1. University of Tsukuba, Japan Particle Physics Phenomenology,
2019/2/23
Top, Electroweak and Bottom Physics at CDF
Top quark production x-section, mass
W boson mass, gauge boson pair production
Bs oscillations, B → PP
Fumihiko UKEGAWA
CDF Collaboration
University of Tsukuba, Japan
KEK Theory Meeting on
Particle Physics Phenomenology,
KEKPH2007
March 1 - 3, 2007

2. Top Quark Observed by CDF and DØ in Run-I data, 100 pb-1.
2019/2/23
Top Quark
Observed by CDF and DØ in Run-I data, 100 pb-1.
Tens of events reconstructed,
measurements limited by statistics.
Run-II data now allow more detailed studies.

3. Top quark pair production
2019/2/23
Top quark pair production
Lepton + jet channel
Jet multiplicity distribution

4. Top quark production cross section
2019/2/23
Top quark production cross section
Di-lepton channel
All-hadronic channel

5. Top quark production cross section
2019/2/23
Top quark production cross section
All channels, techniques
Good agreement with theory

6. Top Quark Mass Combine with W mass, probe Higgs indirectly.
2019/2/23
Top Quark Mass
Combine with W mass,
probe Higgs indirectly.
Run-I measurements
Run-II expectations, ~3 GeV
CDF/DØ
2 fb-1 goal
hep-ex/

7. Top mass measurement techniques
2019/2/23
Top mass measurement techniques
Lepton + jet channel
Matrix element method
Template method
Reconstruct top “mass” from observed quantities (lepton, jets).
Compare to MC distributions
Utilize maxima information of the event, such as
Parton level cross section
parton distribution function
Evaluate a probability density as a function of true mtop,
multiply prob. for all events
In any method, understanding the jet energy scale is crucial and a dominant systematic uncertainty.

8. Top mass measurement : jet energy scale (JES)
2019/2/23
Top mass measurement : jet energy scale (JES)
In situ calibration :
Adjust the jet energy scale so as to get the correct W mass
Effectively treated as a stat error.
Matrix element method sample
Stat + JES
Similarly,
with the template method :

9. Top mass measurements : dilepton and all-hadronic channels
2019/2/23
Top mass measurements : dilepton and all-hadronic channels
Di-lepton channel
All-hadronic channel
Matrix element method
Template method
Similarly,
with the templete method :

10. Top Quark Mass Past Future Present Aiming at <1% precision CDF / DØ
2019/2/23
CDF / DØ
2 fb-1 goal,
~3 GeV
Top Quark Mass
Past
Future
Present
Aiming at <1% precision

11. 2019/2/23

12. Understanding the detector
2019/2/23
Understanding the detector
Bremsstrahlung tail

13. W-boson Mass Measurement
2019/2/23
mT fit
Electrons
pT fit
mT fit
Muons
ET fit

14. W boson mass uncertainties / result
2019/2/23
CDF RUN II
PRELIMINARY

15. Higgs Mass? SM Higgs mass Or, SUSY Higgs favored? CDF/DØ 2 fb-1 goal
2019/2/23
Higgs Mass?
SUSY Higgs favored?
CDF/DØ
2 fb-1 goal
SM Higgs mass
Or,

16. Gauge boson pair production t
2019/2/23
Gauge boson pair production t
Unified electroweak theory :
Non-Abelian gauge structure.
 self-coupling among gauge bosons.

17. Photons detected > 7 GeV Check 3-body mass (l n g) for Brems.
2019/2/23
W + Photon Production
Photons detected > 7 GeV
Check 3-body mass (l n g) for Brems.
More direct test : angular distributions  radiation amplitude zero

18. 2019/2/23
First observation

19. B Physics
2019/2/23

20. Crucial information on the unitarity triangle of the CKM matrix,
2019/2/23
Crucial information on the unitarity triangle of the CKM matrix,
length of one of the sides

21. 2019/2/23

22. One of the challenges : resolving very quick oscillations
2019/2/23
One of the challenges : resolving very quick oscillations
Proper time resolution
Real data, hadromic mode
Roughly 20 times better than Belle/BaBar

23. 2019/2/23

24. Impact on the triangle
2019/2/23
Summer 2005
Fall 2006

25. 2019/2/23
Penguin
Tree

26. Statistical separation using mass, kinematics, dE/dX
2019/2/23
Expectation from MC
Combinatorial background
Partially
Reconstructed
Statistical separation
using mass, kinematics,
dE/dX

27. 2019/2/23

28. Three new modes observed
2019/2/23
Rarer modes MC
Three new modes observed

29. Agree, though errors are large
2019/2/23
Mode 2
Mode 1
Gronau, PL B 492, 297 (2000)
Agree, though errors are large
Lipkin, PL B 621, 126, 2005

30. 2019/2/23
Summary

31. 2019/2/23
Backup slides

32. Future : look for CP-violation, ~0 expected in SM, arg(Vts).
2019/2/23
260 pb-1
Future : look for CP-violation, ~0 expected in SM, arg(Vts).

33. 2019/2/23
1 fb-1

34. FCNC Vtd for B0d, Vts for B0s Helicity suppressed. B.F. very small.
2019/2/23 b
d, s t w l+ l-
Z/g
FCNC
Vtd for B0d, Vts for B0s
Helicity suppressed.
B.F. very small.
SM predictions for B.F.

35. B.R. < 3.0 x 10-8 for B0d B.R. < 1.0 x 10-7 for B0s @ 95% C.L.
2019/2/23
Two and one candidates
in the B0d and B0s mass windows.
B.R. < 3.0 x 10-8 for B0d
B.R. < 1.0 x for B0s
@ 95% C.L.
Preliminary.
CDF Run-I limits :
B.R. < 8.6 x 10-7 for B0d
B.R. < 2.6 x 10-6 for B0s
PRD 57, 3811 (1998)

36. W helicity in top decays
2019/2/23
either left-handed (WL) or longitudinally polarized (W0)
Lepton angular distribution in
W rest frame :
Backward peak for left-handed W.
 smaller momentum in lab.
DØ reconstructs cosf = -cosq*
cos()
~160 pb-1
F+ = 0
F+ = 0.3
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