CDF Status and Prospects for Run 2
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Transcript of CDF Status and Prospects for Run 2
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
p-p collisions at s = 1.96 TeV_
CDF:
706 people
12 countries
D0:
650 people
18 countries
Tevatron operating parameters
Run 1 Run 2 Now
Date 1992 – 1996 2001 - 2009 2003
Integrated Luminosity
110 pb-1 4.4 – 8.6 fb-1 240 pb
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 5.2 x 1031 cm-2 s-1
Bunch spacing
3.5 s 396 – 132 ns 396 ns
CDF
CDF
XFT,SVT triggers
L00
SVX
ISL
Si performance
% silicon ladders integrated
% bad silicon ladders
% good silicon ladders
% average error
> 90% operational
L00 performance
L00 improves uniformity of impact parameter res.
d0
pT
SVT Level 2 Trigger
Level 2 hadronic B trigger(d0) ~ 48 m
15 s 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
TOFS/N = 2354/93113
S/N = 1942/4517
eg.
Luminosity
Integrated luminosity
Total lumi (pb-1)
Sep. 2003Mar. 2001
Run 1 lumi
Up to 180 pb-1 will be shown
Physics in Run 2
Physics in Run 2
QCD Jet cross-section, shapes multijet events
Heavy flavour Lifetimes, cross-section, Bc, B, Bs studies, CP violation, xs
Electroweak W: mass, width, gauge couplings
Top: mass, cross-section, branching ratios
Searches Higgs
SUSY, compositeness, leptoquarks etc.
# events in 1 fb-1
1014
1011
104
107
Consistent over 7 orders of magnitude deviation at high Et
QCDVital to understand QCD in order to perform precision/search physics
BUT
Run 1 inclusive jet cross section
SM explanation
Important gluon-gluon and gluon-quark contributions at high EtGluon PDF @ high x not well known.
Run 2 - more high Et jets:
Test QCD at high Et
Discriminate between new physics and gluon PDF
New bins for Run 2
Dijet mass
Jet 2ET = 546 GeV (raw)
det = -0.30
CDF Run II Preliminary
Jet 1ET = 583 GeV (raw)
det = 0.31
- view
Had E
Em E
Highest Et jets seen
at the Tevatron!
M(jj)=1364 GeV/c2
Consistent with SM
Nason, Cacciari
UPRF-2002-4
CDF Preliminary:(D*)
Cacciari: hep-ph/9702389
(B+): Phys Rev D65 052005
B
C
Discrepancy from Run 1:
(data)/(improved theory) ~ 1.7
C: similar effects seen
Aim: test predictions at Run 2
Heavy flavour production:
Run 1
Charm production: D0,D+,D*+,Ds+
Use SVT (5.8 pb-1) to obtain
D0 K-
D*+ D0
D+ K-
Ds+
Determine prompt component (fit D impact parameter)
Compare D to NLO
Combinatorics
Wrong K-
D0 i.p.
Charm production: D0,D+,D*+,Ds+
(D0, pT 5.5 GeV) = 13.3±0.2±1.5µb
(D*+, pT 6.0GeV) = 5.2±0.1±0.8µb
(D+, pT 6.0 GeV) = 4.3±0.1±0.7µb
(Ds, pT 8.0 GeV) = 0.75±0.05±0.22µb
Nason & Cacciari hep-ph/0306212
Heavy flavour
Run 2 improvements:Better tracking systems
TOF for K- separation
Displaced track triggers
Increased lumi for rare decays
Tevatron only place to study Bs, b baryons, Bc
Measurements in Run 2:Production
Bs mass, lifetime, mixing
CP from Bs, B0
B baryon lifetime, mass
Rare decays, Bc study
B masses
M(B+) = 5279.32 ± 0.68 ± 0.94 GeV (5279.0 ± 0.5)
M(B0) = 5280.30 ± 0.92 ± 0.96 GeV (5279.4 ± 0.5)
M(Bs) = 5365.50 ± 1.29 ± 0.94 GeV (5369.7 ± 2.4)
M(B) = 5620.4 ± 1.6 ± 1.2 GeV (5624 ± 9)
PDG
Charm: M(Ds+)-m(D+)
Cross-check of lattice QCD, HQET charm mass
Use large SVT triggered charm sample
Submitted to PRD!
m(D+s)-m(D+) = 99.41 0.38 0.21
MeV/c2
PDG 02: 99.2 0.5 MeV/c2
B lifetimes
c(B+) = 1.63 ± 0.05 ± 0.04 ps (1.671 ± 0.018)
c(B0) = 1.51 ± 0.06 ± 0.02 ps (1.537 ± 0.015)
c(Bs) = 1.33 ± 0.14 ± 0.02 ps (1.461 ± 0.057)
c(B) = 1.25 ± 0.26 ± 0.10 ps (1.229 ± 0.080)
More stats with SVT s.l. decays…
Heavy flavour using SVT(+TOF)
Allows exclusive hadronic decay mode reconstruction:
Bs mixing
xs = m/ps@Bs oscillation much faster
than Bd because of coupling to top quark:
Re(Vts)0.040 >Re(Vtd)0.007
• Use SVT to trigger Bs
• Tag charge at production• Tag charge at decay• Measure lifetime
B0
b s
sW
t
W+
tbB0
Vtb~1 Re(Vts)0.04
Pmix(t) = 0.5*(1-cos(m t))
e-t/
Predicted ms reach
Current (future) performance:– No. events: 1600
(2000) /fb-1
D2 = 4 (5) % t = 67 (50) fs
Improvements:– More Bs channels– Better tracking,
tagging
Sensitivity:• Current performance:
ms=15 ps-1 / 500 pb-1
(2)
• Future performance: ms = 18 ps-1 / 1.7 fb-1
ms = 24 ps-1 / 3.2 fb-1
– (both 5)
• m fL– 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/(CP
even&odd) Different angular distribution for allow separation of CP even and odd states
3) BS J/(CP odd)
complementary method
Bs mixing
Electroweak physics
Electroweak:W,Z
Run 2 benefits:
(W), (Z) 12 %
(WW), (ZZ) 13 - 22%
W,Z essential calibration signals for high Et physics
Measurements in 2fb-1:
m(W) measured to 40 MeV (sys. dominated - theory)
(W) measured to 30 MeV
couplings measured to ~0.3
W,Z resultsW
Z ee
12%
l q q
44%44 %
l l q
Electroweak: topRun 2 benefits:
(tt) 40%
More luminosity
Increased b tagging efficiency + lepton acceptance
Tevatron only place to study top until LHC startup
Measurements in 2 fb-1:m(top) ~ 1.2% (cf. 2.9%)
(tt) ~ 10% (cf. 25%)
(single top) ~ 20% (1st!)
|Vtb| ~ 12% (1st!)
q
First dilepton tt candidate
Top Results
M(top) = 177.5 +12.7/-9.4M(top) = 177.5 +12.7/-9.4statstat 7.1 7.1syssys GeV/c GeV/c22
M(top) (run1) = 176.1 ± 6.6 GeV/c2
Top mass motivation
Run 2 expected precision
Electroweak: single top
(t) ~ 0.9 ±0.1 pb (W*) (t) ~ 2.0 ±0.2 pb (Wg)
(t) |Vtb|2
Tag by 1 high Pt e, + 2 jets ( 1 b) + Et
Expect 18.5 ± 2.9 events, see 19
/
t(combined)<17.5pb @95% C.L.
Searches
Production and Decay of Higgs
2 fb-1 data: ~ 2,000 Higgs (200 H+ W,Z)
Backgrounds much larger than at LEP
Discover at m(H) ~ 115 GeV Exclude m(H) ~130 GeV
LEP mH>114.4 GeV @95% CL
8.6 fb-1
4.4 fb-1
SUSY: stop
stop decays:
(eg.) t b 1
1
+ l 0
(or) t b W 0
W l
tag with b jet + lepton + Etmiss
~
~ ~
~
~
~
Stop results
Long lived stop analysis:
High pt track, large TOF deposit
Expect 2.9 0.7 ± 3.1 events
See 7 in data
M(stop) > 107 GeV
SUSY: eeEt
eeEt event in Run 1:
radiative decay of neutralino to gravitino? (gravitino lsp)
pp i +j
-
01 0
1 + X
G G + X
Look for more events, + channel in Run 2
/
~ ~
~ ~
~ ~
_
/
Searches: diphotonDiphoton:
GMSB: radiative decay to LSP (gravitino)
If neutralino NLSP:
/
MMC C > 113 GeV/c> 113 GeV/c22 @ 95% C.L. @ 95% C.L.
Et
SUSY: projected limits
Expected limits for Run 2:
(taken from Savoy-Navarra, EPS 99)
Conclusions
Conclusions
Run 2 has 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!!