B, ?B and Charm results from the Tevatron

1
B, ?B and Charm results from the Tevatron
Physics in Collision Zeuthen, June 27 2003

• Farrukh Azfar, Oxford University (CDF)

2
Overview of this presentation

• Tevatron performance Beauty Physics at the
  Tevatron
• 2) CDF and D0 detectors and triggers
• Data from various Triggers at CDF and D0
• Physics Results Masses and Lifetimes of B
  hadrons
• Tests of Heavy Quark Expansion (HQE)
• 4) Physics Results Charm masses, search for
  CP violation (CPV) Flavour Changing Neutral
  Current (FCNC)
• 5) Physics Prospects CP violation, Bs mixing
  (xsDms/G) and Bs width difference (DGs)
• 6) Conclusion and Summary

3
Tevatron pp collider upgrade performance
Run-I (1992-1996) -Accumulated Ldt110
pb-1 Run-IIa -Goals are Ldt2fb-1 (x20 Run-I)
Run-II Tevatron Upgrades Main Injector -New
Injection stage for Tevatron -Higher proton
intensity -Anti-proton transfer efficiency
increased -Anti-proton recycler (work in
progress)
Performance Improvement -Collision rate 3.5 ms
? 396 ns -6x6 bunches ? 36x36 bunches -Center of
Mass energy 1.8 ? 1.96 TeV/c2 -Peak luminosity
2.4x1031 ? 4.4 x1031cm2s-1 (Below target by x4,
steadily improving)
4
Data taking performance CDF D0
CDF integrated luminosity -Delivered 230pb-1 of
which -175pb-1 to tape, of which -70 pb-1 has
important systems on (eg. Silicon) ? B-physics
analyses
D0 efficiency -50 pb-1 ? B-physics analyses
Physics Results in this talk are from 70pb-1 _at_
CDF and 50pb-1 _at_ D0
5
Why Beauty at the Tevatron ?
s(bb) at ?(4S) 1nb (B-factories) s(bb) at Z0
7nb (LEP) s(bb) at pp (1.96TeV/c2)150mb
(Tevatron Experiments) More B _at_ Tevatron but
inelastic s at tevatron is 103 x s(bb) -Must
select b-data online, key appropriate detector
triggers -Rewards can produce all B-hadrons eg
B?, B0, Bs, Bc ?, ?b etc (unlike B-factories)
higher s than at Z0 Signatures for B Selection
use at CDF D0 -High PT leptons from b ?
mnX or b ? enX (CDF D0) -Di-leptons from B ?
J/yX, J/y ? mm- (CDF D0) -Utilize long B and
charm lifetimes ? large impact parameter (IP)
of daughter tracks (CDF, D0 in progress)

6
The CDF D0 Detectors in Run-II
New Time of Flight (TOF) some hadron ID New
Silicon (SVT) online Si tracker Select high IP
tracks from b and c _at_ trigger level (First time
at a hadron collider !) Improvements over
Run-I -Silicon Detector 3-D tracking, 5 layers
B vertex, track IP resolution, -Faster Drift
Chamber Momentum measurement -Greater muon
coverage Select b, c ? m
CDF Detector
New 2T Super conducting Magnet New Silicon
tracker (vertex, track IP resolution) New Fiber
tracker Momentum New Si Track Trigger
(displaced vertices) (Coming soon) Improvements
over Run-I -Calorimetry and faster
readout -Upgraded muon system.
D0 Detector
D0 has a magnetic field, and is able to pursue a
competitive B-physics program as well !
7
Data Samples The J/y ? mm- at CDF and D0
(Run-II)
75K at D0, completely new capability ! (40 pb-1)
0.5M at CDF (70 pb-1)
Two Fully Reconstructed B-hadron ? J/y states at
CDF D0
B ? J/y KS CDF220, D045 (Run-II) (D0 had none
in Run-I)
LB ? J/yL CDF53, D016 (Run-II)
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Data Samples B and Charm Using the high Impact
Parameter (IP) (Hadronic) trigger
Select events by requiring -2 tracks with
IPgt100 mm - track PT gt 2GeV/c - sum 2-track
PT gt 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/y trigger
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Data Samples B()?luD decays using hybrid
trigger
One lepton (PTgt3 GeV/c) one high IP
(gt120mm)track -High IP track means we can go
lower in lepton PT -Statistics much higher than
Run-I (lower PT thresholds) (x4-5 increase in
statistics) Used for 1) High statistics
lifetime and mixing analyses 2) calibration
samples for tagging (B ? lnD)
Drawback worse vertex resolution due to missed
neutrino Some numbers BglD0X (D0gKp) 10000
events, BglDX (DgKpp) 5,000 events also Bs
decays (later)
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Physics Results lifetime, mass, from fully
reconstructed B?J/y X modes Standard Technique
Data from J/y?mm- di-muon trigger -
Reconstruct vertex - Calculate decay proper
time, mass errors - Fitting for Massfit mass
only - Fitting for LifetimeFit mass and lifetime
distributions in single step


Probability Density Function and normalization
An Example B ? J/y K at CDF
Technique applied to several decays B gJ/y K,
B0 gJ/y K0 (K0 g Kp), Bs g J/y f (f gKK)
LbgJ/yL (Lgpp)
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Physics Results Bs ?J/y f, Lifetime and Mass
J/y ? mm- and f ? KK- (using di-muon (J/y)
trigger) 1) Run-I we had 60 at CDF. 2)
Run-II we have 136 at D0 and CDF Worlds
largest sample of fully reconstructed Bs decays
remains at the Tevatron
CDF M(Bs) 5365.5 ? 1.29(stat)?0.94 (sys)
MeV/c2, D0 M(Bs) 5360 ? 5CDF t(Bs) 1.26 ?
0.2 (stat) ?0.02(sys) ps, D0 lifetime analysis in
progress
Fit has one lifetime (width) but this mode
contains two lifetimes CP even and CP odd
Bs With higher statistics we can use angular
variables disentangle CP states fit two
lifetimes (widths)
Why is the width difference interesting ? -Bs
width difference DGs predicted to be large 10
-SM DGsA.xs (xsBs mixing Parameter) -If xs
is large and DGs is small or vice-versa ? sign
of new physics -SM CP violation in Bs ? J/yf 3
if extra-SM CP violation phase Sin2e then DG
s,measured DG s,SM.Cos2e (DGs and CPV are
complementary)
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Physics Results LB, leptondisplaced track and
purely hadronic data samples (have shown J/y 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
Lifetime in hadronic, hadronlepton modes
require correction for IP cut bias missing ?
Expect results this summer
?b ? ?cp ? pK? p
Note on LB A search for CP violation in Baryon
decays is planned using LB ? pp
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Physics ResultsTesting HQE A summary of results
HQE Predicted B Lifetime hierarchy tBc ltlt tXb0
tLb lt tBd tBs lt t B- lt t Xb-

• CDF (70 pb-1) t(B ) 1.57?0.07?0.02 ps using
  (B ? J/yK)
• t(B0 )1.42 ?0.09?0.02 ps
  using (Bd ? J/yK0)
• t(B)/t(Bd)
  1.11 ? 0.09 (Run-II)
• t(Bs)/t(Bd) 0.89
  ?0.15 (Run-II)
• D0 (40 pb-1) t(B )1.76 ? 0.24 ps using
  (B?J/yK)

BELLE (PRL 88 171801 2002) using
Bd?D()-(p,r), J/yKS,J/yK0 and B?D0p,
J/yK t(B)/t(Bd) 1.0910.0230.014
BABAR fully reconstructed decays Bd ?
D()-(p,r,a1), J/yKS,J/yK0 and B ? D0p,
J/yK t(B)/t(Bd) 1.0820.0260.012 BABAR
partially reconstructed decays(B?D,D l
n) t(B)/t(Bd) 1.064 0.031 0.026
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Physics ResultsTesting HQE A summary of results
s(t(B)/t(Bd)) surpasses theory 1.067 ?0.027
(HQE) (_at_ both Tevatron and B-factories) s(t(Bs)/t
(Bd)) doesnt (yet) 0.998 ?0.015 (HQE)
Tevatron Projection s(t(Bs)/t(Bd) ) and
s(t(Bd)/t(Lb)) lt1 in Run-II ? important test for
HQE Current LB lifetime is below HQE prediction,
with LB ? J/yL can have unambiguous
determination
These results also give us confidence that
vertexing works very well this is a crucial
ingredient for Bs mixing and CP violation studies
(more later)
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Physics Results Charm physics at CDF Ds-D
mass difference
First Run-II publication from CDF-comparable with
recent results
1) Data Selected from the hadronic trigger 2)
Both Ds,D decay to fp with f?KK- 3)
Kinematics of both decays identical 4) Simply
measure difference

• Ds - D mass difference
• 2400 Ds and 1600 D in only
• 11.6 pb-1 of data
• ?m 99.28 0.43 0.27MeV/c2
• In agreement with old world average
• 99.2 0.5 MeV/c2 (PDG CLEO2, E691)
• and with recent BaBar result
• 98.4 0.1 (stat) 0.3 (syst) Mev/c2

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Physics Results Charm physics at CDF Search for
Flavour Changing Neutral Current decay D0?mm-
SM predicts a branching ratio (BR) of O(10-13)
for D0?mm-
Some R-parity violating SUSY models predict
branching ratios upto O(10-6)

• Technique
• D0?pp- BR is well known identical acceptance
• to D0 ?mm-
• 2) Use D0?D0p to tag D0 in D0?K-p (thus no K
  vs p ambiguity)
• 3) See how many ps fake ms per PT
• 5) Look for D0 ?mm- in same sample
• 6) Subtract D0?pp- faking D0?mm-
• 0 events found in 2s search
• window

CDF Result BR(D0?mm) lt 2.4x10-6 better than
most recent world average ( PDG 90CL lt 4.1 x
10-6 )
A similar analysis of the rare decay Bs ? mm-
establishes a 4s sensitivity to signal for
branching ratios gt3.3x10-6
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Physics Results Charm physics at CDF Search for
CP violation (CPV) in Charm decays
1) c and u quarks dont couple to t ? box diagram
contributions are tiny 2) 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 fKK- and pp-

• Method Using data from Hadronic Trigger
• -Collect D?D0p sign of p tags flavour of D
• -Search for D0? KK-, D0? pp-, D0 ? pp- D0?
  KK-
• Correct for tracking efficiency for vs - p from
  D?D0p
• -Count number of decays in each mode after
  corrections

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Physics Results Charm physics at CDF Search for
CP violation in Charm decays
Cross-check Measure Ratio of Branching Ratios
_at_CDF G(D0? pp-)/G(D0? Kp-)9.380.180.10
G(D0? KK-)/G(D0? Kp-)3.686 0.076
0.036 FOCUS G(D0? pp-)/G(D0?
Kp-)9.930.140.14 G(D0? KK-)/G(D0?
Kp-)3.530.120.06 CDF accuracy is comparable
and consistent with FOCUS (2003) and World
average 2.880.15 (PDG)
93560 D?D0p with D0?Kp-
3697 D?D0p, D0? pp-
8320 D?D0p, D0? KK-
CLEO Result (2001)
First attempt at measuring CPV at CDF in Run-II
ACP(D0? (pp-)) 0.02.20.8 ACP(D0? (KK-))
1.9 3.20.8
ACP(D0? (pp-))2.01.70.6 (PDG
0.51.6) ACP(D0? (KK-))3.01.90.6(PDG
2.12.6)
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Mixing and CP violation (CPV) in B decays
Key Issues Tagging Flavour Correctly
... being able to tag at all
Statistical power eD2 ? N events count for eD2N
pure events
Same side tagging
Opposite side tagging
Concept Look for charged tracks around
reconstructed B of interest, Higher e Look for
m,e from B decay Look for p (K) from
hadronization of B (Bs)
ConceptLook for B on opposite side of B of
interest -Look for m,e -Look for p or K -Use
weighted jet-charge Disadvantages Opposite B
not in acceptance (60) or mixes (B0)
Sharpen algorithms on B decays (where b-flavour
is known eg B ? J/yK )
CDF ?D2 working on using TOF to do Kaon
tagging first mixing analyses to quote a final
number D0 ?D2 3.1 Jet Charge, ?D2 4.7
Lepton
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Mixing and CP violation (CPV) at Hadron
colliders
Run-I, CDF were able to do 2s measurement of
sin2b competitive xd (Dmd/G) measurements can
do tagging in hadron collider environment
Sin2b0.790.39(stat)0.16(sys) (CDF
1996) Sin2b0.76 0.067(stat)0.034(sys) (BaBar
2002) Sin2b0.7190.07(stat)0.035(sys) (Belle
2002)
CDF In Run-II with 40-50 x more Bd ? J/yKS
decays can get d(sin2b)0.05 D0 Similar
statistics Cant be competitive with BaBar and
BELLE Redo the measurement because -Its an
important benchmark -Gives credence to other CPV
measurements eg. in B ? hh- Bs ? J/yf
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Physics Prospects Toward Bs mixing at CDF
fully reconstructed decays
Decays we plan to use B0s? Ds???, B0s?
Ds??????? Proper time resolution ?t 45 fs ? t
? ?PT/PT
First observation of mode Bs?Dsp-with (Ds ?fp,
f ?KK-) !
-Need to tag initial B flavour -projection awaits
final eD2
Plan to increase statistics from . More
efficient online SVT (Silicon Tracker) utilizing
any 4/5 Si layers . Dynamic pre-scaling of
trigger at Level2 (hadronic trigger) (x2-4) .
Reconstruct with more Ds decays eg K0K?, ?????

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Aside Physics Results Ratio of branching
ratiosof Bs?Ds p to Bd?D p
Interest in Bs ? Ds p is mostly due to Bs
mixing butweve also measured the ratio of
branching ratios G(Bs ? Ds p)/G(Bd ? Dp )
Normalization mode is Bd ? D p , D ? K
pp- Kinematically Bs ? Ds p, Ds ? fp ,
f ? KK-
Using -numbers of Bs and Bd in our
signals -efficiencies from Monte-Carlo -D , Ds
BR are from PDG, obtain
Using fs/fd 0.2730.034 from PDG obtain
were beginning to fill in PDG section on the Bs
23
Physics prospectsBack to Bs mixing at CDF
partially reconstructed decays
Use new hybrid displaced tracksingle lepton
trigger
Decays included
Accounting for missed neutrino Bs ? Ds?l, Ds?l
(Ds?????, K0K?, ?????) expect 40K events in 2
fb-1 st is worse due to missed u (K factor) ?t
60 fs ? t ? ?K/K, ?K/K 14 If one Bs lifetime
is fit in any flavour specific mode tfit
(tBsCP2tBsCP-2)/(tBsCPtBsCP-) from which DGs
can be determined as well
24
Physics Prospects CP violation in B?hh- decays
determining angle g (CDF), Method
Five observables,
Tree and penguin graphs for B?pp- Bs?KK-
Tree gt penguin in B?pp- vice-versa in Bs?KK-
-CP Asymmetry in B?pp- Sin2(gb) (without
penguin) -CP Asymmetry in Bs?KK- Sin2g
(without penguin) -Assume SU(3) symmetry
replace s-d Hadronic matrix element ratios
penguin/tree same for both modes
Four unknowns dratio of penguin/tree hadronic
matrix elements q phase of d g,b weak phases
Constrain Sin2b from B-factories, CDF/D0
results and measure g
Proposed by R.Fleischer, PLB459 1999 306
25
Physics Prospects CP violation in B?hh- decays
determining angle g (CDF)
Monte-Carlo plot below shows Bd ? pp-,Bs ?
KK- Bs ? K p, Bd ? K p (From
Monte-Carlo)-all pile up in the same region
B ? hh- from hadronic trigger Includes
B?pp-,Bs?KK- Bs?K p, and Bd? K p
Must disentangle contributions from each mode to
signal To do this we (will) use -dE/dx based K
and p identification -Kinematical variable
separation M?? vs a(1-p1/p2)?q1 -Width of
signal -Frequency of oscillation in CP asymmetry
26
Physics Prospects CP violation in B?hh- angle
g (CDF)
dE/dx calibration using D ? D0p?, D0 ?Kp (p
from D unambiguously distinguishes K, p from
D0)
Mpp vs a for each B?hh- mode
Sanity check Measure Ratio of Branching
Ratios CDF G(Bd ? pp-)/G(Bd? Kp-) 0.26
0.110.055, PDG
Method works ! Confirmed by Sanity check
against ratio of branching ratios Have first
observation of Bs ? KK- Its a CP Eigenstate Can
use this To measure DGs as well !!
Yield for each mode Bd ? pp- 148?17 Bd ? K
p 39?14 Bs ? K p 3?11 Bs ? KK-
90?17 First observation !
Back to projection of g measurement Expected
(2fb-1) accuracy ?(?) 10?(stat) 3?(syst)
(syst SU(3) breaking)
27
Conclusions

• CDF D0 are in the first phase (lt200pb-1) of
  data taking expect to
• a) Test HQE especially with LB and Bs
• b) Search for CPV and FCNC in Charm B rare
  decays
• c) Establish tagging and lifetime measurement
  techniques with new data
• 2) Next phase (gt200pb-1 lt500pb-1) will
• a) set limits on (or measure) Bs mixing
• b) search for CPV in the neutral B system
• 3) Final Phase (end Run-IIa) (gt500pb-1 and
  lt2fb-1) measure
• a) Bs width difference DGs mixing
  parameter xs
• c) CKM angle g
• d) search for CPV in LB ? pp
• e) and search for unexpectedly large CPV in Bs
  ? J/yf
• Pursue in the first phases a program partially in
  parallel to and in the last phase complementary
  to the B-factories

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Backup Slides
29
Aside Physics Results Ratio of branching
ratiosof Bs?Ds?p? to Bd?D?p?
Interest in Bs?Ds?p? is mostly due to Bs mixing
butweve also measured the ratio of branching
ratios G(Bs?Ds?p?)/G(Bd?D?p?)
Normalization mode is Bd ? D?p?, D? ?
K?pp- Kinematically Bs?Ds?p?, Ds? ? fp?, f ?
KK-
Ratio of Bs to Bd signals is
Where e are determined from Monte-Carlo D?, Ds?
BR are from PDG, obtain
Using fs/fd 0.2730.034 from PDG obtain
were beginning to fill in PDG section on the Bs
30
Physics Results Average B-hadron lifetime from
partially reconstructed B?J/yX decays.
This is a sanity check of our B?J/y sample
Obtain Average B hadron tB From all B ? J/y
(other stuff) decays B is not fully
reconstructed
If Fully reconstructed B -ct c.(time in B rest
frame) -Lxy 2-d decay length -MB mass -PT
transverse momentum
D0 Inclusive B Lifetime
If Partially reconstructed B -Correct for missed
daughters F(PT) (from by Monte-Carlo) -tB
is an estimate -it is the average lifetime of
all hadrons decaying to J/y
Results from D0 and CDF tB1.561?0.024?0.074 ps
D0 (40 pb-1) tB1.526?0.034?0.035 ps CDF (18
pb-1) Both consistent with PDG tB 1.564 ?
0.014
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CDF Integrated Luminosity
Data used for Todays results Mar 02 Jan 03
130 pb-1 (delivered) 100 pb-1 (to tape)
B/Charm 70 pb-1
commissioning
32
Physics Prospects Bs width difference using Bs?
J/y f

• One lifetime(width) has been fit in this mode
• But contains two distinct lifetimes CP CP-
  Bs, significant lifetime (width) difference
• DGs1/tB1-1/tB2
• 2) Extract DGs fit two lifetimes, use single
  angle to separate CP and CP- Bs (Transversity
  angle q)
• SM prediction for DGs 0.10Gs also DGs A.xs
  (xs Bs mixing parameter) if DGs is small and xs
  is large or vice-versa Sign of new physics
• CDF prediction for 2fb-1 d(DGs)0.05

Two CP states transversity
Two CP states lifetime
Total function and normalization
Current limit (LEP) ??s / ?s lt0.31, from
branching ratio of Bs?Ds()Ds?()
Note SM CP violation in this mode O(3), if
large ?new physics CP asymmetry sin2e ? DGs,
measured DGs,SM.Cos2e (complementary)
33
Physics Results lifetime, mass, from fully
reconstructed B? J/y X modes Standard Technique
Data from J/y?mm- di-muon trigger 1)
Reconstruct vertex according to decay topology 2)
Calculate decay proper time mass errors 3) If
fitting for massfit mass only 4) If fitting for
lifetimeFit mass and lifetime using bi-variate
Probability density function (PDF) in likelihood
Probability Density Function (pdf)
1) Signal Lifetime


2) Signal Mass
An Example B -gtJ/y K at CDF
3) Signal for Mass only analyses
4) Signal pdf in mass and lifetime
5) Signal for lifetime analysis
Both the mass and lifetime distributions are fit
in a single step. Technique is applied to B
gJ/y K, B0 gJ/y K0 (K0 g Kp), Bs g J/y f (f
gKK), LbgJ/yL (Lgpp)
6) Normalization mass and lifetime
34
B physics prospects(with 2fb-1)
Both competitive and complementary to B
-factories

• Bs mixing Bs ?Dsp(Ds3p) (xs up to 60, with xd
  meas. one side of U.T.)
• Angle ? B0? J/? Ks (refine Run1 meas. up
  to ?(sen2?) ? 0.05)
• CP violation, angle ? B0? pp(pK), Bs ? KK(Kp)
  
• Angle ?s and ??s/ ?s Bs? J/? ? (probe for
  New Physics)
• Precise Lifetimes, Masses, BR for all B-hadrons
  Bs, Bc, ?b
• (CDF observed Bc ? J/? 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 !!

35
Sin(2?) in B0?J/y Ks
?ms/?md
a
g
b
N(B0)(t) - N(B0)(t)
ACP(t)
D?sin(2b)?sin(Dmd t)
N(B0)(t) N(B0)(t)
In Run1 measured
B0 ? J/? Ks J/? ? ??
sin(2b)0.790.390.16
(400 events)
sin(2b)0.910.320.18
(60 B0 ? ? (2S) Ks)
With 2fb-1 can refine this measurement Although
no way to compete with B-Factories !

• 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/? ? ee? 10,000

Stat. Error
Expect s(sin2b) ? 0.05
Systematic 0.5xStatistical (scales with control
sample statistics)
Combined eD2 from 6.3 to 9.1 (Kaon b-tag)
Same S/B 1
36
Tevatron Performance
3.8 x 1031

• 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 values
• additional improvements (10-20) expected
  from Jan. 3weeks shutdown

Initial Luminosity
July 01
Now

• CDF operations
• Commissioning Summer 2001
• Physics data since February 2002
• Running with gt90 Silicon integrated
• since July 2002

On-tape Luminosity
110 pb -1

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

July 02
Feb 02
37
Quadrant of CDF II Tracker
TOF 100ps resolution, 2 sigma K/? separation for
tracks below 1.6 GeV/c (significant improvement
of Bs flavor tag effectiveness)
TIME OF FLIGHT

• COT large radius (1.4 m) Drift C.
• 96 layers, 100ns drift time
• Precise PT above 400 MeV/c
• Precise 3D tracking in ?lt1
• ?(1/PT) 0.1GeV 1 ?(hit)150?m
• dE/dx info provides 1 sigma K/? separation above
  2 GeV

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

LAYER 00 1 layer of radiation-hard silicon at
very small radius (1.5 cm)
(achievable 45 fs proper time resolution in Bs ?
Ds p )
38
CDF II Trigger System
3 levels 5 MHz (pp rate) ? 50 Hz (disk/tape
storage rate) almost no dead
time (lt 10)

• XFT EXtremely Fast Tracker
• 2D COT track reconstruction at Level 1
• PT res. DpT/p2T 2 (GeV-1)
• azimuthal angle res. Df 8 mrad
• SVT Silicon Vertex Tracker
• precise 2D SiliconXFT tracking at Level 2
• impact parameter res. ?d 35 ?m
• Offline accuracy !!

CAL
MUON
CES
COT
SVX
XFT
XCES
Matched to L1 ele. and muons
XTRP
enhanced J/? samples
L1 CAL
L1 MUON
L1 TRACK
GLOBAL L1
SVT
L2 CAL
CDF II can trigger on secondary vertices !!
Select large B,D samples !!
GLOBAL LEVEL 2
TSI/CLK
39
SVT Triggering on impact parameters
150 VME boards

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

40
B triggers conventional
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

Suffer of low BR and not fully rec. final state
Nevertheless, many important measurements by CDF
1 B0d mixing, sin(2?), B lifetimes, Bc
observation,

• Now enhanced, thanks to XFT (precise tracking at
  L1)
• Reduced (2?1.5 GeV/c) and more effective PT
  thresholds
• Increased muon and electron coverage
• Also J/? ? ee

41
XFT performance
Efficiency curve XFT threshold at PT1.5
GeV/c ? 96.1 0.1 (L1 trigger)
Offline track
XFT track
11 pb-1

• XFT L1 trigger on tracks
• better than design resolution
• ?pT/p2T 1.65 (GeV-1)
• ?? 5.1 mrad

53.000 J/? ? ??
42
SVT performance

• I.P. resolution as planned
• ?d 48 ?m 35 ?m ? 33 ?m

intrinsic
D0 ? Kp used as online monitor of the hadronic
SVT triggers
transverse beam size

• Efficiency

S/B ? 1
90
soon
80
43
TOF performance

• TOF resolution (110ps) within 10 of design value

Background reduction in ? ?KK Low PT (lt 1.5
GeV/c) track pairs before and after a cut on TOF
kaon probability x20 bkg reduction, 80 signal
efficiency
with TOF PID
S/N 1/2.5
S/N 1/40
44
CDF J/y cross section
0ltptlt0.25 GeV
5.0ltptlt5.5 GeV
10.0ltptlt12.0 GeV
s(ppgJ/y pTgt0 hlt0.6) 240 ? 1 (stat)
?35/28(syst) nb
45
Lots of charm from hadronic triggers
With 10 pb-1 of hadronic trigger data
Relative Br. Fractions of Cabibbo suppressed D0
decays
Already competitive with CLEO2 results (10fb-1 _at_
?(4S)) !!!!!
?(D?KK)/?(D?K?) 11.17 ? 0.48(stat) ?
0.98 (syst) ?(D?? ? )/?(D?K?) 3.37 ?
0.20(stat) ? 0.16(syst)
O(107) fully reconstructed decays in 2fb-1

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

46
Data Samples B and Charm from the hadronic
trigger
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/y trigger
Some charm is prompt
D from direct charm Points back to beam spot
..Some charm is from B
D from B has a impact Parameter wrt beam spot
An example of B reconstructed Using data from
this trigger
..to separate prompt Ds from Ds coming from B
Prompt Charm D0?K?
86.5 ? 0.4 (stat) D??D0 87.6 ?
1.1 (stat) D??K?? 89.1 ? 0.4
(stat) Ds??? 72.4 ? 3.4 (stat)
We have B and tons of Charm as well !
47
B0s mixing expectations with 2fb-1
xs ?ms??(B0s)
Bs ? Ds?, Ds ? ? ? Ds ? ??, KK, ???

• Signal 20K (fp only) - 75K (all) events
• with SVT hadronic trigger
• BR (Ds ?) 0.3 BR (Ds ? ? ?) 0.8
• Resolution
• ?(c?) 45 fs (with Layer00)
• eD2 11.3 (with TOF)
• S/B 0.5-2 (based on CDF I data)

S.M. allowed range 20. lt Xs lt 35.
5s sensitivity up to Xs 63 (S/B 2/1) Xs
53 (S/B 1/2)
Can do a precise measurement or evidence for
new physics !
48
Physics Results Average B-hadron lifetime from
partially reconstructed B?J/yX decays.
This is a sanity check of our B ? J/y sample
Obtain Average B hadron tB From all B ? J/y
(other stuff) decays B is not fully
reconstructed
D0 Inclusive B Lifetime
Partially reconstructed B -Correct for missed
daughters F(PT) (from by Monte-Carlo) -tB
is an estimate -it is the average lifetime of
all hadrons decaying to J/y
Results from D0 and CDF tB1.561?0.024?0.074 ps
D0 (40 pb-1) tB1.526?0.034?0.035 ps CDF (18
pb-1) Both consistent with PDG tB 1.564 ?
0.014