lhc earch at the s iggs h susysusy08.kias.re.kr/slide/pl/muehlleitner.pdf · 2008-06-18 · (susy)...

(SUSY) Higgs Search at the LHC

Milada Margarete Muhlleitner

(LAPTH)

SUSY2008

The 16th International Conference on Supersymmetry and

the Unification of Fundamental Interactions

June 16-21, 2008, COEX, Seoul, Korea

M.M. Muhlleitner, 16 June 2008, SUSY08, Seoul

SM Higgs Sector - Mass Constraints

• Triviality → upper bound

Vacuum stability → lower bound

Cabibbo,...;Sher;Lindner;Hasenfratz,...;Luscher, Weisz;Hambye,...;...

Hambye,Riesselmann

Λ = 1 TeV : 55 GeV <∼ MH <

∼ 700 GeV

ΛGUT = 1016 GeV: 130 GeV <∼ MH <

∼ 190 GeV

• Fits to electroweak precision data LEP Coll.

0

1

2

3

4

5

6

10030 300

mH [GeV]

∆χ2

Excluded Preliminary

∆αhad =∆α(5)

0.02758±0.00035

0.02749±0.00012

incl. low Q2 data

Theory uncertaintyMarch 2008 mLimit = 160 GeV

EWWG

MH = 87+36−27 GeV, MH <

∼ 190 GeV @ 95% CL

• Direct search @ LEP: [MH = 115.3 GeV]

��

��

��

� � � �

� ��

MH > 114.4 GeV @ 95% CL LEP Coll.


Higgs Boson Search at the LHCSpira

σ(pp→H+X) [pb]√s = 14 TeVMt = 174 GeVCTEQ6M

gg→H

qq→Hqqqq_’→HW

qq_→HZ

gg,qq_→Htt

_

MH [GeV]0 200 400 600 800 1000

10-4

10-3

10-2

10-1

1

10

10 2

0 200 400 600 800 1000

• gg fusion dominant, second largest vector boson fusion

• MH <∼ 140 GeV: H → γγ, (bb)

• 140 GeV <∼ MH <

∼ 1 TeV: H → ZZ(∗) → 4l± (gold plated), H →WW, ZZ → l’s, jets

• 120 GeV <∼ MH <

∼ 200 GeV: H →WW (∗) → l+l−νν (ang. corr.) Dittmar,Dreiner


Higgs Boson Search Reach at the LHC

ATLAS CMS

1

10

10 2

102

103

mH (GeV/c2)

Sig

nal s

igni

fica

nce

H → γ γ ttH (H → bb) H → ZZ(*) → 4 l H → WW(*) → lνlν qqH → qq WW(*) → lνlν qqH → qq ττ qqH → qqZZ → llνν qqH → qqWW → lνjj

Total significance

5 σ

∫ L dt = 30 fb-1

(no K-factors)

ATLAS


T he MSSM Higgs Sector

MSSM Higgs sector – supersymmetry & anomaly free theory ⇒ 2 complex Higgs doublets

neutral, CP-even h, H neutral, CP-odd A charged H+, H−EWSB→

Higgs masses

Mh <∼ 140 GeV

MA,H,H± ∼ O(v)...1 TeV

Ellis et al;Okada et al;Haber,Hempfling;Hoang et al;Carena et al;Heinemeyer et al;Zhang et al;Brignole et al;...

Decoupling limit:

MA ∼MH ∼MH± � v

Mh → max. value, tanβ fixed; h becomes SM-like

Modified couplings with respect to the SM: (decoupling limit Gunion,Haber)

Φ gΦuu gφdd gΦV V

h cα/sβ→ 1 −sα/cβ→ 1 sβ−α→ 1

H sα/sβ→ 1/tgβ cα/cβ→ tgβ cβ−α→ 0

A 1/tgβ tgβ 0

tanβ ↑ ⇒ gΦuu ↓

gΦdd ↑

gMSSMΦV V

<∼ gSM

ΦV V


MSSM Higgs Boson Production at the LHC

Spiraσ(pp→h/H+X) [pb]√s = 14 TeVMt = 174 GeVCTEQ6M

Mh/H [GeV]

tgβ = 3gg→H

Hbb_

Htt_

Hqq

HZ HW

gg→h

hbb_

htt_hZ

hWhqq

h H❍ ❍100 200 500 1000

10-4

10-3

10-2

10-1

1

10

10 2

10 3

10 4

90100 200 300 400 500 600 700800900

σ(pp→h/H+X) [pb]√s = 14 TeVMt = 174 GeVCTEQ6M

Mh/H [GeV]

tgβ = 30

gg→H

Hbb_

Htt_HZ

HW

Hqq

gg→h

hbb_

htt_hZ

hWhqq

h H❍ ❍100 200 500 1000

10-4

10-3

10-2

10-1

1

10

10 2

10 3

10 4

90100 200 300 400 500 600 700800900

ATLAS CMS


Higgs Boson Production in gluon gluon fusion

(i) Dominant: Gluon Fusion pp → gg → HSM/ h, H, A (small & moderate tan β)

p

p

g

g

Q,Qh, H

QCD corrections to top & bottom loops

NLO (SM, MSSM): increase σ by ∼ 10...100% Spira,Djouadi,Graudenz,ZerwasDawson;Kauffman,Schaffer

[moderate for large tanβ ← b-loop]

SM; tgβ <∼ 5: limit MΦ � mt - approximation ∼ 20-30% Kramer,Laenen,Spira


gg→ H at NLO

Spira,Djouadi,Graudenz,Zerwas

K(pp→H+X)√s = 14 TeV

µ = M = MHMt = 175 GeVCTEQ4

Ktot

Kgg

KvirtKqq

Kgq

MH [GeV]50 100 200 500 1000

-0.5

0

0.5

1

1.5

2

2.5

3

10 2 10 3

σ(pp→H+X) [pb]√s = 14 TeV

µ = M = ξ MH

Mt = 175 GeVMH = 150 GeVCTEQ4

NLO

LO

ξ

5

7

10

20

30

50

σ(pp→H+X) [pb]√s = 14 TeV

µ = M = ξ MHMt = 175 GeVMH = 500 GeVCTEQ4

NLO

LO

ξ

1

2

3

5

7

10

6789

10

20

30

40

0 0.5 1 1.5 2 2.5 3 3.5 4

1

2

3

4

56789

10

0 0.5 1 1.5 2 2.5 3 3.5 4






NNLO @ MΦ � mt ⇒ further increase by 20-30%Harlander,KilgoreAnastasiou,MelnikovRavindran,Smith,van Neervenscale dependence: ∆ <

∼ 10− 15%

mt effect on high-energy NNLO K-factor Marzani et al.

Estimate of NNNLO effects improved perturbative convergence Moch,VogtRavindran

Soft gluon resummation: + ∼ 10% Catani,de Florian,Grazzini,Nason

EW 2-loop effects ∼ 5− 8% increase Aglietti et al.;Degrassi,Maltoni


gg→ H at NNLO and beyond

Harlander,Kilgore

10-3

10-2

10-1

1

100 120 140 160 180 200 220 240 260 280 300

σ(pp →H+X) [pb]

MH [GeV]

LONLONNLO

√s = 2 TeV

Moch,Vogt

0

0.5

1

1.5

2

100 120 140 160 180 200MH(GeV)

σ(pp → H+X) [pb]

NLO

N2LO

N3LOapprox.

+ N3LL

√s = 2 TeV

LO

MH(GeV)

σ(pp → H+X) [pb]

NLO

N2LO

N3LOapprox.

+ N3LL

√s = 14 TeV

LO

0

20

40

60

80

100 150 200 250 300






NNLO @ MΦ � mt ⇒ further increase by 20-30%Harlander,KilgoreAnastasiou,MelnikovRavindran,Smith,van Neervenscale dependence: ∆ <

∼ 10− 15%

mt effect on high-energy NNLO K-factor Marzani et al.

Estimate of NNNLO effects improved perturbative convergence Moch,VogtRavindran

Soft gluon resummation: + ∼ 10% Catani,de Florian,Grazzini,Nason

EW 2-loop effects ∼ 5− 8% increase Aglietti et al.;Degrassi,Maltoni

NLO corrections: to squark loops in heavy squark limit Dawson,Djouadi,Spira

full SUSY-QCD corrections in heavy mass limit Harlander,Steinhauser;Harlander,Hofmann;Degrassi,Slavich

mQ<∼ 400 GeV: NLO squark mass effects ∼ 15% Anastasiou,Beerli,Bucherer,Daleo,Kunszt;

Aglietti,Bonciani,Degrassi,Vicini; MMM,Spira

full NLO SUSY QCD calculation Anastasiou,Beerli,Daleo;MMM,Rzehak,Spira


σNLO w/ full squark mass dependence / σNLO in the heavy squark limit

MMM,Spira

√s = 14 TeVtgβ = 3

σ(pp → h/H + X) / σ∞

mt = 174.3 GeVCTEQ6

Mh/H [GeV]

h H❍ ❍

80 100 200 300 500 700 10000.92

0.94

0.96

0.98

1

1.02

1.04

80 90100 200 300 400 500 600 7008009001000

√s = 14 TeVtgβ = 30

σ(pp → h/H + X) / σ∞

mt = 174.3 GeVCTEQ6

Mh/H [GeV]

h H❍ ❍80 100 200 300 500 700 1000

0.75

0.8

0.85

0.9

0.95

1

1.05

1.1

1.15

1.2

80 90100 200 300 400 500 600 7008009001000

no g loops, but bulk of expected SUSY QCD corrections

σ(pp→ h/H + X)/σ∞ up to 20%

Kinks, bumps, spikes: t1¯t1, b1

¯b1, b2

¯b2 thresholds in consecutive order with rising Higgs mass.


Higgs Boson Production in W/Z boson fusion

(ii) W/Z boson fusion: pp → qq → qq + WW/ZZ → qq + HSM/ h, H

W, Z H, h

q

qCahn,DawsonHikasaAltarelli,Mele,Pitolli

Contribution to H → γγ discovery contour; MSSM: h, H → τ+τ−Plehn,Rainwater,Zeppenfeld

Important role in Higgs coupling determination at the LHC Duhrssen et al.Hankele,Klamke,Zeppenfeld,Figy

Typical signature: 2 hard jets with large rapidity interval and no hadronic activity between them

NLO QCD corrections to total rate (SM/MSSM) ∼ 5 to 10% Han,Valencia,Willenbrock

distributions (SM/MSSM) ∼ 20 % Figy,Oleari,ZeppenfeldBerger,Campbell

dominant NLO QCD to H+3j Figy,Hankele,Zeppenfeld

Full EW & QCD corrections ∼ 5% Ciccolini,Denner,Dittmaier ∆theor ∼ 5 %

SUSY QCD corrections small Djouadi,Spira

SUSY EW+QCD corrections small Hollik,Plehn,Rauch,Rzehak


Associated production with a bb pair

(iii) Higgs bb production: dominant MSSM Higgs production mechanism for tanβ >∼ 7



• Four-flavour scheme: LO cxn gg → bbΦ0

g

b

b

Φ0

q

q

logQ2

m2

b

g

g

b

b

Φ0

dominant

Q ∼ ( 110 ... 14 )MΦ

NLO with 0,1,2 high-transverse momentum b jets Dittmaier,Kramer,Spira,Walser;Dawson,Jackson,Reina,Wackeroth

large logs from phase space integration absorbed in bottom PDF

• Five-flavour scheme: LO cxn bb → Φ0

Φ0

b

b

NNLO

g

b

b

Φ0

NLO

Dicus,WillenbrockStelzer et al.;Balazs et al.Campbell et al.Harlander,KilgoreKidonakis

• Detailed comparisons: similar results√

Campbell et al.


Comparison 4- and 5-flavor scheme

Campbell et al.;Harlander,Kilgore

σ(pp → bb_

h + X) [fb]

√s = 14 TeVµ = (2mb + Mh)/4

Mh [GeV]

bb_

→ h (NNLO)

gg → bb_

h (NLO)10

10 2

10 3

100 150 200 250 300 350 400

σ(pp → b/b_

+h + X) [fb]√s = 14 TeV

|ηb/b_ | < 2.5

µ = (2mb + Mh)/4pTb/b

_ > 20 GeV

gg → bb_

+hgb/b

_ → b/b

_ +h

Mh [GeV]

1

10

10 2

100 150 200 250 300 350 400 450 500



• Four-flavour scheme: LO cxn gg → bbΦ0

g

b

b

Φ0

q

q

logQ2

m2

b

g

g

b

b

Φ0

dominant

Q ∼ ( 110 ... 14 )MΦ

NLO with 0,1,2 high-transverse momentum b jets Dittmaier,Kramer,Spira,Walser;Dawson,Jackson,Reina,Wackeroth

large logs from phase space integration absorbed in bottom PDF

• Five-flavour scheme: LO cxn bb → Φ0

Φ0

b

b

NNLO

g

b

b

Φ0

NLO

Dicus,WillenbrockStelzer et al.;Balazs et al.Campbell et al.Harlander,KilgoreKidonakis

• Detailed comparisons: similar results√

Campbell et al.

• Further corrections: ◦ EW corrections to bb→ Φ0: few % (∼ ∆b)Dittmaier,Kramer,Muck,Schluter

◦ dominant t contr. to “NNLO” bbh: few % MH <∼ 120 GeV, several 10 % above Boudjema,

Ninh

◦ SUSY QCD to gg → bbh Gao et al.;Hollik,Rauch

◦ SUSY QCD to bb→ Φ0, bg → bΦ0: few % (∼ ∆b)Dawson,Jackson


Associated production with a tt pair

(iv) Higgs tt production: pp → qq/gg → tt + HSM/ h(H, A)

g

t

t

Φ0

q

q g

g

t

t

Φ0

dominant

Kunszt;Gunion;Marciano,Paige

Significant role: MSMH

<∼ 150 GeV; light scalar MSSM Higgs

• ttH → ttγγ important contribution to H → γγ discovery contour

• ttH → ttbb important at LHC top Yukawa coupling Gunion et al.;Drollinger et al.

• NLO bkg ttbb, ttjj needed

• NLO QCD corrections (SM,MSSM): ∼ +20 % ∆theor ∼ 15 % Beenakker et al.;Dawson et al.

(MSSM QCD corrs: modified t, b Yukawa couplings)

• SUSY QCD corrections: 20-30 % Peng et al.Dittmaier et al. (→ talk M.Spira)


Associated production with a W or Z boson

(v) pp → qq → Z∗/W ∗ → Z/W + HSM/ h, H

W, Z

W, Z

h, Hq

q

Glashow et al.Kunszt et al.

Contribution to Φ→ γγ discovery contour

• NLO QCD corrections (SM/MSSM) ∼ +30% (Drell-Yan) Han,Willenbrock

NNLO QCD corrections (SM/MSSM) ∼ +5-10% Hamberg,Van Neerven, MatsuuraBrein,Djouadi,Harlander

∆theor ∼ 5 %

• SUSY QCD corrections small Djouadi,Spira

• Full EW corrections (SM) ∼ −5-10% Ciccolini,Dittmaier,Kramer


Charged Higgs Production

• Dominant: pp → qq, gg → H− + tb + c.c. g

g

t

b

H−

Bawa eal;Borzumati eal;Belyaev ealNLO QCD & SUSY QCD corrs.: 50...100 % Peng et al.

Dittmaier et al. (→ M.Spira)

scale dependence reduced: ∆ <∼ 15 %

LO cxn: gb → H−t + c.c.

NLO SUSY QCD corrs.: significant Zhu; Plehn; Berger eal;Gao et al.

• H± pair production pp → qq → H+H− q

q

H+

H−

γ, ZNLO QCD corrs.: ∼ 30 % (← Drell-Yan)

genuine SUSY QCD corrs.: small Djouadi,Spira

• pp → gg → H+H− (LO)Willenbrock;Krause eal;Jiang eal;Brein,Hollik;Barrientos eal

pp → bb → H+H− Barrientos eal;Hong-Sheng eal

SUSY-QCD significant

pp → gg → H+W − + c.c. (LO) Barrientos et al.;Brein et al.

pp → bb → H+W −+c.c.

Dicus eal;Barrientos eal;Brein eal;Hollik eal;Zhao ealQCD corrs. moderate


Charged Higgs Boson discovery reach

Berger et al.

10-1

1

200 300 400 500

σtot (pp→tH−+X) [pb]

tanβ = 30

mH[GeV]

σincl,NLO

σincl,LO

σoff-shell

σBW

σsum

mt=mH+mb±2Γt

150

CMS


Search Channels & Backgrounds (1)

Higgs Search in gg fusion CMS

• pp → γγ + X: MSM

Φ<∼ 140 GeV

B bkg measurable from sideband interpolation

accurate theor. predictions exp. acc., detector performance

B H → γγ: full 2-loop QCD+EWPassarino eal;Djouadi eal;Degrassi,Maltoni

NNLO QCD mt →∞ Steinhauser

QCD corrs. to Q loops MMM,SpiraAglietti et al.

SUSY QCD corrs. Degrassi,Slavich

(MH � mlooppart)

B Irreducible bkg

γ

γ

NLO+fragmentation Binoth et al.

up to N3LO Bern,Dixon,Schmidt



• H → W +W − → l+l−νν: 140 GeV <∼ MH<∼ 180 GeV early discovery

no bkg from sidebands

B NLO W+W− bkg w/ spin correlations Dixon eal;Campbell,Ellis

CMS

multiple gluon emission up to NLL Grazzini

B W decay spin correlations in MC@NLO Frixione,Nason,Webber

B gg → W+W− → lνl′ν′Binoth et al; Duhrssen et al.

B tt∗, t∗t∗ LO w/ spin corr.,ΓtKauer,Zeppenfeld

B tt NLO bkg w/ spin corr. (in MC@NLO) Bernreuther eal

• H → ZZ → 4l: 140 GeV MH>∼ 180 GeV CMS

B bkg from data, acc. predictions to study nature of Higgs

B ZZ bkg up to NLO w/ spin corr. Dixon et al.;Campbell,Ellis

soft gluon impact on signal & bkg Frederix,Grazzini

gg → Z∗Z∗ → 4l Binoth,Bauer,Mertsch

B full QCD+EW corr. to H → W +W−/ZZ → 4l Bredenstein et al.


Selection Cuts, Distributions

Impact of HO corrs on rate & shape of distributions may be strongly dependent on cuts!

B NLO gg → H + 1jgg → H + 2j

at large pT for mt →∞De Florian,Grazzini,Kunszt

Campbell,Ellis,Zanderighiin parton level MC progs

Parton shower effects on relevant distributions Del Duca et al.

B MSSM: only LO H + 1jBrein,HollikField,Dawson,SmithLangenegger et al.

B NNLO gg fusion taking into account exp. cuts for

h→ γγ

h→W+W− → l+l−νν

h→ ZZ → 4l

Catani,de Florian,Grazzini

Anastasiou,Melnikov,Petriello

Anastasiou,Dissertori,Stockli

Catani,Grazzini

+ implementation in MC programs

B gg → H : pT distribution, for pT � mH large logs Hinchliff,Novaes;Kauffman

resummed Higgs pT distributionBalazs,Yuan;Berger,Qiu;Kulesza,Sterman,VogelsangBozzi,Catani,de Florian,Grazzini

B NLO W+W− + jDittmaier,Kallweit,UwerCampbell,Ellis,ZanderighiBinoth,Guillet,Karg,Kauer,Sanguinetti

bkg to VBF, gluon gluon fusion


Effects of cuts

NLO,NNLO K-factors vs pvetot

Fixed-order calc valid? Resummation needed?

Anastasiou et al. Anastasiou et al.

K-factors depend strongly on cut value

Fixed order Higgs prod cxn (NNLO) &

MC@NLO (rescaled w/ NNLO/NLO

K fac for σtot)Very good agreement!



Higgs Search in Vector Boson Fusion

B gg → H + 2j (bgk to HWW, HZZ coupling isolation), WW + j, see previous slide

• Φ → γγ:

q

g

g

g

g

γ

γ

+ q

g

g

g

g

γ

γ

B bkg pp→ γγjj desirable

• Φ → τ+τ−: important MSSM discovery channel CMS

B QCD Zjj and EW Zjj bkgs at NLO Campbell,EllisOleari,Zeppenfeld

• Φ → W +W − → l+l−νν: most challenging! ATLAS

B WW bkg at NLO Jager,Oleari,Zeppenfeld+Bozzi

parton-level MC w/ full exp. cuts

B NLO to tt+jet Dittmaier,Uwer,Weinzierl

needed: top decay w/ full spin corrs. & finite width effects


Expected Accuracies

Duhrssen et al. ATLAS

[GeV]Hm110 120 130 140 150 160 170 180 190

(H,W

)2

(H,X

) / g

2g

(H,W

)2

(H,X

) / g

2 g

∆

0

0.2

0.4

0.6

0.8

1

(H,W)2(H,Z) / g2g

(H,W)2) / gτ(H,2g

(H,W)2(H,b) / g2g

(H,W)2(H,t) / g2g

without syst. uncertainty

ATLAS + CMS-1

L dt=300 fb∫each

∫Ldt = 300 fb-1

mA = 150 GeV

tanβ

∆tan

β/ta

nβ (%

)

1 10

4

5

6

7

8

910

20

Kinnunen eal

)2

(GeV/cAm0 100 200 300 400 500 600 700 800 900

(%)

β/t

anβ

tan

∆

0

5

10

15

20

25

30

/lj/jjµe→ττ→SUSYH

ll/lj/jj→ττ→SUSYH

-130 fb

Total uncertainty

= 20

βta

n = 30β

tan = 40β

tan CMS

Stat errors

= 20β

tan = 30β

tan = 40

βtan

L/L = 5%∆ = 20%σ/σ∆

BR/BR = 3%∆

2 = 2450 GeV/ctA2 = 300 GeV/cµ

2 = 200 GeV/c2M

2 = 1 TeV/cSUSYm

= 10βtan

= 10βtan

•δMH

MH∼ 10−3

•δ tan βtan β ∼ 10− 15 %


Higgs Search in SUSY Particle Final States

B Decays in gauginos and sfermions (3rd generation) important, if kinematically allowed.HDECAY

BR(Φ→χχ)tgβ = 3M2 = 140 GeVµ = 160 GeV

A

HH±

MΦ [GeV]100 200 500 1000

BR(Φ→squarks)

tgβ = 3

M~ Q = 400 GeV

At = 1.05 TeV

A

H

H±

MΦ [GeV]300 500 700 1000

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

10 3

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

300 400 500 600 7008009001000

B Four-lepton LHC events from MSSM Higgs boson decays into neutralino and chargino pairs

Event-generator level simulations w/ realistic detector effects and analyses of all significant bkgs

MA (GeV)

tan

β

MSSM Point 1*

from Ref. [8]

∫ Ldt = 100 fb-1

∫ Ldt = 300 fb-1

χ χ~~2

0

20

MA (GeV)

tan

β

MSSM Point 1*

from Ref. [8]

∫ Ldt = 100 fb-1

∫ Ldt = 300 fb-1

Bisset,Li,Kersting,Moortgat,Moretti

(µ, M2, M2, mlsoft, mτsoft

) =

(−500, 180, 90, 250, 250) GeV

Φ0 → χ02χ

02 totally dominates

Part of difficult wedge region (only h discovery)

can be covered


Higgs Search in SUSY cascade decays

B Few scenarios considered Datta,Djouadi,Guchait,Moortgat

Sc3 pp → gg, qq, qq∗, qg → χ±

2 , χ03, χ

04 + X

→ χ±

1 , χ02, χ

01 + h, H, A, H± + X


1 , χ02 + X

→ χ01 + H±, h, H, A + X

0

10

20

30

40

50

60

70

80

90

0 50 100 150 200 250 300 350 400

bb invariant mass (GeV)

Eve

nts

/ 5

GeV

0

10

20

30

40

50

60

70

80

90

0 50 100 150 200 250 300 350 400

bb invariant mass (GeV)

Eve

nts

/ 5

GeV

green - SM tt red - SUSY bkg


Higgs Search in SUSY cascade decays

B Few scenarios considered Datta,Djouadi,Guchait,Moortgat


2 , χ03, χ

04 + X

→ χ±

1 , χ02, χ

01 + h, H, A, H± + X


1 , χ02 + X

→ χ01 + H±, h, H, A + X

Difficult region of low MA and low tanβ can be explored


Conclusions

• Higgs particle searches at the LHC belong to major endeavours

• LHC will find at least one Higgs boson [light scalar]

• Most (SUSY) QCD corrections know

Large corrections in several cases

remaining theoretical uncertainties: ∼ 100 % → <∼ 15 %

• Signal programs available including many of these corrections

(HIGLU,VV2H,V2HV,FEHIP,HNNLO,...)

• NLO MC’s include NLO corrections to many bkg processes, too

(MCFM,MC@NLO,Sherpa,...)

• Some processes still missing (e.g. NLO ttbb), still work to be done


Backup Slides


Expected relative error on σ determination at the LHC

From: Rainwater,Spira,Zeppenfeld

B Sumarizes results byZeppenfeld,Kinnunen,Nikitenko,Richter-Was (2000);Drollinger,Muller,Denegri (2001)(ttH, H → bb, black dotted)Maltoni,Rainwater,Willenbrock (2002)(ttH, H → W +W−)

B

∫L = 200 fb−1, for ttH :

∫L = 300 fb−1


Access to low tan β

Access to low tan β with A → Zh


Higgs Boson Branching Ratios and T otal W idth

HDECAY

BR(H)

bb_

τ+τ−

cc_

gg

WW

ZZ

tt-

γγ Zγ

MH [GeV]50 100 200 500 1000

10-3

10-2

10-1

1

10 2 10 3

• MH <∼ 140 GeV: H → bb dominant

• MH >∼ 140 GeV: H →WW ∗, ZZ∗

• BR(H → tt) up to 20 % above the tt threshold


MSSM Higgs Boson Branching Ratios

HDECAY

BR(h)tgβ = 3

bb_

τ+τ−

cc_

ggWW

γγ

Mh [GeV]

1

BR(h)tgβ = 30

bb_

τ+τ−

gg

WW→

←ZZ

←gg

←cc_

←γγ

Mh [GeV]

1

10-3

10-2

10-1

80 85 90 95 100 10510

-3

10-2

10-1

80 90 100 110 120

BR(H)

tgβ=3bb_

gg

τ+τ−

cc_

bb (tgβ=30)_

τ+τ−(tgβ=30)

MH [GeV]100 200 300 500 1000

BR(H)

tgβ=3

hh hh

WW

ZZ

tt-

ZA

MH [GeV]100 200 300 500 1000

10-2

10-1

1

10 2 10 3

10-2

10-1

1

10 2 10 3


MSSM Higgs Boson Branching Ratios

HDECAY

BR(A)tgβ = 3

bb_

τ+τ−

gg

Zh

tt_

MA [GeV]100 200 500 1000

1

BR(A)tgβ = 30

bb_

τ+τ−

ggtt_

MA [GeV]100 200 500 1000

1

10-3

10-2

10-1

10 2 10 3

10-3

10-2

10-1

10 2 10 3

BR(H±)tgβ = 3

τν

WAcbcs

µν

Wh

tb

MH± [GeV]

100 200 300 500

1

BR(H±)tgβ = 30

τν

cs

cb

µν

tb

MH± [GeV]

100 200 300 500

1

10-3

10-2

10-1

10 2

10-3

10-2

10-1

10 2


MSSM Higgs Mass Limits

B Direct Search at LEP: e+e− → Z + h/H, A + h/H, νeνe + h/H

� ��

�

� ��

��

�

� ��

��

��

� !�

1

10

0 200 400

1

10

mA (GeV/c2)

tanβ

Excludedby LEP

mh-max(c)

Mh/H >∼ 91 GeV

MA >∼ 91.9 GeV

MH± > 78.6 GeV

0.5 < tanβ < 2.4 excluded

(only in this scenario, mt = 174.3 GeV!,

no significant changes for mt = 172.6 GeV)


MSSM Higgs Boson Production at the LHC

Spiraσ(pp→h/H+X) [pb]√s = 14 TeVMt = 174 GeVCTEQ6M

Mh/H [GeV]

tgβ = 3gg→H

Hbb_

Htt_

Hqq

HZ HW

gg→h

hbb_

htt_hZ

hWhqq

h H❍ ❍100 200 500 1000

10-4

10-3

10-2

10-1

1

10

10 2

10 3

10 4

90100 200 300 400 500 600 700800900

σ(pp→h/H+X) [pb]√s = 14 TeVMt = 174 GeVCTEQ6M

Mh/H [GeV]

tgβ = 30

gg→H

Hbb_

Htt_HZ

HW

Hqq

gg→h

hbb_

htt_hZ

hWhqq

h H❍ ❍100 200 500 1000

10-4

10-3

10-2

10-1

1

10

10 2

10 3

10 4

90100 200 300 400 500 600 700800900

Production plots: MS = 1 TeV

• h→ γγ, bb

• H/A→ τ+τ−, µ+µ−

• H± → τντ

• and V V → h, H → τ+τ−


lhc earch at the s iggs h susysusy08.kias.re.kr/slide/pl/muehlleitner.pdf · 2008-06-18 · (susy)...

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