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					 CDF Status and Prospects for
           Run 2




Tara Shears
                  Introduction
Accelerator / detector overview:
   • Tevatron overview
   • CDF overview
   • Luminosity

Physics prospects and first results:
   • QCD, Heavy flavour, Electroweak, Searches

Conclusions
Tevatron overview
                      The Tevatron

CDF:                                          D0:
706                                           650 people
people                                        18 countries
12
countries




              _
            p-p collisions at s = 1.96 TeV
   Tevatron operating parameters

              Run 1               Run 2               Now

Date          1992 – 1996         2001 - 2009         2003

Integrated    110 pb-1            5.0 – 9.5 fb-1      160 pb-1
Luminosity
c.m. energy   1.8 TeV             1.96 TeV            1.96 TeV

Luminosity    2 x 1031 cm-2 s-1   2 x 1032 cm-1 s-1   4.8 x 1031 cm-2 s-1


Bunch         3.5 ms              396 – 132 ns        396 ns
spacing
CDF
  CDF




XFT,SVT triggers
               Silicon system
• 3 separate detectors:
   – L00 (radius 1.5-2 cm)
   – SVX (radius 2.5-
     10.5cm)
   – ISL (radius 20–30 cm)
   – Covers +- 50 cm in z
   – ~750 000 channels!
• Installed in March 01
Si performance

                 % silicon ladders integrated

                 % good silicon ladders

                 % bad silicon ladders

                 % average error




            ~ 90% good
            and operational
          SVT Level 2 Trigger
Level 2 hadronic B
  trigger
   s(d0) ~ 48 mm
   15 ms operation
• online primary vertex
  finding, tracking
• trigger on displaced
  tracks
                                M(hh)
             TOF Performance

TOF resolution within 10 –
  20% of design value
  (100 ps)
Calibration ongoing


                 eg. f
                               S/N = 1942/4517


    S/N = 2354/93113     TOF
Luminosity
               Integrated luminosity

                                               Total lumi (pb-1)




        Run 1 lumi




Mar. 2001            50-80pb-1 will be shown        May. 2003
Physics in Run 2
                Physics in Run 2
                                          # events in
                Jet cross-section,        1 fb-1
QCD
                shapes, multijet events       1014

Heavy flavour   Lifetimes, cross-
                section, Bc, LB, Bs           1011
                studies, CP violation,
                xs
                                              107
Electroweak     W: mass, width, gauge
                couplings
                Top: mass, cross-
                                              104
                section, branching
                ratios

Searches        Higgs
                SUSY, compositeness,
                leptoquarks etc.
                                    QCD
    Vital to understand QCD in order to perform precision/search physics

Run 1 inclusive jet cross section




Consistent over 7 orders of magnitude   BUT    deviation at high Et
                      SM explanation
                                       Run 2 - more high Et jets:
                                       Test QCD at high Et
                                       Discriminate between new physics
                                       and gluon PDF




                                                             New bins for
                                                             Run 2
    Important gluon-gluon and
gluon-quark contributions at high Et
Gluon PDF @ high x not well known.
                               Dijet mass
       Jet 2                 Jet 1
ET = 546 GeV (raw)    ET = 583 GeV (raw)    Highest Et jets seen
 hdet = -0.30         hdet = 0.31           at the Tevatron!


                                    Had E
                                    Em E



                                                          Consistent
                                                          with SM

h-f view
      CDF Run II Preliminary
           M(jj)=1364 GeV/c2
                 Heavy flavour

Run 2 improvements:          Measurements in Run 2:
  Better tracking systems      Bs mass, lifetime, mixing
  TOF for K-p separation       CP from Bs, B0
  Displaced track triggers     B baryon lifetime, mass
  Increased lumi for rare      Rare decays, Bc study
    decays




          Tevatron only place to study Bs, b
                    baryons, Bc
            Heavy flavour using J/y


Inclusive B lifetime:
Tracking + alignment proof
<tb>=1.526  0.034  0.035 ps (CDF)

(PDG 02: 1.564  0.014 ps)
              Heavy flavour using J/y
                                            LBJ/yL
Exclusive B reconstruction:
t(Bs)=1.26  0.2  0.02 ps
(PDG 02: 1.46  0.057 ps)
m(Bs)=5360.3  3.8 +2.1-2.9 MeV
(PDG 02: 5369.6  2.4 MeV)


                                  BsJ/yf
   Heavy flavour using SVT+TOF
Allows exclusive hadronic
decay mode reconstruction:
                           Bs mixing
  x = Dm/G
                      width
Oscillation freq.


Currently: xs > 14.6
Projection for 15 fb-1:
    – 20 000 Bs decays
    – Effective tagging eff. *2                      e-t/t
       cf. Run 1
    – Sensitive to xs < 63


                                  Pmix(t) = 0.5*(1-cos(Dm t))
                          Bs mixing
•    Dm  DG = f (tH, tL )            complementary method
    – Separate eigenstates and
      measure each lifetime

1) BS  DS+ DS- (CP even)
   Work continuing in
   triggering on these difficult
   hadronic modes
   (track/vertex/reconstuct)
2) BS  J/y f (CP
   even&odd) Different
   angular distribution for mm
   allow separation of CP even
   and odd states
3) BS  J/y h (CP odd)
Bs mixing reach

          Not much lumi needed for
          quick limit BUT:
          Need had. B trigger
          Need tracking at full spec.
          Need tagging understood
          => Results summer 2004?
            Charm: M(Ds              +)-m(D+)

                                                   Submitted to PRD!

Cross-check of lattice QCD,
HQET charm mass
Use large SVT triggered
charm sample




                              m(D+s)-m(D+) = 99.41  0.38  0.21 MeV/c2
                              PDG 02: 99.2  0.5 MeV/c2
Electroweak physics
             Electroweak:W,Z

                             Measurements in 2fb-1:
Run 2 benefits:
                             m(W) measured to 40 MeV
s(W), s(Z)  12 %              (sys. dominated - theory)
                             G(W) measured to 30 MeV
s(WW), s(ZZ)  13 - 22%
                             couplings measured to ~0.3




    W,Z essential calibration signals for high Et
                       physics
     Electroweak: W candidates
                   W->mn                        W->en




21599 candidates in 72 pb-1   38628 candidates in 72 pb-1
     Electroweak: Z candidates
                       Z->ee                     Z->mm




1830 candidates in 72 pb-1     1631 candidates in 72 pb-1
                     Electroweak: top
Run 2 benefits:
   s(tt)  40%                                                  l q q
   More luminosity
                                                                n q q
   Increased b tagging
     efficiency + lepton
                                                            l l q
     acceptance
Measurements in 2 fb-1:                                         n n q
   m(top) ~ 1.2% (cf. 2.9%)        12%
   s(tt) ~ 10% (cf. 25%)
                                            44%
   s(single top) ~ 20% (1st!)                            44 %
   |Vtb| ~ 12% (1st!)


    Tevatron only place to study top until LHC startup
First dilepton tt candidate
                         Top Results
                                        M(top) (run1) = 176.1 ± 6.6 GeV/c2
s(tt)      PRELIMINARY

            D0 l+jets
           CDF l+jets

                           D0 l+l


               CDF l+l


        NLO: 6.7+0.71-0.88 pb
        (mt=175)




                                    M(top) = 171.2  13.4stat  9.9sys GeV/c2
            Top mass motivation




Run 2
expected
precision
         Electroweak: single top
•  s(t) ~ 0.9 pb (W*)
•  s(t) ~ 2.4 pb (Wg)
•  s(t) |Vtb|2
• Tag by 1 high Pt e,m
                     /
  + 2 jets ( 1 b) + Et
• Signal = peak in Wb
  invariant mass plot
Searches
    Production and Decay of Higgs




  2 fb-1 data: ~ 2,000 Higgs
(200 in association with W,Z)
Backgrounds much larger than
          at LEP
                        Higgs: rates
channel   rate   mH= mH= mH=
                 110 120 130

lvbb      s      4.8   4.4   3.7
          b      19    26    46
nnbb      s      4.6   3.2   2.1
          b      36    39    30
llbb      s      0.9   0.6   0.4
          b      3.2   23    1.9
qqbb      s      3.5  2.5  1.3
          b      2800 2300 2000
               Expected Luminosity in Run 2


           Expected Luminosity in Run 2 (updated)




                 Exclude m(H) ~130 GeV
     Discover m(H) ~120 GeV, exclude m(H) ~ 190 GeV

Note: all numbers under review (new estimates for summer)
                      SUSY: stop
stop decays:
       ~    ~
(eg.) t b c1+
            ~+
            c1  l n ~ 0
                     c
     ~
 (or) t  b W ~ 0
              c
            Wln
tag with b jet + lepton
+ Etmiss
         SUSY: trilepton topology


Study lepton spectra for        Specific search for decays
                                            ~
                                    ~ +  c0 l n
                                    c1
sensitivity to different SUSY                  1
                                    ~0     ~
models                              c 2  c 01 l l
    ~ ~
eg. c+1 + c02 are produced,     3 leptons, often enriched in
  ~0
   c 1 is LSP                      taus
               SUSY: trilepton spectra

Run 2
exclusion
limits for 2
models:
                               /
                     SUSY: eeggEt

     /
eeggEt event in Run 1:
radiative decay of
neutralino to gravitino?
(gravitino lsp)
 _
       ~ ~
pp  ci +cj-
       ~0 ~ 0
   c 1c 1+X
           ~~
   ggGG+X
Look for more events, +
gg channel in Run 2
             Searches: diphoton
Diphoton:
  GMSB: radiative decay
     to LSP (gravitino)
  If neutralino NLSP:



                /

               ggEt

                          MC > 113 GeV/c2 @ 95%
                            C.L.
             SUSY: projected limits
Expected
limits for
Run 2:




(taken from Savoy-Navarra, EPS 99)
Conclusions
                  Conclusions
Run 2 has just started at the Tevatron
   – New c.m. energy, high luminosity, new detectors
Exciting program of physics ahead
   – Tevatron only place where top can be studied
   – Possibility of Higgs + new physics
   – Many areas of electroweak, heavy flavour and QCD
     physics to explore
Run 2 physics underway … watch this space!!
Backup slides
            Jet Cross Section vs h




•QCD sub-processes at small angles
•Central jets are more likely to signal new physics (hep-ph
0303013)
               Peak fill luminosity

peak
                            Run II
lumi




       03/01                          05/03
   Tevatron Operations




Many reasons for not reaching design lumi
              Electroweak: m(W) errors
Error                     Run1b    Run 1b 2 fb-1     2 fb-1
                                                              Run 1b=
                          Wen     Wmn Wen         Wmn
                                                              110 pb-1
statistical               65 MeV   100 MeV 14 MeV    20 MeV

lepton                75 MeV       85 MeV   20 MeV   15 MeV
energy/momentum scale
lepton                    25 MeV   20 MeV   8 MeV    6 MeV
energy/momentum
resolution
W production model        47 MeV   44 MeV   30 MeV   30 MeV

Fitting, selection etc.   5 MeV    31 MeV   14 MeV   16 MeV

Total                     113 MeV 143 MeV 42 MeV     40 MeV
Heavy flavour physics
    Heavy flavour physics: lifetimes

 • First measurements
   which CDF will
   perform in b sector
 • Necessary step
                                 HQET:
   towards oscillation
                                 t(B+ )/ t (B0 )=1.05
 • Best measurement of
   Bs0, Lb. (Unique)             t( Bs0)/ t (B0 )=1.00
                                 t( Lb)/ t (B0 )=0.9 to 1.0
2 fb-1:
                                 Experiment:
3000 Bs => s(ct(Bs)) ~ 0.03 ps
                                 t( Lb)/ t (B0 ) is 0.78+-.04
2000 LB => s(ct(LB)) ~ 0.04 ps
Heavy flavour physics: lifetimes
    Heavy flavour physics: lifetimes
Millions of B mesons have already been produced in RunII.          XFT,SVT
Need to trigger and identify relevant decays. Leptons ‘easy’; hadrons difficult




                                                                        ~ 46%




                                         ct=458±10±11 mm (469±4 mm)
Look for J/y  mm
                              Next step: Bs, LB lifetimes…
     Exclusive lifetimes

Bs                  B0




B+                                   t(B+)




             ct=446 ±43stat. ±13syst. mm (502 ± 5)
                           Higgs
Look in diffractive mode pp  pHp
Reconstuct from missing mass of pp
system




                               CDF
                  55m



     25-30 GeV mass resolution standard method,
     ~ 0.5 GeV resolution diffractive mode
             Higgs


s small @
Tevatron,            Signal
                     (Cudell,
reasonable           Hernandez)
at LHC
                     Background

				
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