Finding the Higgs · Finding the Higgs Robert Harlander Institute for Theoretical Particle Physics University of Karlsruhe YETI’05, January 5–8, 2005 Robert Harlander — Finding

Finding the Higgs

Robert Harlander

Institute for Theoretical Particle Physics

University of Karlsruhe

YETI’05, January 5–8, 2005

Robert Harlander — Finding the Higgs – p. 1

http://www.robert-harlander.de/

Guidelines

What are we looking for?

Higgs properties (Standard Model):

spin = 0

electric charge = 0

mass = ?

couples to mass!

H

t

p

X

X

g

p

=mt

v,

H= 2

M2V

v


Guidelines

What are we looking for?(. . . of course, anything new will make us happy. . . )


spin = 0

electric charge = 0

mass = ?

couples to mass!

H

t

p

X

X

g

p

=mt

v,

H= 2

M2V

v


Guidelines



spin = 0

electric charge = 0

mass = ?

couples to mass!

H

t

p

X

X

g

p

=mt

v,

H= 2

M2V

v


Guidelines



spin = 0

electric charge = 0

mass = ?

couples to mass!

H

t

p

X

X

g

p

=mt

v,

H= 2

M2V

v


Particle masses

t b c s τ µ e Z W± H

178 5 1.3 0.1 1.8 0.1 0.0005 91 80 . 250

≥ 115


Higgs search at LEP

direct:

Z(M = 91 GeV)

)E ~ 205 GeV( ~

Ze

He

+

_

Z*

⇒ MH = 114+69

−45 GeVMH < 260 GeV


Higgs search at LEP

direct:

Z(M = 91 GeV)

)E ~ 205 GeV( ~

Ze

He

+

_

Z*

⇒ MH & 114.4 GeV

⇒

MH = 114+69

−45 GeV

MH < 260 GeV


Higgs search at LEP

direct:

Z(M = 91 GeV)

)E ~ 205 GeV( ~

Ze

He

+

_

Z*

⇒ MH & 114.4 GeV

indirect: H+

e µ

_Z

+

_

e µ

0

1

2

3

4

5

6

10020 400

mH [GeV]

∆χ2

Excluded Preliminary

∆αhad =∆α(5)

0.02761±0.00036

0.02749±0.00012

incl. low Q2 data

Theory uncertainty

⇒ MH = 114+69

−45 GeV

MH < 260 GeV


Higgs search at LEP

direct:

Z(M = 91 GeV)

)E ~ 205 GeV( ~

Ze

He

+

_

Z*

⇒ MH & 114.4 GeV

indirect: H+

e µ

_Z

+

_

e µ

0

1

2

3

4

5

6

10020 400

mH [GeV]

∆χ2


∆αhad =∆α(5)

0.02761±0.00036

0.02749±0.00012

incl. low Q2 data

Theory uncertainty

⇒ MH = 114+69

−45 GeV

MH < 260 GeV


Higgs search at LEP

direct:

Z(M = 91 GeV)

)E ~ 205 GeV( ~

Ze

He

+

_

Z*

⇒ MH & 114.4 GeV

indirect: H+

e µ

_Z

+

_

e µ

0

1

2

3

4

5

6

10020 400

mH [GeV]

∆χ2


∆αhad =∆α(5)

0.02761±0.00036

0.02749±0.00012

incl. low Q2 data

Theory uncertainty

⇒ MH = 114+69

−45 GeV

MH < 260 GeV


Particle masses


178 5 1.3 0.1 1.8 0.1 0.0005 91 80 . 250

≥ 115


Particle masses


178 5 1.3 0.1 1.8 0.1 0.0005 91 80 . 260

≥ 114


Higgs Decay

b

b

HW

W

γ

γ

H

Z

HZ

ν

ν

W

W

l

H

_l

+


Higgs Decay

b

b

HW

W

γ

γ

H

l+

l_

_

+l

l

Z

HZ

ν

ν

W

W

l

H

_l

+


Higgs Decay

b

b

HW

W

γ

γ

H

q

q

_

+l

l

Z

HZ

ν

ν

W

W

l

H

_l

+


Higgs Decay

b

b

HW

W

γ

γ

H

ν

ν

W

W

l

H

_l

+


Higgs Decay

b

b

H

W

W

γ

γ

H

ν

ν

W

W

l

H

_l

+


Higgs Decay

b

b

HW

W

γ

γ

H

ν

ν

W

W

l

H

_l

+


Tevatron Discovery Potential


Tevatron Discovery Potential

currently:


Higgs search at the LHC

proton – proton collider









H

t

p

X

X

g

p

gluon fusion ttH



H

tg

gluon fusion ttH



X

X

H

t

p

g

p

gluon fusion

ttH



X

X

H

t

p

g

p

H

t

p

X

X

g

p

gluon fusion

ttH



X

X

H

t

p

g

p

H

tg

gluon fusion

ttH



X

X

H

t

p

g

p p

p

X

H

X

gt

gluon fusion ttH



H

tg

H

tg

gluon fusion ttH



H



q

q

H



X

H

pq

pq

X

VBF



X

H

pq

pq

X

V

H

VBF



X

H

pq

pq

X

Vq

qH

VBF



X

H

pq

pq

X

q

q V

H

X

p

p

X

VBF Higgs Strahlung



q

q

H

Vq

qH

VBF Higgs Strahlung


Diffractive Higgs Production

X

X

H

t

p

g

p



tp

p

X

X

H

g



p

p

pt

p

H

g



p

p

pt

p

H

g

signature: p ⊕ H ⊕ p (⊕ = rapidity gap)[Khoze, Martin, Ryskin][Boonekamp, de Roeck, Peschanski, Royon], . . .


Gluon Fusion vs. ttH

H

tg

H

tg

gluon fusion ttH



H

tg

H

tg

gluon fusion ttH

s ≥ MH s ≥ 2mt + MH



H

tg

H

tg

gluon fusion ttH


s = x1 x2s ∼ x2 s



H

tg

H

tg

gluon fusion ttH


x ≥ 0.8 · 10−2 x ≥ 3.3 · 10−2

s = x1 x2s ∼ x2 s


Cross sections

σ(pp → H + X) [pb]√s = 14 TeV

NLO / NNLO

MRST

gg → H (NNLO)

qq → Hqqqq

_' → HW

qq_ → HZ

gg/qq_ → tt

_H

MH [GeV]

10-4

10-3

10-2

10-1

1

10

10 2

100 200 300 400 500 600 700 800 900 1000

tt

t

H

H

q

q

Vq

V

q

t

_t

H

q

q H

V_

V


Cross sections

σ(pp → H + X) [pb]√s = 14 TeV

NLO / NNLO

MRST

gg → H (NNLO)

qq → Hqqqq

_' → HW

qq_ → HZ

gg/qq_ → tt

_H (NLO)

MH [GeV]

10-4

10-3

10-2

10-1

1

10

10 2

100 200 300 400 500 600 700 800 900 1000

tt

t

H

H

q

q

Vq

V

q

t

_t

H

q

q H

V_

V


Cross sections

σ(pp → H + X) [pb]√s = 14 TeV

NLO / NNLO

MRST

gg → H (NNLO)

qq → Hqqqq

_' → HW

qq_ → HZ

gg/qq_ → tt

_H (NLO)

MH [GeV]

10-4

10-3

10-2

10-1

1

10

10 2

100 200 300 400 500 600 700 800 900 1000

tt

t

H

H

q

q

Vq

V

q

t

_t

H

q

q H

V_

V


Cross sections

σ(pp → H + X) [pb]√s = 14 TeV

NLO / NNLO

MRST

gg → H (NNLO)

qq → Hqqqq

_' → HW

qq_ → HZ

gg/qq_ → tt

_H (NLO)

MH [GeV]

10-4

10-3

10-2

10-1

1

10

10 2

100 200 300 400 500 600 700 800 900 1000

tt

t

H

H

q

q

Vq

V

q

t

_t

H

q

q H

V_

V


Gluon fusion: tt

t

H

largest cross section

gg → H → ZZ → 4µ: gold plated mode for MH & 135 GeV

Z

Z

_µ

+µ

+µ_

µ

t

H

X

p

X

g

p

sensitive to

new particles, e.g. supersymmetry: tt

t

H +~t

~

t~ H

t

top Yukawa coupling


Gluon fusion: tt

t

H



Z

Z

_µ

+µ

+µ_

µ

t

H

X

p

X

g

p

sensitive to


t

H +~t

~

t~ H

t

top Yukawa coupling


Gluon fusion: tt

t

H



Z

Z

_µ

+µ

+µ_

µ

t

H

X

p

X

g

p

sensitive to


t

H +~t

~

t~ H

t

top Yukawa coupling


Gluon fusion: tt

t

H

but:

gg → H → bb not useful!


Gluon fusion: tt

t

H

but: gg → H → bb not useful!


Gluon fusion: tt

t

H


particle mass (GeV)

σ rate ev/yearLHC √s=14TeV L=1034cm-2s-1

barn

mb

µb

nb

pb

fb

50 100 200 500 1000 2000 5000

GHz

MHz

kHz

Hz

mHz

µHz

1

10

10 2

10 3

10 4

10 5

10 6

10 7

10 8

10 9

10 10

10 11

10 12

10 13

10 14

10 15

10 16

10 17

LV1 input

max LV2 inputmax LV1 output

max LV2 output

σ inelastic

bb–

tt–

W

W→lνZ

Z→l+l-

ZSM→3γ

gg→HSM

qq–

→qq–HSM

HSM→ZZ(*)→4l

HSM→γγh→γγ

tanβ=2-50ZARL→l+l-

Zη→l+l-scalar LQ

SUSY q~q~+q

~g~+g

~g~

tanβ=2, µ=mg~=mq

~

tanβ=2, µ=mg~=mq

~/2


Gluon fusion: tt

t

H


need to rely on gg → H → γγ at MH . 135 GeV


Gluon fusion: tt

t

H



CER

N L

HC

Higgs physics

Some extensions of the Standard

Model involve a richer set of Higgs

bosons: in the Minimal

Supersymmetric SM there are five

new bosons (h0, H

0, A

0, H

+, H

-).

Their discovery involves the use of

more complicated signatures, such

as the identification of a jet as

coming from b quarks

Observability of the SM Higgs in CMS with 10

5 pb

-1. The CMS

detector can probe the entire mass range up to MH ~ 1 TeV with a signal significance well above 5σ

4. For the highest MH, in the range 0.5 - 1 TeV, the promising channels for 105 pb-1 are H0 → ZZ → �

+�–

νν, H0 → ZZ → �+�–

jj and H0 → W+W

– → �±νjj.

Detection relies on leptons, jets and missing transverse energy (Et

miss), for which the hadronic calorimeter( HCAL ) performance is very important

2-3. In the MH range 130 - 700 GeV the most promising channel is H0 → ZZ*→ 2�+2�

– or H0 → ZZ → 2�+2�–. The detection relies on the

excellent performance from the muon chambers, the tracker and the electromagnetic calorimeter. For MH ≤ 170 GeV a mass resolution of ~1 GeV should be achieved with the 4 Tesla magnetic field and the high resolution of the crystal calorimeter

10060

5

10

15

20

25

200 400 700

MH (GeV)

Sig

nific

an

ce

Standard Model Higgs

γγ

γγ + ≥ 2 jets

S= NS

NB

S= NS

NB

S= NS

NS + NB

H → ZZ, ZZ* → 4 ±

H → WW →

γγ

ν ν

H → ZZ → ν ν

40

35

30

Ne

ν/1

00 fb

–1/ 5

GeV

70

60

50

40

30

20

10

00 50

104.05

100 150 200 250

SM

M (bb), GeV

h → bb in mSUGRA

1. H0 → γγ is the most promising channel if MH is in the range 80 – 140 GeV. The high performance PbWO4 crystal electromagnetic calorimeter in CMS has been optimized for this search. The γγ mass resolution at Mγγ ~ 100 GeV is better than 1%, resulting in a S/B of ≈1/20. With larger data samples (≥ 105 pb-1) the "associated" modes (pp → WH0 and pp → ttH0) should give higher S/B ratios for the same H0 decay channel

8000

6000

4000

2000

080 100 120 140

Mγγ (GeV)

Higgs signal

Eve

nts

/ 5

00 M

eV

fo

r 10

5 p

b-1

H → γγ

MH ≤ 130 GeV

60

80

20

40

0100 120 140 160 180 200

M (4 ±) GeV

Eve

nts

/ 2

Ge

V f

or

Lin

t =

10

5 p

b-1

tt + Zbb + ZZ*

Et > 20,15,10,10 GeV;

pt > 20,10,5,5 GeV;µ

|ηe, | < 2.5, 2.4;µ

e

H → ZZ*→ 4 ±

130 ≤ MH ≤ 170 GeV 5

4

3

2

1

0 200 400 600 800 1000 1200 1400 1600 1800

H → ZZ → ��jjM

H= 800 GeV

M(��jj), GeV

Ne

v /

20

0G

eV

/ 3

*10

4 p

b-1

Signal

Bkgd

CENTRAL CUTS (Iη < 2.4):

Pl> 50 GeV/c Pz> 150 GeV/c

TAGGING JETS(IηI > 2.4):

1 cluster, No addit. jets with Pt > 40 GeV

I Mcl

- MZ

I < 15 GeVI Mll - M

Z I < 10 GeV

tt

I

2 jets with E > 400 GeV and Pt > 10GeV/c

The Standard Model (SM) of Particle Physics has unified the Electromagne-tic interaction (carrier: γ) and the weak interaction (carriers: W+, W–, Z0). Yet these four bosons are very different: the γ is massless whereas the W± and Z0

are quite massive (80 – 90 GeV). In the framework of the SM particles acquire mass through their interaction with the Higgs field. This implies the existence of a new particle: the Higgs boson H0. The theory does not predict the mass of the H0, but it does predict its production rate and decay modes for each possible mass. CMS has been optimized to discover the Higgs in the full expected mass range 0.08 TeV < MH < 1 TeV~ ~

The decay signature of the Higgs depends on its mass:

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+ ++

+

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+

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+

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+

+

+

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+++++++

+

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++++

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421 H(800 GeV) →e+e- jet jet→ZZZZ*H(130 GeV) → e+e- e+e-→ 3 H(150 GeV) → µ+µ- µ+µ-→ZZ*H(100 GeV) → γ γ


Gluon fusion: tt

t

H



phase space is a single point: s ≡ M2H


Gluon fusion: tt

t

H




NLO:Ht

t

t

⇒ phase space opens: s ≥ M2H

!


Gluon fusion: tt

t

H




NLO:Ht

t

t


!

⇒ large radiative corrections expected


Gluon fusion: tt

t

H




NLO:Ht

t

t


!

⇒ large radiative corrections expected→ reliable result requires NNLO


Gluon fusion: theory prediction

tt

t

H

1

10

100 120 140 160 180 200 220 240 260 280 300

σ(pp→H+X) [pb]

MH [GeV]

LO

√s = 14 TeV

[R.H., Kilgore ’02][Anastasiou, Melnikov ’02][Ravindran, Smith,

v. Neerven ’03]

[Spira, Djouadi, Graudenz,Zerwas ’91/’93]

[Dawson ’91]



tH

t

1

10

100 120 140 160 180 200 220 240 260 280 300

σ(pp→H+X) [pb]

MH [GeV]

LONLO

√s = 14 TeV


v. Neerven ’03]


[Dawson ’91]



tH

t

1

10

100 120 140 160 180 200 220 240 260 280 300

σ(pp→H+X) [pb]

MH [GeV]

LONLONNLO

√s = 14 TeV


v. Neerven ’03]


[Dawson ’91]


Resummation

[Catani, de Florian,Grazzini, Nason (’03)]


ttH

t

_t

H

clear signature: bbbbW+W−

[Beenakker, Dittmaier, Krämer,Plümper, Spira, Zerwas ’01]

[Dawson, Reina, Wackeroth,Orr, Jackson ’01-’03]


ttH

t

_t

H


direct handle on top Yukawa coupling




ttH

t

_t

H



but: rather small cross section




ttH

t

_t

H



but: rather small cross section

increased by QCD corrections?




ttH

t

_t

H

σ(pp → tt_ H + X) [fb]

√s = 14 TeV

MH = 120 GeV

µ0 = mt + MH/2

NLO

LO

µ/µ0

0.2 0.5 1 2 50

200

400

600

800

1000

1200

1400

1




ttH

t

_t

H

σ(pp → tt_ H + X) [fb]

√s = 14 TeV

MH = 120 GeV

µ0 = mt + MH/2

NLO

LO

µ/µ0

0.2 0.5 1 2 50

200

400

600

800

1000

1200

1400

1




Vector Boson Fusion

H

q

q

Vq

V

q

signature: two forward jets + HiggsH → γγ, H → τ+τ−, H → WW , H → bb


Vector Boson Fusion

H

q

q

Vq

V

q


important for discovery ([Rainwater, Zeppenfeld ’97], . . . )and study (e.g. couplings [Zeppenfeld et al.], [Dührssen et al.])


Vector Boson Fusion

H

q

q

Vq

V

q


important for discovery ([Rainwater, Zeppenfeld ’97], . . . )and study (e.g. couplings [Zeppenfeld et al.], [Dührssen et al.])

QCD corrections under control (and small)[Han, Willenbrock ’91], [Figy, Oleari, Zeppenfeld ’03]


Higgs Strahlung

q

q H

V_

V


Higgs Strahlung

q

q H

V_

V

most important mode at Tevatron!


Higgs Strahlung

q

q H

V_

V

most important mode at Tevatron!

. . . but only marginal importance at LHC


Higgs Strahlung

H

V

V

_q

q

0.9

0.95

1

1.05

1.1

1.15

1.2

1.25

1.3

1.35

80 100 120 140 160 180 200MH[GeV]

KW

H(L

HC

)

LO

NLO

[Brein, Djouadi, R.H. ’03]

[Han, Willenbrock ’90]

[Ciccolini, Dittmaier, Krämer ’03]


Higgs Strahlung

q

q H

V_

V

0.9

0.95

1

1.05

1.1

1.15

1.2

1.25

1.3

1.35

80 100 120 140 160 180 200MH[GeV]

KW

H(L

HC

)

LO

NLO

NNLO[Brein, Djouadi, R.H. ’03]




Higgs Strahlung

q

q H

V_

V

0.9

0.95

1

1.05

1.1

1.15

1.2

1.25

1.3

1.35

80 100 120 140 160 180 200MH[GeV]

KW

H(L

HC

)

QCD+EW

LO

NLO

NNLO[Brein, Djouadi, R.H. ’03]




Discovery Potential

1

10

10 2

100 120 140 160 180 200

mH (GeV)

Sig

nal s

igni

fica

nce

H → γ γ ttH (H → bb) H → ZZ(*) → 4 l H → WW(*) → lνlν qqH → qq WW(*)

qqH → qq ττ

Total significance

5 σ

∫ L dt = 30 fb-1

(no K-factors)

ATLAS


Higgs sector in SUSY

H ↔ h0, H0, A, H+, H−

Mh0 . 130 GeV

modified couplings to SM particles (tan β!)

implications for Higgs production:

tt

t

H +~t

~

t~ H

t

t

_t

H + h

b

_b



H ↔ h0, H0, A, H+, H−

Mh0 . 130 GeV



tt

t

H

+~t

~

t~ H

t

t

_t

H

+ h

b

_b



H ↔ h0, H0, A, H+, H−

Mh0 . 130 GeV



tt

t

H +~t

~

t~ H

t

t

_t

H

+ h

b

_b



H ↔ h0, H0, A, H+, H−

Mh0 . 130 GeV



tt

t

H +~t

~

t~ H

t

t

_t

H + h

b

_b


Example: “gluophobic Higgs”

[Djouadi ’98], [Carena et al. ’99]

tt

t

H +~t

~

t~ H

t

interfere destructively!

[R.H., Steinhauser ’04]

mt1= 200 GeV

mg = 1 TeV

tan β = 10 , α = 0 ,

θt =π

4

0

20

40

60

80

100

300 400 500 600 700 800 900

σ(pp→h+X) [pb]

m [GeV]t2~

SUSY, LO

SM, LO

LHC




tt

t

H +~t

~

t~ H

t

+t

~H

t


mt1= 200 GeV

mg = 1 TeV

tan β = 10 , α = 0 ,

θt =π

4

0

20

40

60

80

100

300 400 500 600 700 800 900

σ(pp→h+X) [pb]

m [GeV]t2~

SUSY, LO

SM, LO

LHC




tt

t

H +~t

~

t~ H

t

+t

~H

t


mt1= 200 GeV

mg = 1 TeV

tan β = 10 , α = 0 ,

θt =π

4

0

20

40

60

80

100

300 400 500 600 700 800 900

σ(pp→h+X) [pb]

m [GeV]t2~

SUSY, NNLO’SUSY, NLOSUSY, LO

SM, LO

LHC


bb → H in SUSY

modified Yukawa couplings in SUSY:λb

λt

=mb

mt

·vu

vd

=mb

mt

· tan β

t

_t

H + h

b

_b

collinear logarithms: ∼ αs ln(mb/MH) ∼ αs ln(5/200)

resummation: bottom parton densities

b_

b

H →

_

H

b

b


bb → H in SUSY


λt

=mb

mt

·vu

vd

=mb

mt

· tan β

t

_t

H + h

b

_b



b_

b

H →

_

H

b

b


bb → H in SUSY


λt

=mb

mt

·vu

vd

=mb

mt

· tan β

t

_t

H + h

b

_b



b_

b

H →

_

H

b

b


pp → H + bb

to yield larger cross sections. Note that closed top-quark loops have not been included in the NNLOcalculation of bb → h [10].

To all orders in perturbation theory the four- and five-flavor number schemes are identical, butthe way of ordering the perturbative expansion is different and the results do not match exactly at finiteorder. The quality of the approximations in the two calculational schemes is difficult to quantify, andthe residual uncertainty of the predictions may not be fully reflected by the scale variation displayed inFig. 8.

σ(pp_→ bb

_h + X) [fb]

√s = 1.96 TeV

µ = (2mb + Mh)/4

Mh [GeV]

bb_

→ h (NNLO)

gg → bb_

h (NLO)

1

10

100 110 120 130 140 150 160 170 180 190 200

σ(pp → bb_

h + X) [fb]

√s = 14 TeV

µ = (2mb + Mh)/4

Mh [GeV]

bb_

→ h (NNLO)

gg → bb_

h (NLO)10

10 2

10 3

100 150 200 250 300 350 400

Fig. 8: Total cross sections for pp(pp) → bbh + X at the Tevatron and the LHC as a function of the Higgs mass Mh with

no b jet identified in the final state. The error bands correspond to varying the scale from µR = µF = (2mb + Mh)/8 to

µR = µF = (2mb + Mh)/2. The NNLO curves are from Ref. [10].

6. Conclusions

We investigated bbh production at the Tevatron and the LHC, which is an important discovery channelfor Higgs bosons at large values of tan β in the MSSM, where the bottom Yukawa coupling is stronglyenhanced [13, 14]. Results for the cross sections with two tagged b jets have been presented at NLOincluding transverse-momentum and pseudorapidity cuts on the b jets which are close to the experimen-tal requirements. The NLO corrections modify the predictions by up to 50% and reduce the theoreticaluncertainties significantly. For the cases of one and no tagged b jet in the final state we compared theresults in the four- and five-flavor-number schemes. Due to the smallness of the b quark mass, largelogarithms Lb might arise from phase space integration in the four-flavor-number scheme, which areresummed in the five-flavor-number scheme by the introduction of evolved b parton densities. The five-flavor-number scheme is based on the approximation that the outgoing b quarks are at small transversemomentum. Thus the incoming b partons are given zero transverse momentum at leading order, andacquire transverse momentum at higher order. The two calculational schemes represent different pertur-bative expansions of the same physical process, and therefore should agree at sufficiently high order. Itis satisfying that the NLO (and NNLO) calculations presented here agree within their uncertainties. Thisis a major advance over several years ago, when comparisons of bb → h at NLO and gg → bbh at LOwere hardly encouraging [1, 16].

7. Acknowledgement

We thank the organizers of the 2003 Les Houches workshop for organizing such a productive and inter-esting workshop.

b_

b

H

_

H

b

b

bb → H: [R.H., Kilgore ’03]

gg → bbH: [Dawson et al. ’04], [Dittmaier et al. ’04]


What I could not talk about. . .

backgrounds

differential vs. inclusive cross sections

behavior of QCD corrections?

most recent development: NNLO Monte Carlo for gg → H[Anastasiou, Melnikov, Petriello ’04]

technical developments(!)

charged Higgs bosons

. . .



backgrounds






. . .



backgrounds






. . .



backgrounds






. . .



backgrounds






. . .



backgrounds






. . .


Summary

main Higgs production modes at LHC:

tt

t

H H

q

q

Vq

V

qt

_t

H

q

q H

V_

V

(+ diffractive)


Summary


tt

t

H H

q

q

Vq

V

qt

_t

H

q

q H

V_

V

(+ diffractive)

combination necessary for Higgs studies


Summary


tt

t

H H

q

q

Vq

V

qt

_t

H

q

q H

V_

V

(+ diffractive)


theory predictions under good control→ triggered many important technical developments


Summary


tt

t

H H

q

q

Vq

V

qt

_t

H

q

q H

V_

V

(+ diffractive)


theory predictions under good control→ triggered many important technical developments

supersymmetry: much wider field,but many results remain valid


Documents

Finding the Higgs · Finding the Higgs Robert Harlander Institute for Theoretical Particle Physics University of Karlsruhe YETI’05, January 5–8, 2005 Robert Harlander — Finding