DØ's Top Quark Physics Results

 

Conveners:   Andreas Jung (Fermilab) ,   Slava Sharyy (CEA-Saclay)

 

Mass

tt Cross Section

Properties

New Particles

Single Top

 

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graphics1
DØ's combination
top quark mass
January 2012

graphics2
Tevatron combination
top quark mass
July 2014

Top Quark Mass

graphics1 graphics1
Tevatron and LHC combination
top quark mass
March 2014

12 channels from DØ and CDF

Many methods

Tevatron Combination
174.34±0.37 (stat) ±0.52 (syst) GeV
= 174.34± 0.64GeV

±0.37%

9.7

arxiv:1407.2682
Figures

DØ, CDF, Atlas and CMS

Many methods

Tevatron and LHC Combination
173.34 ± 0.27 (stat) ± 0.71 (syst) GeV
= 173.34 ± 0.76 GeV

±0.44%

8.7

arXiv:1403.4427
Figures

12 channels from DØ and CDF

Many methods

Tevatron Combination
173.18 ±0.56 (stat) ±0.75 (syst) GeV
= 173.18 ± 0.94 GeV

±0.54%

5.8

PRD 86, 092003 (2012)
Figures

Lepton+jets

Matrix elements

174.98 ± 0.41(stat) ±0.41(JES) ±0.49(syst) GeV

±0.43%

9.7

PRL 113, 032002 (2014)
07/18/2014
Figures

Matrix elements

174.94 ± 0.83(stat) ±0.78(JES) ±0.96(syst) GeV

±0.85%

3.6

PRD 84 , 032004 (2011)
8/9/11
Figures

Matrix elements with
in-situ JES calibration

(NN b-tagging)

171.5 ± 1.8 (stat+JES) ± 1.1 (syst) GeV

± 1.2%

1.0

PRL 101 , 182001 (2008)
10/29/08
Figures

Ideogram
(lifetime b-tagging and
topological selection)

173.7 ± 4.4 (stat+JES) +2.1 –2.0 (syst) GeV

± 2.8%

0.42

PRD 75 , 092001 (2007)
5/11/07
Figures

Matrix element
with in-situ JES calibration
(lifetime b-tagging)

170.3 +4.1 –4.5 (stat+JES) +1.2 –1.8 (syst) GeV

+2.5% –2.8%

0.37

PRD 74 , 092005 (2006)
11/27/06
Figures

Matrix element
with in-situ JES calibration
(topological selection)

169.2 +5.0 –7.4 (stat+JES) +1.5 –1.4 (syst) GeV

+3.1% –4.5%

Lepton+jets

Pole and MS Masses
from cross section

Pole mass between 163.0 and 167.5 GeV
MS mass between 154.5 and 160.0 GeV
depending on Xsec calculation

5.3

PLB 703 , 422 (2011)
8/11/11
Figures

Lepton+jets,
dileptons, and
tau+lepton

Determined from
tt cross section

169.1  +5.9 –5.2 GeV

+3.5% –3.1%

1.0

PRD 80 , 071102 (2009)
10/19/09
Figures

Lepton+jets

Determined from
ttbar cross section

170 ± 7 GeV

± 4.1%

0.9

PRL 100 , 192004 (2008)
5/15/08
Figures

Dileptons

Neutrino weighting and
Matrix element

173.9 ± 1.9 (stat) ± 1.6 (syst) GeV

±1.4%

5.3

See below the neutrino weighting results and paper

Neutrino weighting

174.0 ± 2.4 (stat) ± 1.4 (syst) GeV

±1.6%

5.3

Phys. Rev. D 86, 051103(R) (2012)
Figures

Matrix elements

174.0 ± 1.8 (stat) ± 2.4 (syst) GeV

±1.8%

5.4

PRL 107 , 082004 (2011)
8/19/11
Figures

Neutrino weighting and
Matrix weighting

174.7 ± 4.4 (stat) ± 2.0 (syst) GeV
(includes lepton+track)

±2.8%

1.0

PRD 80 , 092006 (2009)
11/20/09
Figures

Determined from
ttbar cross section

171.5 +9.9 –8.8 (stat+syst) GeV
(includes lepton+tau)

+5.8% –5.1%

1.0

PLB 679 , 177 (2009)
7/21/09
Figures

Matrix weighting
(lifetime b-tagging
and untagged)

176.2 ± 9.2 (stat) ± 3.9 (syst) GeV

± 5.7%

0.37

PLB 655 , 7 (2007)
9/6/07
Figures
Plain-english summary

Neutrino weighting
(topological selection
and lepton+track)

179.5 ± 7.4 (stat) ± 5.6 (syst) GeV

± 5.2%

Combination of the
above two results

(various)

178.1 ± 6.7 (stat) ± 4.8 (syst) GeV

± 4.6%

 

graphics5  
September 2013

graphics6  
July 2011

Top Pair Production Cross Section
Results quoted for m top = 172.5 or 175 GeV

graphics7  
Many channels, September 2013

   graphics8
Differential cross section
January 2014

CDF and D0 combination

Different methods

7.62 ±0.42 pb     (mtop = 172.5 GeV)

±5.5%

up to 8.8

PRD 89, 072001 (2014)
01/22/14
Figures

l+jets and dilepton combination

NN b-tagging
and topological

7.56  +0.63 –0.56 (stat+syst+lumi) pb
(mtop=172.5 GeV)

+8.3% –7.4%

5.4

PLB 704 , 403 (2011)
9/17/11
Figures

NN b-tagging
and topological

8.18  +0.98 –0.87 pb     (mtop = 170 GeV)

+12% –11%

1.0

PRD 80 , 071102 (2009)
10/19/09
Figures

Lepton+jets

NN b-tagging
and topological

7.78  +0.77 –0.64 (stat+syst+lumi) pb
(mtop=172.5 GeV)

+9.9% –8.2%

5.3

PRD 84 , 012008 (2011)
7/25/11
Figures

NN b-tagging
and topological

7.62  ± 0.85 pb for mtop = 172.6 GeV
7.42  ± 0.53 (stat) ± 0.46 (syst) ± 0.45 (lumi) pb
for mtop = 175 GeV

± 11%

0.9

PRL 100 , 192004 (2008)
5/15/08
Figures

NN b-tagging
and topological
(simultaneous with B(t→Wb)/B(t→Wq),
see below)

8.18  +0.90 –0.84 (stat + syst) ± 0.50 (lumi) pb

+13% –12%

0.9

PRL 100 , 192003 (2008)
5/14/08
Figures

Muon b-tagging

7.3  +2.0 –1.8 (stat+syst) ± 0.4 (lumi) pb

+28% –25%

0.42

10/27/06
Conference note
Figures

Topological

6.4  +1.3 –1.2 (stat) ± 0.7 (syst) ± 0.4 (lumi) pb

+24% –23%

0.42

PRD 76 , 092007 (2007)
11/27/07
Figures

Lifetime tagging

6.6  ± 0.9 (stat+syst) ± 0.4 (lumi) pb

± 15%

0.42

PRD 74 , 112004 (2006)
12/26/06
Figures

Lifetime tagging

8.6  +1.6 –1.5 (stat+syst) ± 0.6 (lumi) pb

+20% –19%

0.23

PLB 626 , 35 (2005)
9/15/05
Figures
Plain-english summary

Topological

6.7  +1.4 –1.3 (stat) +1.6 –1.1 (syst) ± 0.4 (lumi) pb

+32% –26%

0.23

PLB 626 , 45 (2005)
9/15/05
Figures
Plain-english summary

Lepton+jets

Differential cross section
in top quark pT, |y| and m(ttbar)

Differential cross section and ratios with theory

9.7

Submitted to PRD
01/22/14
Figures

Differential cross section
in top quark pT

Differential cross section and ratios with theory

1.0

PLB 693 , 515 (2010)
9/15/10
Figures

Dileptons

Topological
NN b-tagging

7.36  +0.90 –0.79 (stat+syst+lumi) pb
(mtop=172.5 GeV)

+12% –11%

5.4

PLB 704 , 403 (2011)
9/14/11
Figures

NN b-tagging
and topological

7.09  +0.98 –0.92 (stat) +0.78 –0.57 (syst) +0.62 –0.49 (lumi)
(includes lepton+tau)
pb

+20% –17%

1.0

PLB 679 , 177 (2009)
7/21/09
Figures

Topological

7.4  ± 1.4 (stat) ± 0.9 (syst) ± 0.5 (lumi) pb

± 23%

0.42

PRD 76 , 052006 (2007)
9/28/07
Figures

Topological

8.6  +3.2 –2.7 (stat) ± 1.1 (syst) ± 0.6 (lumi) pb

+40% –35%

0.23

PLB 626 , 55 (2005)
9/15/05
Figures
Plain-english summary

Alljets

NN b-tagging

6.9  ±1.3 (stat) ±1.4 (syst) ±0.4 (lumi) pb

±29%

1.0

PRD 82 , 032002 (2010)
8/20/10
Figures

Lifetime tagging

4.5  +2.0 –1.9 (stat) +1.4 –1.1 (syst) ± 0.3 (lumi) pb

+55% –49%

0.41

PRD 76 , 072007 (2007)
10/19/07
Figures

Tau+jets

NN b-tagging

6.30  +1.15 −1.09 (stat) +0.72 −0.67 (syst) ±0.40 (lumi) pb

+38% −20%

1.0

PRD 82 , 071102 (2010)
10/27/10
Figures

Tau+lepton

NN b-tagging

7.3  +1.3 –1.2 (stat) +1.2 –1.1 (syst) ± 0.5 (lumi) pb

+25% –23%

2.1

7/9/08
Conference note
Figures

Lepton+track
and dileptons

NN b-tagging
and topological

6.2  ± 0.9 (stat) +0.8 –0.7 (syst) ± 0.4 (lumi) pb

+20% –19%

1.0

8/9/07
Conference note
Figures

Lepton+track

NN b-tagging

5.1  +1.6 –1.4 (stat) +0.9 –0.8 (syst) ± 0.3 (lumi) pb

+36% –32%

1.0

8/9/07
Conference note
Figures

 

 
Other Properties:

Properties of the Top Quark

Lepton+jets

Width and lifetime
(from tqb Xsec and
B(t→Wb)/B(t→Wq))

Top quark width = 2.00 +0.47 −0.43 GeV
Top quark lifetime = (3.29 +0.90 –0.63 ) × 10-25 s
0.81 < |Vtb| < 1    at 95% CL
|Vtb′| < 0.59    at 95% CL

5.4

PRD 85 , 091104 (2012)
5/4/12
Figures

Top quark width = 1.99 +0.69 −0.55 GeV
Top quark lifetime = (3.3 +1.3 –0.9 ) × 10-25 s
|Vtb′| < 0.63    at 95% CL

2.3, 1.0

PRL 106 , 022001 (2011)
1/11/11
Figures

Top and antitop
mass difference

Mtop – Mantitop = 0.8 ± 1.8 (stat) ± 0.5 (syst) GeV

3.6

PRD 84 , 052005 (2011)
9/14/11
Figures

Mtop – Mantitop = 3.8 ± 3.7 GeV

1.0

PRL 103 , 132001 (2009)
9/21/09
Figures
Nature news
Physics Today news

Top quark charge

4 e /3 excluded with 5 SD
Fraction of exotic quark pairs < 0.43  (95% CL)

5.4

Submitted to PRD-RC
07/21/14
Figures

4 e /3 excluded at 92% CL
Fraction of exotic quark pairs < 0.80  (90% CL)

0.37

PRL 98 , 041801 (2007)
1/22/07
Figures
Clarification

 

graphics5  
Mai 2014

asymmetry_Tevatron  
Inclusive asymmetries: D0 & CDF

asymmetry_Tevatron_comb  
Inclusive asymmetries: D0 & CDF (combined)

Other properties

properties of tt pair production

graphics6  
A versus m(tt)
Mai 2014

graphics7  
A versus |y_l|
March 2014

   graphics8
Al versus All (dileptons)
December 2013

Lepton+jets

Forward-backward charge asymmetry

A = (10.6 ± 3.0) %

9.7

Submitted to PRD
May 5, 2014
Figures

Lepton+jets

Asymmetry in angular distributions of leptons produced in lepton+jet final state

Al = 4.2 ± 2.3 (stat.) +1.7 -2.0(syst.)%, |y_l|<1.5
combination of l+jets and dilepton result:
Al = 4.2 ± 2.0 (stat.) ±1.4 (syst.)%

9.7

Submitted to PRD
March 7, 2014
Figures

Dileptons

Asymmetry in angular distributions of leptons produced in dilepton final state

Al = (4.4 ± 3.7 (stat) ± 1.1 (syst))%
All = (12.3 ± 5.4 (stat) ± 1.5 (syst))%.

9.7

PRD 88, 112002 (2013), arXiv:1308.6690 [hep-ex]
December 2, 2013
Figures

Lepton+jets

Lorentz invariance

Lots of limits consistent with no violation
of Lorentz invariance

5.3

PRL 108 , 261603 (2012)
6/27/12
Figures

Dileptons and combination

Forward-backward
charge asymmetry

(5.8  ± 5.3 )%   (dileptons)
(11.8  ± 3.2 )%   (dileptons + lepton+jets)

5.4

PRD 87, 011103(R) (2013)
02/04/13
Figures

Lepton+jets

(9.2  ± 3.7 )%   (reconstruction level)
(19.6  ± 6.5 )%   (unfolded)

5.4

PRD 84 , 112005 (2011)
11/7/11
Figures

(12  ± 8 (stat) ± 1 (syst) )%

0.9

PRL 100 , 142002 (2008)
4/9/08
Figures

Lepton+jets
and dileptons

Spin correlations

Correlated fraction = 0.85 ± 0.29 (stat+syst)
using matrix elements
> 3 σ significance for correlation

5.3

PRL 108 , 032004 (2012)
1/19/12
Figures

Dileptons

Correlation strength = 0.10 ± 0.45 (stat+syst)
using angular distribution templates

5.4

PLB 702 , 16 (2011)
6/29/11
Figures

Correlation strength = 0.57 ± 0.31 (stat+syst)
using matrix elements

5.4

PRL 107 , 032001 (2011)
7/14/11
Figures

 
Other Properties:

properties of top quark decay

Lepton+jets

Color flow

(Wcolor-singlet) / (Wall) = 0.56 ± 0.42
(SM = 1)

5.3

PRD 83 , 092002 (2011)
5/10/11
Figures

Top pairs →
trileptons

tZu and tZc FCNC couplings

B(t→Zq) < 3.2% at 95% CL, q = u,c

4.1

PLB 701 , 313 (2011)
6/12/11
Figures

Lepton+jets
and dileptons

B(t→Wb)/B(t→Wq)

RWb/Wq = 0.90 +0.04 (stat+syst)
|Vtb| = 0.95 ± 0.02  (if 3x3 CKM is unitary)

5.4

PRL 107 , 121802 (2011)
9/15/11
Figures

Lepton+jets

RWb/Wq = 0.97 +0.09 –0.08 (stat+syst) ,  RWb/Wq > 0.79  (95% CL)
|Vtb| > 0.89  (95% CL)  (if 3x3 CKM is unitary)

0.9

PRL 100 , 192003 (2008)
5/14/08
Figures

RWb/Wq = 1.03 +0.19 –0.17 (stat+syst)
RWb/Wq > 0.61 and |Vtb| > 0.78  (95% CL)

0.23

PLB 639 , 616 (2006)
7/24/06
Figures

Lepton+jets,
dileptons, and
tau+lepton

σ(tt→ll)/σ(tt→l+jets)
and
σ(tt→τl)/σ(tt→ll + l+jets)

Rll/lj = 0.86 +0.19 –0.17 (stat+syst)
Rτl/ll+lj = 0.97 +0.32 –0.29 (stat+syst)

1.0

PRD 80 , 071102 (2009)
10/19/09
Figures

Lepton+jets
and dileptons

W boson helicity

DØ and CDF Combination
f0 = 0.722 ±0.062 (stat) ±0.052 (syst)
f+ = −0.033 ±0.034 (stat) ±0.031 (syst)

5.4

PRD 85 , 091104 (2012)
5/4/12
Figures

f0 = 0.669 ±0.078 (stat) ±0.065 (syst)
f+ = 0.023 ±0.041 (stat) ±0.034 (syst)

5.4

PRD 83 , 032009 (2011)
11/30/10
Figures

f0 = 0.425 ±0.166 (stat) ±0.102 (syst)
f+ = 0.119 ±0.090 (stat) ±0.053 (syst)

1.0

PRL 100 , 062004 (2008)
2/14/08
Figures
Plain-english summary

f+ = 0.056 ±0.080 (stat) ±0.057 (syst)
f+ < 0.23  (95% CL)

0.37

PRD 75 , 031102(R) (2007)
2/5/07
Figures

Lepton+jets

Fraction of right-handed W's in top decays = f+
f+= 0.00 ± 0.13 (stat) ± 0.07 (syst)
f+ < 0.25  (95% CL)

0.23

PRD 72 , 011104 (2005)
7/29/05
Figures
Plain-english summary

 
Other Properties:

top quark couplings

Top pairs →
trileptons

tZu and tZc FCNC couplings

B(t→Zq) < 3.2% at 95% CL, q = u,c

4.1

PLB 701 , 313 (2011)
6/12/11
Figures

Single top
and tt
lepton+jets

Wtb couplings

Limits set on
left-handed and right-handed
vector and tensor couplings

5.4

PLB 713 , 165 (2012)
5/25/12
Figures

Single top
lepton+jets

Limits set on
left-handed and right-handed
vector and tensor couplings

5.4

PLB 703 , 21 (2012)
1/16/12
Figures

 

Limits set on
left-handed and right-handed
vector and tensor couplings

1.0

PRL 102 , 092002 (2009)
3/4/09
Figures

Single top
lepton+jets

Limits set on
left-handed and right-handed
vector and tensor couplings

0.9

PRL 101 , 221801 (2008)
11/25/08
Figures

Single top
lepton+jets

tgu and tgc FCNC couplings

σ tgu < 0.20 pb,   B(t→gu) < 2.0 × 10 -4
σ tgc < 0.27 pb,   B(t→gc) < 3.9 × 10 -3

2.3

PLB 693 , 81 (2010)
8/6/10
Figures

κ g c /Λ < 0.15 TeV -1
κ g u /Λ < 0.037 TeV -1 at 95% CL

0.23

PRL 99 , 191802 (2007)
11/6/07
Figures

 

 
Searches for New Particles

Lepton+jets

tt resonances from
leptophobic Z′ bosons

MZ′ < 835 GeV
excluded at 95% CL for ΓZ′ = 1.2% MZ′

5.3

PRD 85 , 051101 (2012)
3/14/12
Figures

MZ′ < 700 GeV
excluded at 95% CL for ΓZ′ = 1.2% MZ′

0.9

PLB 668 , 98 (2008)
8/22/08
Figures

Lepton+jets

Fourth generation
t′t′ →WqWq

Mt′ < 285 GeV
excluded at 95% CL

5.3

PRL 107 , 082001 (2011)
8/16/11
Figures

Lepton+jets
dileptons, and
tau+lepton

Top decay to
charged Higgs boson

Limits on B(t→H+b) with hadronic and tauonic decays

1.0

PLB 682 , 278 (2009)
11/12/09
Figures

Limits on B(t→H+b) with tauonic and leptophobic decays

1.0

PRD 80 , 071102 (2009)
10/19/09
Figures

Lepton+jets

Limits on B(t→H+b) with tauonic decays

0.9

PRD 80 , 051107 (2009)
9/30/09
Figures

Lepton+jets

Scalar top
pair production

Limits on scalar top masses between 130 to 190 GeV
and chargino masses of 90 to 150 GeV

0.9

PLB 674 , 4 (2009)
2/20/09
Figures
Plain-english summary

Lepton+jets

SM Higgs
produced with tt,
with H0→bb

σ(ttH) < 64 × SM value for MHiggs = 115 GeV
MH < 133 GeV for mt′= 400 GeV and MG′ = 800 GeV at 95% CL

2.1

3/13/09
Conference note
Figures

Single top
lepton+jets

H+→tb

Type I 2HDM model excluded for
M(H + = 180–185 GeV at 95% CL
and tan(β) = 20–70 approx
and limits on Types II and III set

0.9

PRL 102 , 191802 (2009)
5/14/09
Figures

Single top
lepton+jets

W′→tb

M(W′(left)→lν,qq) > 863 GeV
M(W′(right)→lν,qq) > 885 GeV
M(W′(left,right)→lν,qq) > 916 GeV
M(W′(right)→qq) > 890 GeV at 95% CL

2.3

PLB 699 , 145 (2011)
3/31/11
Figures

M(W′(left)→lν,qq) > 731 GeV
M(W′(right)→lν,qq) > 739 GeV
M(W′(right)→qq) > 768 GeV at 95% CL

0.9

PRL 100 , 211803 (2008)
5/30/08
Figures

M(W′(right)→ln,qq) > 630 GeV
M(W′(right)→qq) > 670 GeV at 95% CL

0.23

PLB 641 , 423 (2006)
9/28/06
Figures
Plain-english summary
Analysis details

 

graphics9
s+t channel, June 2013

graphics9
t-channel, June 2013

 
Single Top Quark
Production

graphics9
s-channel, February 2014

graphics10
June 2013

Lepton+jets

s-channel observation

Tevatron combination
σ(tb) = 1.29 +0.26 -0.24

tb: +20% -19% (6.3SD evidence)

up to 9.7

PRL 112, 231803 (2014)
02/21/2014
Figures

s-channel evidence
t channel measurement
s+t channel measurement

σ(tb) = 1.10 +0.33 -0.31
σ(tqb) = 3.07 +0.53 -0.49
σ(tqb+tb) = 4.11 +0.59 -0.55
0.92 < |Vtb| ≤ 1 at 95% CL

tb: +30% -28% (3.7SD evidence)
tqb: +17% -16% (7.7SD)
tb+tqb: +14% -13%

9.7

PLB 726, 656 (2013)
11/04/2013
Figures

Wtb couplings
(single top and
tt W helicity)

Limits set on
left-handed and right-handed
vector and tensor couplings

95% C.L.

5.4

PLB 713 , 165 (2012)
5/25/12
Figures

Width and lifetime
from tqb Xsec and
B(t→Wb)/B(t→Wq)

Top quark width = 2.00 +0.47 −0.43 GeV
Top quark lifetime = (3.29 +0.90 –0.63 ) × 10-25 s
0.81 < |Vtb| < 1    at 95% CL
|Vtb′| < 0.59    at 95% CL

+24% −22%
+27% −19%

PRD 85 , 091104 (2012)
5/4/12
Figures

Wtb couplings

Limits set on
left-handed and right-handed
vector and tensor couplings

95% C.L.

Phys. Lett. B 708:21-26, 2012
1/16/12
Figures

t+s channels together and separately and |Vtb|

σ(tqb+tb) = 3.43 +0.73 −0.74 pb
0.79 < |Vtb| ≤ 1 at 95% CL

± 21%

PRD 84 , 112001 (2011)
12/5/11
Figures

t-channel and s-channel
Xsec measurements
and t vs. s 2d plot

σ(tqb) = 2.90 ± 0.59 pb
(5.5 std. dev. significance)

σ(tb) = 0.98 ± 0.63 pb

± 20%

± 64%

PLB 705 , 313 (2011)
10/20/11
Figures
Supplemental material

Tau+jets

Xsec limit and
combination with
DØ's observation measurement

σ(tb+tqb) = 3.84 +0.89 –0.83 pb
(all channels combined)

+23% –22%

4.8

PLB 690 , 5 (2010)
5/6/10
Figures

Lepton+jets

Combination of DØ's and CDF's results:
cross section and |Vtb|

σ(tb+tqb) = 2.76 +0.58 –0.47 pb

|V
tb| > 0.77   at 95% C.L.    (prior: 0 ≤ |Vtb|2 ≤ 1)
|Vtbf1L| = 0.88 ± 0.07    (prior: |Vtb|2 ≥ 0)

 
+21% –17%
 
 

2.3, 3.2

8/15/09
Technical memo
Figures

W′→tb search

M(W′(left)→lν,qq) > 863 GeV
M(W′(right)→lν,qq) > 885 GeV
M(W′(left,right)→lνqq) > 916 GeV
M(W′(right)→qq) > 890 GeV

95% C.L.

2.3

PLB 699 , 145 (2011)
3/31/11
Figures

Width and lifetime
from tqb Xsec and
B(t→Wb)/B(t→Wq)

Top quark width = 1.99 +0.69 −0.55 GeV
Top quark lifetime = (3.3 +1.3 –0.9 ) × 10-25 s
|Vtb′| < 0.63    at 95% CL

+35% −28%
+39% −27%

2.3, 1.0

PRL 106 , 022001 (2011)
1/11/11
Figures

tgu and tgc FCNC couplings

σ tgu < 0.20 pb,   B(t→gu) < 2.0 × 10 -4
σ tgc < 0.27 pb,   B(t→gc) < 3.9 × 10 -3

95% C.L.

2.3

PLB 693 , 81 (2010)
8/11/10
Figures

t-channel and s-channel
Xsec measurements
and t vs. s 2d plot

σ(tqb+X) = 3.14 +0.94 –0.80 pb
(4.8 std. dev. significance)
σ(tb+X) = 1.05
± 0.81 pb

+30% –25%

±77%

PLB 682 , 363 (2010)
11/19/09
Figures

Analyses with
boosted decsion trees,
Bayesian neural networks,
matrix elements,
and their combination

σ(tb+tqb) = 3.94 ± 0.88 pb
5.0 standard deviation significance
(mtop = 170 GeV)

|Vtb| > 0.78   at 95% C.L.    (prior: 0 ≤ |Vtb|2 ≤ 1)
|Vtbf1L| = 1.07 ± 0.12    (prior: |Vtb|2 ≥ 0)

± 22%
 
 
 
 


"Observation of
Single Top-Quark
Production"


PRL 103 , 092001 (2009)
8/24/09
Figures
Results web page (plots for talks)
SPIRES TOPCITE=100+

Lepton+jets

H+→tb search

Type I 2HDM model excluded for
M(H + = 180–185 GeV
and tan(β) = 20–70 approx
and limits on Types II and III set

95% C.L.

0.9

PRL 102 , 191802 (2009)
5/14/09
Figures

Wtb couplings
(single top and
tt W helicity)

Limits set on
left-handed and right-handed
vector and tensor couplings

95% C.L.

PRL 102 , 092002 (2009)
3/4/09
Figures

Wtb couplings

Limits set on
left-handed and right-handed
vector and tensor couplings

95% C.L.

PRL 101 , 221801 (2008)
11/25/08
Figures

W′→tb search

M(W′(left)→lν,qq) > 731 GeV
M(W′(right)→lν,qq) > 739 GeV
M(W′(right)→qq) > 768 GeV

95% C.L.

PRL 100 , 211803 (2008)
5/30/08
Figures

Combination of
DT, new-ME,
and new-BNN

σ(tb+X,tqb+X) = 4.7 ± 1.3 pb
(3.6 std. dev. significance)

± 28%

PRD 78 , 012005 (2008)
7/14/08
Figures
SPIRES TOPCITE=50+

Matrix elements

 
σ(tb+X,tqb+X) = 4.8
+1.6 –1.4 pb
 

+33% –29%

Bayesian neural networks

 
σ(tb+X,tqb+X) = 4.4
+1.6 –1.4 pb
 

+36% –32%

Boosted decision trees

σ(tb+X,tqb+X) = 4.9 ± 1.4 pb
(3.4 std. dev. significance)


s-channel:  σ(tb+X) = 1.0 ± 0.9 pb
t-channel:  σ(tqb+X) = 4.2 +1.8 –1.4 pb

± 29%


±90%
+43% –33%

"Evidence for Production
of Single Top Quarks"


PRL 98 , 181802 (2007)
5/1/07
Figures
Plain-english summary
Analysis details
SPIRES TOPCITE=100+

Matrix elements

 
σ(tb+X,tqb+X) = 4.6
+1.8 –1.5 pb
 

+39% –33%

Bayesian neural networks

 
σ(tb+X,tqb+X) = 5.0
± 1.9 pb
 

± 38%

Lepton+jets

tgu and tgc FCNC couplings

κ g c /Λ < 0.15 TeV -1
κ g u /Λ < 0.037 TeV -1

95% C.L.

0.23

PRL 99 , 191802 (2007)
11/6/07
Figures

W′→tb search

M(W′(right)→lν,qq) > 630 GeV
M(W′(right)→qq) > 670 GeV

95% C.L.

PLB 641 , 423 (2006)
9/28/06
Figures
Plain-english summary
Analysis details

Cuts

s-channel:  σ(tb) < 10.6 pb
t-channel:  σ(tqb) < 11.3 pb

95% C.L.

PRD 75 , 092007 (2007)
5/29/07
Figures
(Includes NN result below)

Neural networks

s-channel:  σ(tb) < 6.4 pb
t-channel:  σ(tqb) < 5.0 pb

95% C.L.

PLB 622 , 265 (2005)
7/21/05
Figures
Plain-english summary
Analysis details
SPIRES TOPCITE=50+