8 300-MHz 32-bit integer Texas Instruments DSPs perform a linearized track fit

– Fit using precomputed matrix stored in lookup table

0)( rr

br

,r

90

Accelerator performance

Run Ib Run IIa Run IIb

# bunches 6X6 36X36 140X133

(TeV)1.8 1.96 1.96

1.6E31 8E31 2-5E32

Bunch x-ing(ns)

3500 396 132(?)

Int./x-ing 2.8 2.4 2-5

s12 scm L

Currently 12

inst scm31E64 L 1pb280LHave

91

92

Basic Particles

93

Inclusive B lifetime using X0 DB

112 - pbL μm)stat(25438c 2472PDG

Standard technique – no IP cuts. Poor S/B

94

95

Aside: Where do the B’s go?

Factor # events for 2 fb-1

3E11

2 b quarks/event 6E11

6E10

1.8E8

7.2E6

3.6E6

Single μ Trig. Eff < 1%

<3.6E4

Reco. Eff. <10% <3.6E3

bbb 150)(

10.0)( (*) sBbB

003.0)( ss DBB

04.0)( sDB

5.0)( KKB FlavourTag μcomesfor free

96

For L=1, get two pairs of degenerate doublets,

jq=1/2, J=0, 1 -

jq=3/2, J=1, 2 -

HQS also constrains the strong decays of these states

jq = 1/2 decay via S-wave, hence expected to be wide jq = 3/2 decay via D-wave, hence narrow

'*0 , BB

*21, BB

These four L=1 statesare collectively known as B** or JB

Strong decays

For L=0, two states withjq=1/2, J=0, 1 - B, B*

97

Lessons from Charm (III)

For charm mesons, M(D*)-M(D) ~ 140-145 MeV For bottom, M(B*)-M(B) ~ 46 MeV Theory: Splitting within a doublet has 1/m_Q

corrections

M( )-M( ) ~ 32-37 MeV (jq=3/2 doublet)

Could expect this to be ~ 10-15 MeV for M( )-M( )

For non-strange charm, M(D**)-M(D) ~550-600 MeV

Would expect similar behaviour for B mesons

*2D 1D

*2B 1B

98

Signal Reconstruction (V)

We fit the ΔM signal with 3 relativistic Breit-Wigner functions convoluted with Gaussians

N: Number of events in the three peaks : Fraction of in all events : Branching fraction of From theory fix and From MC fix resolution of ΔM=10.5 MeV

))),(*)1(),(*)(1(),(*.( 2322221111 GfGffGfN

**

2 BB 21 5.02 f

1f

2f1B

99

Sample composition

B meson lifetimes and branching rates from PDGK-factor distributions, decay length resolution, reconstruction efficiencies from MC

86% B0

12% B+ 2% BS

16% B0 2% BS

82% B+

D* sample

D0 sample

100

2D lifetime fits

101

102

Quarkonia at D0

Have older results on J/Psi production. Will update - Cross-section as a function of pT and η

Started to look at Upsilon production characteristics - We presented a preliminary pT distribution at QWG’03 and more recently at PHENO’04 - Next step is to determine production absolute cross-section and polarization studies

103