BSM Higgs Boson Searches at the Tevatron Collidermctp/SciPrgPgs/events/2010/Higgs/speaker...
Transcript of BSM Higgs Boson Searches at the Tevatron Collidermctp/SciPrgPgs/events/2010/Higgs/speaker...
BSM Higgs Boson Searches at the Tevatron Collider
Frank FilthautRadboud University Nijmegen / Nikhef
for the D0 and CDF Collaborations
MCTP Higgs Symposium, May 13-15, 2010
ContentsMSSM
Phenomenology
Neutral Higgs → bb
Neutral Higgs →τ+τ-
Charged Higgs bosons
Fermiophobic Higgs Bosons: H →γγSM Extension to Four Fermion Generations
NMSSM
Phenomenology
Charged Higgs bosons
Light neutral Higgs bosons
2
ContentsMSSM
Phenomenology
Neutral Higgs → bb
Neutral Higgs →τ+τ-
Charged Higgs bosons
Fermiophobic Higgs Bosons: H →γγSM Extension to Four Fermion Generations
NMSSM
Phenomenology
Charged Higgs bosons
Light neutral Higgs bosons
2
Many details omittedtheory references (computations use FeynHiggs)detailed discussions of statistical treatment, systematics
MSSM Higgs Phenomenology: Tree LevelHiggs bosons in the MSSM: “Type-II” Two-Higgs Doublet Model
5 Higgs bosons: H, h, A (neutral), H± (charged)
dependence on 2 new parameters: MA,
Masses:
3
Hu =�
H+u
H0u
�, Hd =
�H0
d
H−d
�
tanβ ≡ vu/vd
m2h,H =
12
�m
2A + m
2Z ∓
�(m2
A− m2
Z)2 + 4m2
Zm2
Asin2(2β)
�
m2H± = m
2A + m
2W
MSSM Higgs Phenomenology: Tree LevelHiggs bosons in the MSSM: “Type-II” Two-Higgs Doublet Model
5 Higgs bosons: H, h, A (neutral), H± (charged)
dependence on 2 new parameters: MA,
Masses:
mh < mZ (!)
Couplings:
neutral:
3
SM particle type h coupling H coupling A coupling
up-type quarks cosαsinβ
sinαsinβ
cotβ
down-type quarks, �± − sinαcosβ
cosαcosβ tanβ
W, Z bosons sin(β − α) cos(β − α) 0
Hu =�
H+u
H0u
�, Hd =
�H0
d
H−d
�
tanβ ≡ vu/vd
H±tb coupling ∼ Vtbmt cotβ(1 − γ5) + mb tanβ(1 + γ5) α: CP-even Higgsmixing parameter
Beyond Tree LevelSubstantial corrections (e.g. to mh, from top (s)quark loops)
mass/coupling dependence on other SUSY parameters
Embodied in several scenarios (allowing to evade LEP bounds)
4
0 50 100 150 200 250 300Hu [GeV]
0
20
40
60
Hd [
GeV
]
Figure 7.1: A contour map of the Higgs potential, for a typical case with tan β ≈ − cot α ≈ 10.The minimum of the potential is marked by +, and the contours are equally spaced equipotentials.Oscillations along the shallow direction, with H0
u/H0d ≈ 10, correspond to the mass eigenstate h0, while
the orthogonal steeper direction corresponds to the mass eigenstate H0.
∆(m2h0) =
h0
t
+h0
t̃
+ h0
t̃
Figure 7.2: Contributions to the MSSM lightest Higgs mass from top-quark and top-squark one-loopdiagrams. Incomplete cancellation, due to soft supersymmetry breaking, leads to a large positivecorrection to m2
h0 in the limit of heavy top squarks.
and is traditionally chosen to be negative; it follows that −π/2 < α < 0 (provided mA0 > mZ). TheFeynman rules for couplings of the mass eigenstate Higgs scalars to the Standard Model quarks andleptons and the electroweak vector bosons, as well as to the various sparticles, have been worked outin detail in ref. [165, 166].
The masses of A0, H0 and H± can in principle be arbitrarily large since they all grow with b/ sin(2β).In contrast, the mass of h0 is bounded above. From eq. (7.20), one finds at tree-level [167]:
mh0 < mZ | cos(2β)| (7.23)
This corresponds to a shallow direction in the scalar potential, along the direction (H0u−vu,H0
d −vd) ∝(cos α,− sin α). The existence of this shallow direction can be traced to the fact that the quartic Higgscouplings are given by the square of the electroweak gauge couplings, via the D-term. A contour mapof the potential, for a typical case with tan β ≈ − cot α ≈ 10, is shown in figure 7.1. If the tree-levelinequality (7.23) were robust, the lightest Higgs boson of the MSSM would have been discovered atLEP2. However, the tree-level formula for the squared mass of h0 is subject to quantum correctionsthat are relatively drastic. The largest such contributions typically come from top and stop loops, asshown‡ in fig. 7.2. In the simple limit of top squarks that have a small mixing in the gauge eigenstatebasis and with masses mt̃1
, mt̃2much greater than the top quark mass mt, one finds a large positive
one-loop radiative correction to eq. (7.20):
∆(m2h0) =
3
4π2cos2α y2
t m2t ln
(mt̃1
mt̃2/m2
t
). (7.24)
This shows that mh0 can exceed the LEP bounds.‡In general, one-loop 1-particle-reducible tadpole diagrams should also be included. However, they just cancel against
tree-level tadpoles, and so both can be omitted, if the VEVs vu and vd are taken at the minimum of the loop-correctedeffective potential (see previous footnote).
68
Scenario mmax
h no-mixing gluophobic small αeff
t̃1, t̃2 mixing parameter Xt 2 TeV 0 -0.75 TeV -1.1 TeV
Higgs bilinear coupling µ ±200 GeV ±200 GeV ±300 GeV 2 TeV
SU(2) gaugino mass M2 200 GeV 200 GeV 300 GeV 500 GeV
gaugino mass mg̃ 0.8 TeV 1.6 TeV 0.5 TeV 0.5 TeV
sfermion SUSY breaking parm. MSUSY 1 TeV 2 TeV 0.35 TeV 0.8 TeV
tuned to maximize mh
suppressed h → bb, ττ
suppressed gg → h
between top squarks
Beyond Tree LevelSubstantial corrections (e.g. to mh, from top (s)quark loops)
mass/coupling dependence on other SUSY parameters
Embodied in several scenarios (allowing to evade LEP bounds)
4
0 50 100 150 200 250 300Hu [GeV]
0
20
40
60
Hd [
GeV
]
Figure 7.1: A contour map of the Higgs potential, for a typical case with tan β ≈ − cot α ≈ 10.The minimum of the potential is marked by +, and the contours are equally spaced equipotentials.Oscillations along the shallow direction, with H0
u/H0d ≈ 10, correspond to the mass eigenstate h0, while
the orthogonal steeper direction corresponds to the mass eigenstate H0.
∆(m2h0) =
h0
t
+h0
t̃
+ h0
t̃
Figure 7.2: Contributions to the MSSM lightest Higgs mass from top-quark and top-squark one-loopdiagrams. Incomplete cancellation, due to soft supersymmetry breaking, leads to a large positivecorrection to m2
h0 in the limit of heavy top squarks.
and is traditionally chosen to be negative; it follows that −π/2 < α < 0 (provided mA0 > mZ). TheFeynman rules for couplings of the mass eigenstate Higgs scalars to the Standard Model quarks andleptons and the electroweak vector bosons, as well as to the various sparticles, have been worked outin detail in ref. [165, 166].
The masses of A0, H0 and H± can in principle be arbitrarily large since they all grow with b/ sin(2β).In contrast, the mass of h0 is bounded above. From eq. (7.20), one finds at tree-level [167]:
mh0 < mZ | cos(2β)| (7.23)
This corresponds to a shallow direction in the scalar potential, along the direction (H0u−vu,H0
d −vd) ∝(cos α,− sin α). The existence of this shallow direction can be traced to the fact that the quartic Higgscouplings are given by the square of the electroweak gauge couplings, via the D-term. A contour mapof the potential, for a typical case with tan β ≈ − cot α ≈ 10, is shown in figure 7.1. If the tree-levelinequality (7.23) were robust, the lightest Higgs boson of the MSSM would have been discovered atLEP2. However, the tree-level formula for the squared mass of h0 is subject to quantum correctionsthat are relatively drastic. The largest such contributions typically come from top and stop loops, asshown‡ in fig. 7.2. In the simple limit of top squarks that have a small mixing in the gauge eigenstatebasis and with masses mt̃1
, mt̃2much greater than the top quark mass mt, one finds a large positive
one-loop radiative correction to eq. (7.20):
∆(m2h0) =
3
4π2cos2α y2
t m2t ln
(mt̃1
mt̃2/m2
t
). (7.24)
This shows that mh0 can exceed the LEP bounds.‡In general, one-loop 1-particle-reducible tadpole diagrams should also be included. However, they just cancel against
tree-level tadpoles, and so both can be omitted, if the VEVs vu and vd are taken at the minimum of the loop-correctedeffective potential (see previous footnote).
68
Scenario mmax
h no-mixing gluophobic small αeff
t̃1, t̃2 mixing parameter Xt 2 TeV 0 -0.75 TeV -1.1 TeV
Higgs bilinear coupling µ ±200 GeV ±200 GeV ±300 GeV 2 TeV
SU(2) gaugino mass M2 200 GeV 200 GeV 300 GeV 500 GeV
gaugino mass mg̃ 0.8 TeV 1.6 TeV 0.5 TeV 0.5 TeV
sfermion SUSY breaking parm. MSUSY 1 TeV 2 TeV 0.35 TeV 0.8 TeV
tuned to maximize mh
suppressed h → bb, ττ
suppressed gg → h
between top squarks
Main focus of Tevatron analyses
0
20
40
60
80
100
120
140
160
0 20 40 60 80 100 120 1400
20
40
60
80
100
120
140
160
mh (GeV/c
2)
mA
(G
eV/c
2)
Excludedby LEP
TheoreticallyInaccessible
mh-max
1
10
0 20 40 60 80 100 120 140
1
10
mh (GeV/c
2)
tan!
Excludedby LEP
TheoreticallyInaccessible
mh-max
1
10
0 200 400
1
10
mA
(GeV/c2)
tan!
Excludedby LEP
mh-max
1
10
0 200 400
1
10
mH± (GeV/c
2)
tan!
Excludedby LEP
mh-max
Theo
reti
call
y I
nac
cess
ible
0
20
40
60
80
100
120
140
160
0 20 40 60 80 100 120 1400
20
40
60
80
100
120
140
160
mh (GeV/c
2)
mA
(G
eV/c
2)
Excludedby LEP
TheoreticallyInaccessible
No Mixing
1
10
0 20 40 60 80 100 120 140
1
10
mh (GeV/c
2)
tan!
Excludedby LEP
TheoreticallyInaccessible
No Mixing
1
10
0 200 400
1
10
mA
(GeV/c2)
tan!
Excludedby LEP
No Mixing
1
10
0 200 400
1
10
mH± (GeV/c
2)
tan!
Excludedby LEP
No Mixing
Th
eore
tica
lly
In
acce
ssib
le
MSSM Higgs Production at the TevatronLEP analyses focused on ZH associated production ! exclusion mainly at low tanβ
5
MSSM Higgs Production at the TevatronLEP analyses focused on ZH associated production ! exclusion mainly at low tanβMost of the Tevatron programme focuses on high tanβ ! complementarity: different production mechanisms
5
100 150 200 250M [GeV]
10-1
100
101
102
103
104
pro
duct
ion
cros
s se
ctio
n [fb
]
hHA
Tevatron, s = 1.96 TeVmh
max, tan = 5
(bb)
gg
W/Z
tt
100 150 200 250M [GeV]
10-1
100
101
102
103
104
105
106
pro
duct
ion
cros
s se
ctio
n [fb
]
hHA
Tevatron, s = 1.96 TeVmh
max, tan = 40
(bb)
gg
W/Z
tt
(Tev4LHC WG)
MSSM Higgs Production at the TevatronLEP analyses focused on ZH associated production ! exclusion mainly at low tanβMost of the Tevatron programme focuses on high tanβ ! complementarity: different production mechanisms
5
100 150 200 250M [GeV]
10-1
100
101
102
103
104
pro
duct
ion
cros
s se
ctio
n [fb
]
hHA
Tevatron, s = 1.96 TeVno mixing, tan = 5
(bb)
gg
qqW/Z
tt
100 150 200 250M [GeV]
10-1
100
101
102
103
104
105
106
pro
duct
ion
cros
s se
ctio
n [fb
]
hHA
Tevatron, s = 1.96 TeVno mixing, tan = 40
(bb)
gg
W/Z
tt
(Tev4LHC WG)
(GeV)Am100 120 140 160 180 200 220 240
100
150
200
250
300=30!=200 GeV, tanµmhmax scenario,
h
H
A
±H
(GeV)Am100 120 140 160 180 200 220 240
m (G
eV)
100
150
200
250
300=3!=200 GeV, tanµmhmax scenario,
h
H
A
±H
MSSM Higgs Production at the TevatronLEP analyses focused on ZH associated production ! exclusion mainly at low tanβMost of the Tevatron programme focuses on high tanβ ! complementarity: different production mechanisms
5
(GeV)Am100 120 140 160 180 200 220 240
100
150
200
250
300=30!=200 GeV, tanµnomixing scenario,
h
H
A
±H
(GeV)Am100 120 140 160 180 200 220 240
m (G
eV)
100
150
200
250
300=3!=200 GeV, tanµnomixing scenario,
h
H
A
±H
MSSM Higgs Production at the TevatronLEP analyses focused on ZH associated production ! exclusion mainly at low tanβMost of the Tevatron programme focuses on high tanβ ! complementarity: different production mechanisms
5
MSSM Higgs Production at the TevatronLEP analyses focused on ZH associated production ! exclusion mainly at low tanβMost of the Tevatron programme focuses on high tanβ ! complementarity: different production mechanisms
General feature:
masses, production cross sections for A, h/H very similar ! “Φ”
production of “other CP-even boson (H/h) ~ negligible
5
Analyses don’t attempt to identify individual Higgs bosons, but look for an overall excess instead
bΦ → bbbLargest branching fraction (~90%) ... but need extra b jet to be visible
triple b-tagged data, look for excess in invariant mass spectrum of leading b-tagged jets
emphasis on understanding multijet background
6
+
update from 1.9 fb-1
bb b b
bΦ → bbbLargest branching fraction (~90%) ... but need extra b jet to be visible
triple b-tagged data, look for excess in invariant mass spectrum of leading b-tagged jets
emphasis on understanding multijet background
CDF analysis (2.5 fb-1):
create bkgd template shapes from double tagged sample (also in mvtx variable: extra discrimination)
template fit including also signal
in absence of significant excess, use likelihood ratio to derive limits
6
+
dijet mass m12 (GeV/c2)
frac
tion/
(15
GeV
/c2 )
bbBbBbbbXbCbbQb
CDF Run II PreliminaryBackground Templates
0
0.025
0.05
0.075
0.1
0.125
0.15
0.175
0.2
0.225
50 100 150 200 250 300 350
update from 1.9 fb-1
bb b b
bΦ → bbbLargest branching fraction (~90%) ... but need extra b jet to be visible
triple b-tagged data, look for excess in invariant mass spectrum of leading b-tagged jets
emphasis on understanding multijet background
CDF analysis (2.5 fb-1):
create bkgd template shapes from double tagged sample (also in mvtx variable: extra discrimination)
template fit including also signal
in absence of significant excess, use likelihood ratio to derive limits
6
+
flavor separator xtags (GeV/c2)
frac
tion/
(1 G
eV/c
2 )
bbBbBbbbXbCbbQb
CDF Run II PreliminaryBackground Templates
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0 1 2 3 4 5 6 7 8 9
update from 1.9 fb-1
bb b b
bΦ → bbbLargest branching fraction (~90%) ... but need extra b jet to be visible
triple b-tagged data, look for excess in invariant mass spectrum of leading b-tagged jets
emphasis on understanding multijet background
CDF analysis (2.5 fb-1):
create bkgd template shapes from double tagged sample (also in mvtx variable: extra discrimination)
template fit including also signal
in absence of significant excess, use likelihood ratio to derive limits
6
+
dijet mass m12 (GeV/c2)
frac
tion/
(15
GeV
/c2 )
mH = 90 GeV/c2
mH = 120 GeV/c2
mH = 150 GeV/c2
mH = 180 GeV/c2
mH = 210 GeV/c2
CDF Run II PreliminarySignal Templates
0
0.05
0.1
0.15
0.2
0.25
0.3
50 100 150 200 250 300 350
update from 1.9 fb-1
bb b b
bΦ → bbbLargest branching fraction (~90%) ... but need extra b jet to be visible
triple b-tagged data, look for excess in invariant mass spectrum of leading b-tagged jets
emphasis on understanding multijet background
CDF analysis (2.5 fb-1):
create bkgd template shapes from double tagged sample (also in mvtx variable: extra discrimination)
template fit including also signal
in absence of significant excess, use likelihood ratio to derive limits
6
+
dijet mass m12 (GeV/c2)
even
ts/(1
5 G
eV/c
2 ) CDF Run II PreliminaryBest Fit (with signal template)
over
flow
bbBbBbbbXbCbbQbmH=150CDF 2.5/fb
0
200
400
600
800
1000
1200
1400
1600
1800
50 100 150 200 250 300 350
Q ≡ L(data|s + b̂)
L(data| ˆ̂b)
update from 1.9 fb-1
bb b b
bΦ → bbb (2)For high tanβ, the decay widths ΓΦ become substantial
resonance less easily distinguished ! loss of sensitivity
7
mA (GeV/c2)
tan
CDF Run II Preliminary (2.5/fb)
mh max scenario, ! = -200 GeV ( b=-0.21)
Higgs width included
expected limit1 band2 bandobserved limit
95" C.L. upper limits
020406080
100120140160180200
100 120 140 160 180 200
∆b ∝ tanβ · µ
bΦ → bbb (3)D0 analysis (2.6 fb-1):
separation into 3/4/5-jet samples
flavour composition estimated using multiple b-tagging criteria
likelihood discriminant to improve S/B ratio
using topological information
obtain from double-tagged data, use to predict triple-tagged bkgd
8
D =Psig(�x)
Psig(�x) + Pbkg(�x)
D0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1 -1DØ Prelim., L=1.61 fb
3 jets exclusiveLow-mass LH
DØ DataExp. bkg Heavy flav.Higgs Signal
D0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1 -1DØ Prelim., L=1.61 fb
3 jets exclusiveHigh-mass LH
DØ DataExp. bkg Heavy flav.Higgs Signal
bΦ → bbb (3)D0 analysis (2.6 fb-1):
separation into 3/4/5-jet samples
flavour composition estimated using multiple b-tagging criteria
likelihood discriminant to improve S/B ratio
using topological information
obtain from double-tagged data, use to predict triple-tagged bkgd
8
D =Psig(�x)
Psig(�x) + Pbkg(�x)
]2 [GeV/cbbM50 100 150 200 250 300 350 400
-40
-20
0
20
40
]
2Pa
iring
s / [1
0 G
eV/c
100
200
300
400
500
600
700
100
200
300
400
500
600
700 -1DØ Prelim., L=1.61 fba) 3 jets exclusive
LHHigh-mass Y
DØ Data Exp. bkgHeavy flav.
]2 [GeV/cbbM50 100 150 200 250 300 350 400
-20-15-10
-505
101520
]
2Pa
iring
s / [1
0 G
eV/c
50100150200250300350400450
50100150200250300350400450 -1DØ Prelim., L=1.61 fb
b) 4 jets exclusiveLH
High-mass Y
DØ Data Exp. bkgHeavy flav.
]2 [GeV/cbbM50 100 150 200 250 300 350 400
-20-15-10
-505
101520
]
2Pa
iring
s / [1
0 G
eV/c
20
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100
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140
20
40
60
80
100
120
140 -1DØ Prelim., L=1.61 fbc) 5 jets exclusive
LHHigh-mass Y
DØ Data Exp. bkgHeavy flav.
bΦ → bbb (3)D0 analysis (2.6 fb-1):
separation into 3/4/5-jet samples
flavour composition estimated using multiple b-tagging criteria
likelihood discriminant to improve S/B ratio
using topological information
obtain from double-tagged data, use to predict triple-tagged bkgd
8
D =Psig(�x)
Psig(�x) + Pbkg(�x)
]2 [GeV/cAm80 100 120 140 160 180 200 220
tan
20
40
60
80
100
120
140
Excluded AreaExpected Limit
Excl
uded
at L
EP
-1DØ Preliminary, L=2.6 fb=-200 GeV ! max, hm
bgb
Φ → τ+τ-
Branching fraction only ~ 0.1, but much cleaner! ! can use this decay mode with gluon fusion channel
but need ≥ 1 leptonic decay: τμτhad, τeτhad, τeτμτ decays ! no sharp mass peak
substantial backgrounds: Z → τ+τ-, W+jets, multijets
9
t,b
Φ → τ+τ-
Branching fraction only ~ 0.1, but much cleaner! ! can use this decay mode with gluon fusion channel
but need ≥ 1 leptonic decay: τμτhad, τeτhad, τeτμτ decays ! no sharp mass peak
substantial backgrounds: Z → τ+τ-, W+jets, multijets
CDF published analysis (1.8 fb-1):
using “visible mass”
Z → τ+τ- from MC: energy scale
instrumental backgrounds:from initial looser τhad selection,known fake rate
9
t,b
0 50 100 150 200 250 300
mA = 140 GeV/c2
0.1
1
10
100
mvis (GeV/c2)
1
10
100
1000mA = 140 GeV/c2
e+τ, μ+τ
e+μ
Jet→τOther EWZ/γ*→ττφ→ττ
even
tsev
ents
(a)
(b)
m2vis = (pτ1 + pτ2 + /pT )2
/pT ≡ (/ET , /Ex , /Ey , 0)
Φ → τ+τ-
Branching fraction only ~ 0.1, but much cleaner! ! can use this decay mode with gluon fusion channel
but need ≥ 1 leptonic decay: τμτhad, τeτhad, τeτμτ decays ! no sharp mass peak
substantial backgrounds: Z → τ+τ-, W+jets, multijets
CDF published analysis (1.8 fb-1):
using “visible mass”
Z → τ+τ- from MC: energy scale
instrumental backgrounds:from initial looser τhad selection,known fake rate
9
t,b
m2vis = (pτ1 + pτ2 + /pT )2
/pT ≡ (/ET , /Ex , /Ey , 0)
small model dependence!
Φ → τ+τ- (2)D0: extended published analysis (1 fb-1) by 1.2 fb-1 (τμτhad)
Analysis similar to CDF (Z → τ+τ-, instrumental backgrounds)
optimised (NN) identification of τ→πντ, τ→ρντ, 3-prong decays
additional rejection against W (→ e/μ ν) + jets background (MT)
10
Visible Mass (GeV)20 40 60 80 100120140160180200220240
Even
ts
1
10
210
310
20 40 60 80 100120140160180200220240
1
10
210
310 DataZMultijetW + jets
tOther EW + t, 160 GeV
-1DØ, 1.0 fbh
!
Visible Mass (GeV)20 40 60 80 100120140160180200220240
Even
ts
1
10
210
310 (a)
Visible Mass (GeV)40 60 80 100 120 140 160 180 200 220 24040 60 80 100 120 140 160 180 200 220 240
DataZMultijetW + jets
tOther EW + t, 160 GeV
-1DØ, 1.0 fbhe
Visible Mass (GeV)40 60 80 100 120 140 160 180 200 220 240
(b)
Visible Mass (GeV)60 80 100 120 140 160 180 200 220 24060 80 100 120 140 160 180 200 220 240
DataZMultijetW + jets
tOther EW + t, 160 GeV
-1DØ, 1.0 fb!e
Visible Mass (GeV)60 80 100 120 140 160 180 200 220 240
(c)
Φ → τ+τ- (2)D0: extended published analysis (1 fb-1) by 1.2 fb-1 (τμτhad)
Analysis similar to CDF (Z → τ+τ-, instrumental backgrounds)
optimised (NN) identification of τ→πντ, τ→ρντ, 3-prong decays
additional rejection against W (→ e/μ ν) + jets background (MT)
10
) (GeV)vis
Visible Mass (M0 20 40 60 80 100 120 140 160 180 200 220 240
Even
ts
1
10
210
0 20 40 60 80 100 120 140 160 180 200 220 240
1
10
210
Multijet & W+jets
ttWW/WZ/ZZ
!!Z
Zdata
= 50 pb)=160GeV (M
) -1 Preliminary (1.2 fbD
Φ → τ+τ- (2)D0: extended published analysis (1 fb-1) by 1.2 fb-1 (τμτhad)
Analysis similar to CDF (Z → τ+τ-, instrumental backgrounds)
optimised (NN) identification of τ→πντ, τ→ρντ, 3-prong decays
additional rejection against W (→ e/μ ν) + jets background (MT)
10
(GeV)AM100 120 140 160 180 200 220 240
tan
0
10
20
30
40
50
60
70
80
90
100
Observed limitExpected limitLEP 2
100 120 140 160 180 200 220 2400
10
20
30
40
50
60
70
80
90
100-1DØ prel., 1-2.2 fb
= +200 GeV!, maxhm
(GeV)AM100 120 140 160 180 200 220 240
tan
0
10
20
30
40
50
60
70
80
90
100
Observed limitExpected limitLEP 2
100 120 140 160 180 200 220 2400
10
20
30
40
50
60
70
80
90
100-1DØ prel., 1-2.2 fb
= +200 GeV!No-mixing,
Limits generally (slightly) more restrictive than for bbb final state
bΦ → bτ+τ-
Small overlap with inclusive τ+τ- search, reduced Z → τ+τ-
background at low mΦ ! complementarity
D0 published analysis (2.7 fb-1, τμτhad):
dominant backgrounds: tt, multijet, Z+jets
estimate multijet background from same-sign events
enrich further using two (tt, multijet) multivariate discriminants
11
published
D0 0.2 0.4 0.6 0.8 1
Even
ts /
0.1
0
5
10
15
20
25 -1DØ, 2.7 fb
(a)
2=120 GeV/cM
DataZ+jetsMultijettt
OtherSignal
D0 0.2 0.4 0.6 0.8 1
Even
ts /
0.1
0
5
10
15
20
25
bΦ → bτ+τ-
Small overlap with inclusive τ+τ- search, reduced Z → τ+τ-
background at low mΦ ! complementarity
D0 published analysis (2.7 fb-1, τμτhad):
dominant backgrounds: tt, multijet, Z+jets
estimate multijet background from same-sign events
enrich further using two (tt, multijet) multivariate discriminants
11
published
)2 (GeV/cAM90 100 110 120 130 140 150 160 170 180
tan
0
20
40
60
80
100
90 100 110 120 130 140 150 160 170 1800
20
40
60
80
100
Observed limitExpected limitLEP
-1Ø, 0.3 fbD
-1Ø, 2.7 fbD
(c)
2 = -200 GeV/c! maxh m
)2 (GeV/cAM90 100 110 120 130 140 150 160 170 180
tan
0
20
40
60
80
100
90 100 110 120 130 140 150 160 170 1800
20
40
60
80
100
Observed limitExpected limitLEP
-1Ø, 0.3 fbD
-1Ø, 2.7 fbD
(b)
2 = -200 GeV/c! No-mixing
bΦ → bτ+τ-
Small overlap with inclusive τ+τ- search, reduced Z → τ+τ-
background at low mΦ ! complementarity
D0 published analysis (2.7 fb-1, τμτhad):
dominant backgrounds: tt, multijet, Z+jets
estimate multijet background from same-sign events
enrich further using two (tt, multijet) multivariate discriminants
11
published
)2 (GeV/cAM90 100 110 120 130 140 150 160 170 180
tan
0
20
40
60
80
100
90 100 110 120 130 140 150 160 170 1800
20
40
60
80
100
Observed limitExpected limitLEP
-1Ø, 0.3 fbD
-1Ø, 2.7 fbD
(a)
2 = +200 GeV/c! No-mixing
)2 (GeV/cAM90 100 110 120 130 140 150 160 170 180
tan
0
20
40
60
80
100
90 100 110 120 130 140 150 160 170 1800
20
40
60
80
100
Observed limitExpected limitLEP
-1Ø, 0.3 fbD
-1Ø, 2.7 fbD
(c)
2 = +200 GeV/c! maxh m
Combinations
Several channels with similar sensitivity ! combining results makes sense!
D0: combination of all neutral MSSM Higgs boson results
Tevatron: combination of τ+τ- results
12
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=-200 GeV " max, hm
-1DØ Preliminary, L= 1.0-2.6 fb
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=+200 GeV" max, hm
-1DØ Preliminary, L= 1.0-2.6 fb
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
NB: only 1.2 fb-1 of bττ data used
Combinations
Several channels with similar sensitivity ! combining results makes sense!
D0: combination of all neutral MSSM Higgs boson results
Tevatron: combination of τ+τ- results
12
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=-200 GeV "no mixing,
-1DØ Preliminary, L= 1.0-2.6 fb
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=+200 GeV"no mixing,
-1DØ Preliminary, L= 1.0-2.6 fb
]2 [GeV/cAm100 120 140 160 180 200 220
tan
20
40
60
80
100
NB: only 1.2 fb-1 of bττ data used
Combinations
Several channels with similar sensitivity ! combining results makes sense!
D0: combination of all neutral MSSM Higgs boson results
Tevatron: combination of τ+τ- results
12
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=-200 GeV " max, hm
-1Tevatron Run II Preliminary, L= 1.8-2.2 fb
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=+200 GeV" max, hm
-1Tevatron Run II Preliminary, L= 1.8-2.2 fb
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
Combinations
Several channels with similar sensitivity ! combining results makes sense!
D0: combination of all neutral MSSM Higgs boson results
Tevatron: combination of τ+τ- results
12
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=-200 GeV "no mixing,
-1Tevatron Run II Preliminary, L= 1.8-2.2 fb
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
Excluded by LEPObserved limitExpected limit
1 !Expected limit 2 !Expected limit
=+200 GeV"no mixing,
-1Tevatron Run II Preliminary, L= 1.8-2.2 fb
]2 [GeV/cAm100 120 140 160 180 200
tan
10
20
30
40
50
60
70
80
90
100
Charged Higgs Bosons
Focus on t → H+b decays (heavy H → tb out of Tevatron reach)
exploited in multiple ways to search for H → cs, τν decays in tt events
modified distribution of tt events over l+jets, l+l,and l+τhad final states
l = e, μpeak in l+jets di-jet invariantmass spectrum (H → cs)
13
)!tan(1 10
Bra
nchi
ng ra
tio
0
0.2
0.4
0.6
0.8
1=100 GeV+HM
decays to ±H"#scb*t
0h+W0A+W
b)+ H$BR(t
t
t̄b̄
b
H!
W
Charged Higgs Bosons: H→τνHigh tanβ: dominant decay mode
D0 analysis (0.9 fb-1) of l+τhad mode:
separate 3-jet, >3-jet channels
significant background from W+jets ! likelihood discriminant
Fix σ(tt) to SM value
14
published
Discriminant0 0.2 0.4 0.6 0.8 1
Even
ts /
0.05
0
10
20
30
40
50 (a)
Discriminant0 0.2 0.4 0.6 0.8 1
Even
ts /
0.05
0
10
20
30
40
50 -1DØ 0.9 fb
(B = 0)ttOther MCW+jetsMultijet
Discriminant0 0.2 0.4 0.6 0.8 1
Even
ts /
0.05
0
10
20
30
40
50 (b)
Discriminant0 0.2 0.4 0.6 0.8 1
Even
ts /
0.05
0
10
20
30
40
50 -1DØ 0.9 fb
(B = 0.5)ttOther MCW+jetsMultijet
B ≡ B(t →H+b)e + >3jets
(kinematic/topological variables)
(MH = 120 GeV)
Charged Higgs Bosons: H→τνHigh tanβ: dominant decay mode
D0 analysis (0.9 fb-1) of l+τhad mode:
separate 3-jet, >3-jet channels
significant background from W+jets ! likelihood discriminant
Fix σ(tt) to SM value
14
published
[GeV]!Hm80 100 120 140 160
b)+ H
Upp
er li
mit
on B
(t
00.05
0.10.15
0.20.25
0.30.35
0.40.45
0.5 1 sd!Expected
Observed
-1D0 0.9 fb
[GeV]!Hm80 100 120 140 160
b)+ H
Upp
er li
mit
on B
(t
00.05
0.10.15
0.20.25
0.30.35
0.40.45
0.5
[GeV]!Hm80 100 120 140 160 180
)ta
n(
20406080
100120140160180200220
-1D0 0.9 fbTheo
retica
lly In
acce
ssible
Expected
Observed
[GeV]!Hm80 100 120 140 160 180
)ta
n(
20406080
100120140160180200220
(kinematic/topological variables)
Method does not exploit depletion in other final states...
Charged Higgs Bosons: Combination
Better alternative: consider l+jets, l+l, l+τhad channels simultaneously
D0 analysis (1 fb-1):
follow earlier individual analyses, but use ε(MH)
allows for simultaneous fits of σ(tt) ! improvement for small MH!
Interpretation in various MSSM scenarios
15
published
MH = 80 GeV
l+jets 1 tag l+jets 2 tag dilepton +lepton
even
tN
10
210
310)=1 +B(H
Data b)=0.0+ H Br(t ttb)=0.3+ H Br(t ttb)=0.6+ H Br(t tt
background
-1DØ, L=1.0 fb
l+jets 1 tag l+jets 2 tag dilepton +lepton
even
tN
10
210
310)=1s c +B(H
Data b)=0.0+ H Br(t ttb)=0.3+ H Br(t ttb)=0.6+ H Br(t tt
background
-1DØ, L=1.0 fb
Charged Higgs Bosons: Combination
Better alternative: consider l+jets, l+l, l+τhad channels simultaneously
D0 analysis (1 fb-1):
follow earlier individual analyses, but use ε(MH)
allows for simultaneous fits of σ(tt) ! improvement for small MH!
Interpretation in various MSSM scenarios
15
published
Assuming B(H → τν) + B(H → cs) = 1
)s c+B(H0 0.2 0.4 0.6 0.8 1
b)
+ H
B(t
0
0.1
0.2
0.3
0.4
0.5
0.6Expected 95% CL limitObserved 95% CL limit
= 80 GeV+HM
-1DØ, L =1.0 fb
)s c+B(H0 0.2 0.4 0.6 0.8 1
b)
+ H
B(t
0
0.1
0.2
0.3
0.4
0.5
0.6
= 100 GeV+HM
-1DØ, L =1.0 fb
)s c+B(H0 0.2 0.4 0.6 0.8 1
b)
+ H
B(t
0
0.1
0.2
0.3
0.4
0.5
0.6
= 120 GeV+HM
-1DØ, L =1.0 fb
)s c+B(H0 0.2 0.4 0.6 0.8 1
b)
+ H
B(t
0
0.1
0.2
0.3
0.4
0.5
0.6
= 140 GeV+HM
-1DØ, L =1.0 fb
)s c+B(H0 0.2 0.4 0.6 0.8 1
b)
+ H
B(t
0
0.1
0.2
0.3
0.4
0.5
0.6
= 150 GeV+HM
-1DØ, L =1.0 fb
)s c+B(H0 0.2 0.4 0.6 0.8 1
b)
+ H
B(t
0
0.1
0.2
0.3
0.4
0.5
0.6
= 155 GeV+HM
-1DØ, L =1.0 fb
[GeV]+HM80 100 120 140 160
b)+ H
B(t
0
0.2
0.4
0.6
0.8
1
)=1 + +B(HExpected 95% CL limitObserved 95% CL limit
-1DØ, L=1.0 fb
Charged Higgs Bosons: Combination
Better alternative: consider l+jets, l+l, l+τhad channels simultaneously
D0 analysis (1 fb-1):
follow earlier individual analyses, but use ε(MH)
allows for simultaneous fits of σ(tt) ! improvement for small MH!
15
published
Charged Higgs Bosons: Combination
Better alternative: consider l+jets, l+l, l+τhad channels simultaneously
D0 analysis (1 fb-1):
follow earlier individual analyses, but use ε(MH)
allows for simultaneous fits of σ(tt) ! improvement for small MH!
Interpretation in various MSSM scenarios
15
published
[GeV] + HM80 90 100 110 120 130 140 150 160
tan
100
200 Theoretically inaccessibleExpected 95% CL limitExcluded 95% CL region
-1DØ, L = 1.0 fb-max scenariohm
[GeV] + HM80 90 100 110 120 130 140 150 160
tan
20
40
60
80
100
Theoretically inaccessibleExpected 95% CL limitExcluded 95% CL region
-1DØ, L =1.0 fb
no-mixing scenario
Charged Higgs Bosons: Combination
Better alternative: consider l+jets, l+l, l+τhad channels simultaneously
D0 analysis (1 fb-1):
follow earlier individual analyses, but use ε(MH)
allows for simultaneous fits of σ(tt) ! improvement for small MH!
Interpretation in various MSSM scenarios
15
published
[GeV]+HM80 90 100 110 120 130 140 150 160
tan
0.5
1
1.5
2
2.5
3)=1s c +B(H
Expected 95% CL limitExcluded 95% CL region
-1DØ, L =1.0 fb
Leptophobic Higgs: MSSM for low tanβ, Multi-Higgs Doublet models
Charged Higgs Bosons: Combination
Better alternative: consider l+jets, l+l, l+τhad channels simultaneously
D0 analysis (1 fb-1):
follow earlier individual analyses, but use ε(MH)
allows for simultaneous fits of σ(tt) ! improvement for small MH!
Interpretation in various MSSM scenarios
15
published
[GeV]+HM80 90 100 110 120 130 140 150 160
tan
10
20
30
40
50
60
Theoretically inaccessible) < 0.95 +) + B(Hs c +B(H
Expected 95% CL limitExcluded 95% CL region
-1DØ, L =1.0 fb
CPX scenariogh
CPXgh scenario: substantial H → cs fraction even for high 22 < tanβ < 55
Charged Higgs Bosons: H→csCDF analysis (2.2 fb-1) of double-tagged l+jets final states:
kinematic fit using mt, (leptonic) MW constraints
binned ML fit to non-b di-jet mass distribution
16
published
]2M(dijet) [GeV/c0 20 40 60 80 100 120 140 160 180
]2N
umbe
r of E
vent
s/[6
GeV
/c
0
5
10
15
20
25
30
35
40
0 20 40 60 80 100 120 140 160 1800
5
10
15
20
25
30
35
40Data
b) = 0.1+ HB(t
t in t+W bkgtnon-t
]2) [GeV/c+M(H60 80 100 120 140 160
) = 1
.0s
c +
b) w
ith B
(H+
HB
(t
0
0.1
0.2
0.3
0.4
0.5
0.6 Observed @ 95% C.L.Expected @ 95% C.L.68% of SM @ 95% C.L.95% of SM @ 95% C.L.
Overall tt counts not constrained ! reduced sensitivity at MH ≈MW
Possible in various (more exotic) SM extensions
Benchmark model: SM couplings to vector bosons, no couplings to fermions
D0 analysis (4.2 fb-1):
Vh and VBF production lumpedtogether (no “V” selection)
NN γ identification
Fermiophobic Higgs: H →γγ
17
update from 2.7 fb-1
q(′)q̄
V !
h
V V !
V !h
W
Possible in various (more exotic) SM extensions
Benchmark model: SM couplings to vector bosons, no couplings to fermions
D0 analysis (4.2 fb-1):
Vh and VBF production lumpedtogether (no “V” selection)
NN γ identification
cut on pT(γγ)
Fermiophobic Higgs: H →γγ
17
update from 2.7 fb-1
(GeV)T
p0 50 100 150 200 250 300 350 400
Even
ts/5
GeV
-410
-310
-210
-110
1
data=110GeV)
fhVH (M
=110GeV)fh
VBF (M
preliminary-1DØ, 4.2 fb
q(′)q̄
V !
h
V V !
V !h
W
Possible in various (more exotic) SM extensions
Benchmark model: SM couplings to vector bosons, no couplings to fermions
D0 analysis (4.2 fb-1):
Vh and VBF production lumpedtogether (no “V” selection)
NN γ identification
cut on pT(γγ)
jj/γj identified usingknown fake rates
fit signal in 20 GeVmass window
Fermiophobic Higgs: H →γγ
17
update from 2.7 fb-1
q(′)q̄
V !
h
V V !
V !h
W
(GeV)M60 80 100 120 140 160 180
Even
ts/5
GeV
0
20
40
60
80
100
120
140
60 80 100 120 140 160 1800
20
40
60
80
100
120
140
datadirect
+jjj*->eeZ/
preliminary-1DØ, 4.2 fb
Possible in various (more exotic) SM extensions
Benchmark model: SM couplings to vector bosons, no couplings to fermions
D0 analysis (4.2 fb-1):
Vh and VBF production lumpedtogether (no “V” selection)
NN γ identification
cut on pT(γγ)
jj/γj identified usingknown fake rates
fit signal in 20 GeVmass window
(GeV)fhM
80 90 100 110 120 130 140 150
) (fb
) B
R(!
1
10
210
Observed LimitExpected LimitNLO prediction
1 "Expected Limit 2 "Expected Limit
preliminary-1DØ, 4.2 fb
(GeV)fhM
80 90 100 110 120 130 140 150
)BR
(
-310
-210
-110
1
Observed LimitExpected LimitNLO prediction
1 !Expected Limit 2 !Expected Limit
-1DØ, 1.1 fbLEP
preliminary-1DØ, 4.2 fb
Fermiophobic Higgs: H →γγ
17
update from 2.7 fb-1
q(′)q̄
V !
h
V V !
V !h
W
Fermiophobic Higgs: H →γγ
)2c (GeV/m0 100 200 300 400 500
2 cEn
trie
s/2
GeV
/
0
2
4
6
8
10
)2c (GeV/m0 100 200 300 400 500
2 cEn
trie
s/2
GeV
/
0
2
4
6
8
10
Central-Central
)2c (GeV/m0 50 100 150
)2 cA
rbitr
ary
/ 2 (G
eV/
SignalSimulation
)2c (GeV/m0 100 200 300 400 500
2 cEn
trie
s/2
GeV
/
0
2
4
6
8
10
12
)2c (GeV/m0 100 200 300 400 500
2 cEn
trie
s/2
GeV
/
0
2
4
6
8
10
12
Central-Plug
)2c (GeV/m0 50 100 150
)2 cA
rbitr
ary
/ 2 (G
eV/
SignalSimulation
(a)
(b)
Possible in various (more exotic) SM extensions
Benchmark model: SM couplings to vector bosons, no couplings to fermions
CDF analysis (3 fb-1):
Vh and VBF production lumpedtogether (as in D0 analysis)
pT(γγ) > 75 GeV
fit with 10 GeVsignal mass window
18
published
q(′)q̄
V !
h
V V !
V !h
W
Fermiophobic Higgs: H →γγPossible in various (more exotic) SM extensions
Benchmark model: SM couplings to vector bosons, no couplings to fermions
CDF analysis (3 fb-1):
Vh and VBF production lumpedtogether (as in D0 analysis)
pT(γγ) > 75 GeV
fit with 10 GeVsignal mass window
18
published
q(′)q̄
V !
h
V V !
V !h
W
)2c (GeV/hm70 80 90 100 110 120 130 140
)
h(
B
-310
-210
-110
1
)-1CDF limit (3.0 fbExpected limit1 sigma region2 sigma regionBenchmark predictionLEP limit
)2c (GeV/hm70 80 90 100 110 120 130 140
)
h(
B
-310
-210
-110
1
Four Fermion GenerationsStraightforward SM extension
evade Nν=3 constraint by heavy νenhanced gg→H cross section (factor 7.5 - 9)
Tevatron combined analysis (CDF 4.8 fb-1, D0 5.4 fb-1) adjusting corresponding SM H → W+W- search:
correct signal acceptance for different VH, VBF admixtures
19
t,b′, t′
submitted
-60-40-20
020406080
100
-2 -1.8 -1.6 -1.4 -1.2 -1 -0.8 -0.6 -0.4 -0.2 0log10(s/b)
Even
ts/0
.2 CDF+D0 Run II PreliminaryL=4.8 - 5.4 fb-1
mH=200 GeV
Data-BackgroundSignal±1 s.d. on Background
10-3
10-2
10-1
1
10
10 2
10 3
10 4
10 5
-2 -1.5 -1 -0.5 0 0.5 1log10(s/b)
Even
ts/0
.2 DataBackgroundSignal
CDF+D0 Run II PreliminaryL=4.8-5.4 fb-1
mH=200 GeV
Four Fermion GenerationsStraightforward SM extension
evade Nν=3 constraint by heavy νenhanced gg→H cross section (factor 7.5 - 9)
Tevatron combined analysis (CDF 4.8 fb-1, D0 5.4 fb-1) adjusting corresponding SM H → W+W- search:
correct signal acceptance for different VH, VBF admixtures
H → W+W- branching fraction affected by decays to heavy fermions ! 2 scenarios (both: mb´, mt´ ~ 400 - 500 GeV):
ml = 100 GeV, mν = 80 GeV
ml = mν = 1 TeV
19
t,b′, t′
submitted
Four Fermion GenerationsStraightforward SM extension
evade Nν=3 constraint by heavy νenhanced gg→H cross section (factor 7.5 - 9)
Tevatron combined analysis (CDF 4.8 fb-1, D0 5.4 fb-1) adjusting corresponding SM H → W+W- search:
correct signal acceptance for different VH, VBF admixtures
H → W+W- branching fraction affected by decays to heavy fermions ! 2 scenarios (both: mb´, mt´ ~ 400 - 500 GeV):
ml = 100 GeV, mν = 80 GeV
ml = mν = 1 TeV
19
t,b′, t′
submitted
0
1
2
3
4
120 140 160 180 200 220 240 2600
1
2
3
4
mH(GeV)
(gg
H)!
Br(H
WW
) (pb
)
CDF+D0 Run II PreliminaryL=4.8 - 5.4 fb-1
Expected 95% C.L. Limit
Observed 95% C.L. Limit
"1 s.d. Expected Limit
"2 s.d. Expected Limit
4G (infinite-mass)
4G (low-mass) Significantly increased exclusion regionlow mass: 131 GeV < MH < 204 GeVhigh mass: 131 GeV < MH < 208 GeV
NMSSM Higgs PhenomenologyNMSSM: adds one gauge singlet superfield
preserves ρ=1
SSB: replaces μ (MSSM) with dimensionless coupling constant
Higgs sector:
additional CP-odd (a) and CP-even (h) Higgs boson
Allows for Higgs loophole at LEP:
SM-like h (within LEP kinematic reach), decaying mostly as h → aa
Ma < 2mb: a → ττ, gg, cc ! only looked for by OPAL in MSSM context
limited to mh < 86 GeV
20
NMSSM: Charged Higgs BosonCDF analysis (2.7 fb-1): search in l+jets sample(regular tt event w/ extra τ+τ- pair)
soft τ’s ! identify through add’l isolated track
backgrounds:
underlying event (universal pT spectrum, check in l+1/2jet events)
Z/γ∗+jets (1 lepton missed or from τ decay)
21
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
210
310
410
510
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
210
310
410
510Data
*+Jet!Z/
Top and Diboson
Underlying Event
measurementll"*!0.03 times Z/± of 1.00*!Z/#Fit
Pre-Tag Lepton + 1 Jet Events
-1CDF Run II Preliminary, L=2.7fb
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
10
210
310
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
10
210
310
Data*+Jets!Z/
Top and Diboson
Underlying Event
measurementll"*!0.07 times Z/± of 1.03*!Z/#Fit
Pre-Tag Lepton + 2 Jet Events
-1CDF Run II Preliminary, L=2.7fb
new
NMSSM: Charged Higgs BosonCDF analysis (2.7 fb-1): search in l+jets sample(regular tt event w/ extra τ+τ- pair)
soft τ’s ! identify through add’l isolated track
backgrounds:
underlying event (universal pT spectrum, check in l+1/2jet events)
Z/γ∗+jets (1 lepton missed or from τ decay)
21
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
0
10
20
30
40
50
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
0
10
20
30
40
50Data
2)=90, m(A)=9 GeV/c±Signal, m(H
SM Boson Daughter Tracks
Underlying Event
-1CDF Run II Preliminary, L=2.7fb
)=1!!"BR(Ab)=0.11±H"BR(t
A)=1±W"±BR(H
Fit as function of both ma and MH
UE normalisation inferred from b-tagged 3-jet datasignal shown at exclusion level
new
NMSSM: Charged Higgs BosonCDF analysis (2.7 fb-1): search in l+jets sample(regular tt event w/ extra τ+τ- pair)
soft τ’s ! identify through add’l isolated track
backgrounds:
underlying event (universal pT spectrum, check in l+1/2jet events)
Z/γ∗+jets (1 lepton missed or from τ decay)
21
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
0
10
20
30
40
50
(GeV/c)T
Lead Track p4 6 8 10 12 14 16 18 20
Even
ts P
er G
eV/c
0
10
20
30
40
50 Data
2)=140, m(A)=7 GeV/c±Signal, m(H
SM Boson Daughter Tracks
Underlying Event
-1CDF Run II Preliminary, L=2.7fb
)=1!!"BR(Ab)=0.19±H"BR(t
A)=1±W"±BR(H
Fit as function of both ma and MH
UE normalisation inferred from b-tagged 3-jet datasignal shown at exclusion level
new
NMSSM: Charged Higgs BosonCDF analysis (2.7 fb-1): search in l+jets sample(regular tt event w/ extra τ+τ- pair)
soft τ’s ! identify through add’l isolated track
backgrounds:
underlying event (universal pT spectrum, check in l+1/2jet events)
Z/γ∗+jets (1 lepton missed or from τ decay)
21
)2 mass (GeV/c±H90 100 110 120 130 140 150 160
b)± H
!BR
(t
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
-1CDF Run II Preliminary, L=2.7fb
Ab±W!b±H!95% CL Exclusion for t)=1""!BR(A )=1""!BR(A
A)=1±W!±BR(H 2m(A)=4 GeV/c Expected Observed 2m(A)=7 GeV/c Expected Observed 2m(A)=8 GeV/c Expected Observed 2m(A)=9 GeV/c Expected Observed
new
NMSSM: Neutral Higgs Boson
D0 analysis (4.2 fb-1): search for gg → h → aa, with a → μ+μ-/τ+τ- in inclusive dimuon events (pT > 10 GeV)
2mμ < ma < 2mτ: muons too collinear to be reconstructed separately ! association with track (R < 1) only (NB: BF uncertain)
22
published
,track) (GeV)µ(1m0 0.5 1 1.5 2 2.5 3 3.5
,trac
k) (G
eV)
µ( 2m
0
0.5
1
1.5
2
2.5
3
3.5 -1, 4.2 fbOD
=3 GeVaM=1 GeVaM=.5 GeVaM=.2143 GeVaM
Data
(b)
tight (μ+track) isolation criteriaefficiency for collinear tracks from KS
σ(pp̄ → h + X ) · B(h → aa) · B(a → µ+µ−)2 < 10 fb
NMSSM: Neutral Higgs Boson
D0 analysis (4.2 fb-1): search for gg → h → aa, with a → μ+μ-/τ+τ- in inclusive dimuon events (pT > 10 GeV)
2mμ < ma < 2mτ: muons too collinear to be reconstructed separately ! association with track (R < 1) only (NB: BF uncertain)
ma > 2mτ (μ+μ-τ+τ-): reconstruct a → μ+μ- candidates explicitly
use of muons ! low efficiency
22
published
Dimuon mass (GeV)0 2 4 6 8 10 12 14 16 18 20
Even
ts /
0.1
GeV
00.20.40.60.8
11.21.41.61.8
2 -1, 4.2 fbODDataBackgroundSignals
collimated τ not individually identified: ET / μ / ebackground estimated from low-ET region
/
/
NMSSM: Neutral Higgs Boson
D0 analysis (4.2 fb-1): search for gg → h → aa, with a → μ+μ-/τ+τ- in inclusive dimuon events (pT > 10 GeV)
2mμ < ma < 2mτ: muons too collinear to be reconstructed separately ! association with track (R < 1) only (NB: BF uncertain)
ma > 2mτ (μ+μ-τ+τ-): reconstruct a → μ+μ- candidates explicitly
use of muons ! low efficiency
22
published
(GeV)aM4 6 8 10 12 14 16 18
aa) (
pb)
BR(
h!
h)
p(p
0123456789
10Observed limitExpected limitTheory
-1, 4.2 fbOD
(a)
(GeV)hM80 100 120 140 160 180 200
aa) (
pb)
BR(
h!
h)
p(p
0123456789
10
Observed limitExpected limitTheory
-1, 4.2 fbOD (b)
mh = 100 GeV ma = 4 GeV
Not DiscussedFermiophobic Higgs boson searches
CDF W±h → W±W+W- (2.7 fb-1)
D0 hhW± → γγγγW± (0.8 fb-1)
Doubly charged Higgs boson searches
D0 H++H-- → μ+μ+μ-μ- (1.1 fb-1)
CDF H++H-- → l+τ+l-τ- (0.3 fb-1)
23
Conclusion & Outlook
Consolidation in mainstream MSSM analyses
First MSSM combinations have been performed
Analyses with significantly larger datasets are underway
In the near future, the Tevatron will likely continue to play an important role in BSM Higgs physics
24