1. News and Communications
M. Cobal, University of Udine
Summary of recent results from CDF and DO
Plans for the future
Requests from the Speaker Committe

2. Tevatron- Introduction
Luminosity goal:
fb-1 by FY 2009
Record: 6.8x1031cm-2s-1

3. Two detectors CDF underwent serious upgrades: D0: change of philosophy
New tracking system
COT, new silicon tracker (6-7 layers DS+1 SS)
New forward calorimetry
Tracking at trigger level
Tracks at L1
Displaced from
D0: change of philosophy
New tracking system
Based on a 2T solenoid
New 8 layers (fiber) tracker
Secondary vertices capability (SVX)
Improved muon coverage
New features at trigger level

4. Data taking…7x1031…
Accelerator delivers..
Detectors use:

5. Top s (ttbar and single top)
A summary:
Single top process would measure |Vtb|2 directly...
s <13.7 pb (combined)
s<8.5 pb (t-channel)

6. Top – Cross-section A number of channels explored by D0
Nice comparison with past and theory…

7. Top Cross-Section Look for top content in W+jets sample SLT kinematic
soft m tag
Svx tag
NN on kinematic variables

8. Top Cross Section
A summary:

9. Top Cross Section A number of channels explored by D0
Nice comparison with past and theory…

10. Cross Section: all the results
Combined value will be calculated soon

11. Top Quark Mass Recent Updates
Run II data, ~126 pb-1   mt=  8.4 (syst) GeV/c2
Run II data, ~102 pb-1 mt=  7.1 (syst) GeV/c2
Run I data (revisited), ~125 pb-1 mt  =  3.6  3.9(syst) GeV/c2
Run II data, ~126 pb-1   Lepton + Jets mt=  6.2 (syst) GeV/c Likelihood Method
Run II measurements will be more precise than Run I results soon
In the meantime Run I Tevatron average was re-done with D0’s new update

12. mHiggs < 251 GeV/c2 (95% CL)
Top Quark Mass
New Run I Combination
mHiggs  = –45 GeV/c2 Or
mHiggs  < 251 GeV/c2 (95% CL)

13. Top mass and Higgs: Where we are

14. M. Mangano, IFAE, Apr 2004

15. Look in:
Paper Category: ACCEPTED
An Improved Measurement of the Top Quark Mass Nature {}{}{2004}. Not yet. PS

16. Direct Measurement of B(tWb)
Top Quark Properties
Single Top Production
Direct Measurement of B(tWb)
Without Systematics
With Systematics
ss (pb)
<6.4
<13.8
st (pb)
<9.0
<19.8
ss+t (pb)
<7.9
<15.8
3-jet
4-jet
1-tag 12 19
2-tag 2
Sensitivity already better than Run I
Measurement of W Helicity
New Run I measurement:
F0 = 0.56  0.31(stat+mt)  0.07 (syst)
Combined search
t-channel search
ss+t < % CL
st < % CL

17. Latest Results! (Blessed on 28/04/04..)
Study of top quark decay branching ratio
Channel: dilepton, study of ratio: BR(t->τ νb)/BRSM(t->τ νb)
Limit: < 95% C.L. With 193 pb-1
Top quark mass
Channel: single lepton+jets, method: vertex b-tag (SECVTX) and templates
Mass: (stat) (syst) GeV/c2

18. Near future of Mtop
Tevatron only (di-lepton events or lepton+jet ) from W decays
Status of inputs (preliminary):
mt=(178.0  2.7 (stat)  3.3 (syst)) GeV/c2
(latest Tevatron updated combination – RunI data)
mt=(175  17 (stat)  8 (syst)) GeV/c2
(CDF di-leptons – RunII data)
mt=( (stat)  7 (syst)) GeV/c2
(CDF lepton+jets – RunII data)
mt=( (stat)  6.5 (syst)) GeV/c2
Matter of statistics (also for the main systematics) and optimized use of the available information. Each experiment expects 500 b-tagged tt l+jets events/fb  DMtop ~ 2-3 GeV/c2 for the Tevatron combined (2-4/fb)
mt  2.5 GeV ; mW  30 MeV  mH/mH  35%
In 2009 (if upgrade is respected) from Tevatron: DMtop = 1.5 GeV !!

19. What is left before the LHC starts?
Cover topics still open: cross section, couplings, exotic, resonances,
Define a strategy for validation of the MC input models (e.g: UE modeling and subtraction, jet fragmentation properties, jet energy profiles, b-fragmentation functions..)
see M. Mangano talk at IFAE 2004
Explore the effects of changing detector parameters in evaluating the top mass.
Perform commissioning studies with top events
Contribute to simulation validation …

20. M. Mangano, IFAE, Apr 2004

21. M. Mangano, IFAE, Apr 2004

22. M. Mangano, IFAE, Apr 2004

23. Communications Speaker needed
BEACH (Beauty, Charm and Hyperons) conference in Chicago.
(june 27th-july 3rd)
We have two ATLAS talks confirmed. For one of them there are 2 options:
"LHC top physics" and "LHC electroweak physics"
The talk will be 15 and minutes (plus questions).
What we would like from the top and/or SM groups are suggestions for this talk:
both of title/topic and possible speakers.
It is conceivable we may be able to get a third (short=10') talk on whichever of
SM/top we don't choose for the longer talk, but this is not guaranteed.