nmssm higgs search

14-04-201114-04-2011 HEP HEP ConferenceConference 11

NMSSM Higgs SearchNMSSM Higgs Search

0 0 0

1 1 1h 4 2 2 jets

Search for neutral NMSSM Higgs

Studies at 10 TeV, and with the 2010 data @ 7 TeV

Jehad MousaUniversity of Cyprus

ANNUAL MEETING OF THE HELLENIC SOCIETY FOR THE STUDY OF HIGH ENERGY PHYSICS

April 14-16, 2011, University of Patras, Greece


NNMSSMMSSM

The Next-to-Minimal Supersymmetric Standard Model (NMSSM) extends the MSSM by the introduction of a singlet superfield ( )

The NMSSM naturally solves the μ-problem of the MSSM.

The Higgs sector of the NMSSM contains (three CP-even bosons h1, h2, h3 and two CP-odd higgs bosons α1, α2) and two charged higgs bosons (h ).

S


The benchmark pointsThe benchmark points

• The lightest pseudoscalar higgs boson is rather light,

and the lightest CP-even higgs has enough phase space for the decay into two pseudoscalar higgs boson , to be kinematically accessible.

• The BR for the decay is very large and this new channel is the dominant one.

• Concerning the further decay of the lightest pseudoscalars, there are two possibilities: – Either and the boson decays into a pair of b quarks

or a pair of tau leptons, leading to and final states, – or and the dominant decay mode of the boson is

into a pair of tau leptons, leading to final state.

01

40 50M GeV

01a

M

0 0 01 1 1h

0 0 01 1 1h

01

10M GeV

01

0 0 01 1 1 4 ,4h b 2 2b

01

10M GeV

01

0 0 01 1 1 4h


Channels investigated and Channels investigated and associated backgroundassociated background

The signal process:

A Vector Boson Fusion: Two different types of scenarios are

considered, depending on

Scenarios with are disfavored when LEP data for Z2b

and Z4b final states are taken into account.

On the contrary, scenarios with are favored by the

same data and can even account for 2σ excess observed in the

Z2b final state in the vicinity.

0 01 1

2 ( 4.2 ) 2 .b b ba am m m GeV orm m

01

2 bam m

01

2 bam m

01

2 bam m

01

100h

M GeV0 0 01 1 1h a a 4 2 2 jets



higgs-strahlung: 0 0 01 1 1

ll

l

l ,bb,bbWh l a a

l ,bb,

0 0 01 1 1

l l ,bb,bbZh l l a a

l l ,bb,

0 0 01 1 1h a a 0

1h The decay, with produced in higgs-strahlung

with leptonic decays of the W or Z boson, which can give a very

clean and almost background free signal, is one of the most

promising higgs decay channels according to the last

investigation of phenomenological scenarios



* *Z / and W

Background processes:

ZZjj and WZjj production:

TTbar production: t Wb

Zbbbar and Wbbbar

production:

* *Z / and W


Cross Section @ 10 TeVCross Section @ 10 TeV

• Vector Boson Fusion

Mh (GeV) Typical cross –section for VBF (fb)

LO NLO

105 32.68 31.69

115 29.81 28.93

125 27.16 26.39

135 24.95 24.29

145 23.19 22.52

0 0 01 1 1h a a 4 2 2hadronic 6

For L = 200 pb-1, NLO = 6.5 and NNLO = 6.3

2 2 2( ) ( )* ( )* ( ) * ( ) * ( )qqh BR h aa BR a BR BR had

M. Spirq, Fortsch Phys. 46 (1998) 203, http://people.web.psi.ch/spira/proglist.html

92.6% 17.8% 65.4%93.8%


Cross SectionCross Section


μ-τ μ-τ SkimSkim

Muon• Global Muons, Pt > 6 GeV, abs(η) <2.5

Tau• caloRecoTauDiscrimainationByLeadingTrackPtCut: 0.5

• Calo Tau: Leading Track Pt > 5GeV within ΔRmatching = 0.1

Muon-Tau• DiTauAntiOverlapSelector ΔR = 0.01

Sample Gen Events

σ (fb) MC Filter Efficiency

Skim Efficiency

884000 32.68 1 0.87740

ZZ 4l 902140 189.86 0.3165 0.74316

Zbb 4l 1063204 56200 0.007 0.74925

1011062 290900 0.00317 0.86100

0 01 1

0 0 01 1 1 4

5.3 , 105a h

h a a

M GeV and M GeV

tt


Event SelectionEvent Selection

Vertex Selection

p(chi2Vertex) > 0.01

-25 < zVertex < +25 cm

Muon Selection global Muon -2.1 < eta(Muon) < +2.1 Pt(Muon) > 8 GeV Muon Track iso. Muon ECAL iso. Muon pi-Veto Muon Track IP

Tau Selection

Tau not overlapping w. Muon

-2.1 < eta(Tau) < +2.1 Pt(Tau) > 10 GeV Tau lead. Track find. Tau lead. Track Pt Tau 1||3-Prong Charge(Tau) = +/-1 Tau mu-Veto Tau Electron-Veto


Event Selection Event Selection

Muon-Tau Selection

Charge(Muon+Tau) = 0

Acoplanarity(Muon+Tau)

MT (Muon-MET) < 50 GeV

dR(Muon-Tau) < 0.5

a-a Selection

dR(a-a) > 0.3

Acoplanarity (a+a)

MT (a-MET) < 50 GeV

MC

processed

Lw

N

Normalized


CutsCuts

5.031

5.031

5.029

5.029

4.737

4.444

3.815

3.815

3.813

3.712

3.333

3.260

3.194

3.191

131.997

131.997

131.989

131.989

130.895

128.882

126.768

126.768

126.766

126.483

110.132

106.785

104.809

102.897

6.637

6.637

6.633

6.633

6.617

6.503

6.454

6.446

6.420

5.212

5.192

5.188

5.164

5.164

Cut

Htoaa

TTbarFourl

ZZFourl

llbb

gen. Phase-Space

Vertex

p(chi2Vertex) > 0.01

-25 < zVertex < +25 cm

global Muon

-2.1 < eta(Muon) < +2.1

Pt(Muon) > 8 GeV

Tau not overlapping w. Muon

-2.1 < eta(Tau) < +2.1

Pt(Tau) > 10 GeV

Muon Track iso.

Muon ECAL iso.

Muon pi-Veto

Muon Track IP

44.129

44.129

44.118

44.118

43.862

42.785

42.125

42.124

42.091

38.381

35.580

34.986

34.561

34.026


. * visp p 1 5 20

Tau lead. Track find.

Tau lead. Track Pt

Tau 1||3-Prong

Charge(Tau) = +/-1

Tau mu-Veto

Tau Electron-Veto

dR(Muon-Tau) < 0.5

Charge(Muon+Tau) = 0

Acoplanarity(Muon+Tau)

M_{T}(Muon-MET) < 50 GeV

dR(a-a) > 0.3

Acoplanarity(a+a)

M_{T}(Muon-MET) < 50 GeV

3.061

2.975

1.726

1.704

1.484

1.403

0.244

0.224

0.224

0.216

0.145

0.002

0.002

0.002

101.655

100.234

78.144

76.607

71.210

47.493

5.572

3.270

3.270

2.062

1.174

0.002

0.002

0.002

Cuts

4.238

4.123

3.737

3.725

3.503

0.723

0.013

0.007

0.007

0.006

0.003

0.000

0.000

0.000

27.845

25.810

17.517

17.122

14.532

6.261

1.014

0.613

0.613

0.582

0.410

0.000

0.000

0.000


Muon Identification Muon Identification

Muon Reconstruction

( ) ( )

( )T T

T

p RECO p MC

p MC

Muons: “global muons”

PT Resolution

/


Tau Identification Tau Identification

Tau Reconstruction

( ) ( )

( )T T

T

p RECO p MC

p MC

Taus: particle-flow techniques “PFTau”

PT Resolution

/


Missing Transverse Energy (MET)Missing Transverse Energy (MET)

The pfMET algorithm

PMET Resolution MET Resolution


Total number of Taus and muonsTotal number of Taus and muons


Mass ReconstructionMass Reconstruction

PTmiss

vμ

μ

a1τ vτ

μ

had

vμ

a1

h1

τ

vτ

had The mass and PT of the h are

sufficiently large to give a considerable

boost to its decay products. The

direction

of the a1, of the two τ, of the two μ, of

the two hadron and of the three

neutrinos are then nearly parallel.

The missing transverse momentum

originates exclusively from the

neutrinos from the decay chain of the

h.

The masses of the final state leptons

and the a1 are neglected compared to

the typical mass of h1.


Collinear ApproximationCollinear Approximation

1 2 1 2, , , ,

2 1 2 1 2, , , , , ,( ) ( )

x h y h y h x h

miss missx h y h y h y h x h x h

p p p px

p p E p p E

1 2 1 2, , , ,

1 2 1 2 1, , , , , ,( ) ( )

x h y h y h x h

miss missy h x h x h x h y h y h

p p p px

p p E p p E

1 2

1 21 2

h h

a a

E Ex , x

E E

1 2, ,1 2 1 2

, , , , ,1 2

T h T hT a T a T h T h T miss

p pp p p p E

x x

2 21 2 1 2

2 2 21 2 2

1 2

( )

2

a a a a

h h h ha

m p p

m m mm

x x


xx1 1 andand xx2 2 before before Muon-Tau SelectionMuon-Tau Selection


ΔΔR and mass distributions between R and mass distributions between muon-muon-jetjet


ΔΔR and mass distributions between a-aR and mass distributions between a-a


Invariant mass of a and h using Invariant mass of a and h using Collinear Approximation Collinear Approximation


Data and Monte Carlo Samples at 7 Data and Monte Carlo Samples at 7 TeVTeV

Data Run-range

/Mu/Run2010A-Nov4ReReco_v1/RECO 136033-144114

/Mu/Run2010B-Nov4ReReco_v1/RECO 146428-149442

Trigger Path

HLT_Mu9, HLT_IsoMu9, HLT_Mu11, HLT_Mu15, HLT_IsoMu13

HLT_IsoMu9_PFTau15, HLT_IsoMu11_PFTau15

Sample Gen Events

σ (fb)(NLO)

MC Filter Efficiency

Skim Efficiency

693000 14.44 1 0.73440 01 1

0 0 01 1 1 4

9 , 120a h

h a a

M GeV and M GeV

Monte Carlo


Cut Data Htoaagen. Phase-Space 5091469.0000 0.5220Muon Trigger 2274012.0000 0.3556Data quality 2274012.0000 0.3556Vertex 2274012.0000 0.3556Vertex quality 2274012.0000 0.3556-24 < zVertex < +24 cm 2274012.0000 0.3556global Muon 2274012.0000 0.3552-2.1 < eta(Muon) < +2.1 2214682.0000 0.3551Pt(Muon) > 9 GeV 2152200.0000 0.3538Tau not overlapping w. Muon 2150401.0000 0.3537-2.3 < eta(Tau) < +2.3 2148890.0000 0.3537Pt(Tau) > 10 GeV 1839265.0000 0.3439Muon VBTF id. 1627993.0000 0.3391Muon iso. 545575.0000 0.3385Muon Track IP 545575.0000 0.3385Tau lead. Track find. 545575.0000 0.3385Tau lead. Track Pt 538077.0000 0.3314Tau 1||3-Prong 538077.0000 0.3314Charge(Tau) = +/-1 538077.0000 0.3314Tau mu-Veto 198173.0000 0.3176Tau e-Veto 196006.0000 0.3169dR(Muon-Tau) < 0.5 3662.0000 0.0549M_{T}(Muon-MET) < 40 GeV 3473.0000 0.0463P_{#zeta} - 1.5*P_{#zeta}^{vis} > -20 GeV 2724.0000 0.0401not Charge(isoMuon+isoMuon) = 0 2722.0000 0.0383dR(a-a) > 0.3 45.0000 0.0192Acoplanarity(a+a) 43.0000 0.0164M_{T}(aa-MET) < 50 GeV 43.0000 0.0095no E_{T} > 20 GeV central Jet with b-Tag 41.0000 0.0095Charge(Muon+Tau) = 0 27.0000 0.0095charge = 0 16.0000 0.0041


Efficiency SelectionEfficiency Selection

Cut Data_MuTau Htoaa------------------------------------------------------------------------------------------------gen. Phase-Space 1.0000 1.0000Muon Trigger 0.4466 0.6813Data quality 0.4466 0.6813Vertex 0.4466 0.6813Vertex quality 0.4466 0.6813-24 < zVertex < +24 cm 0.4466 0.6813global Muon 0.4466 0.6804-2.1 < eta(Muon) < +2.1 0.4350 0.6803Pt(Muon) > 9 GeV 0.4227 0.6777Tau not overlapping w. Muon 0.4224 0.6776-2.3 < eta(Tau) < +2.3 0.4221 0.6775Pt(Tau) > 10 GeV 0.3612 0.6588Muon VBTF id. 0.3197 0.6496Muon iso. 0.1072 0.6484Muon Track IP 0.1072 0.6484Tau lead. Track find. 0.1072 0.6484Tau lead. Track Pt 0.1057 0.6349Tau 1||3-Prong 0.1057 0.6349Charge(Tau) = +/-1 0.1057 0.6349Tau mu-Veto 0.0389 0.6084Tau e-Veto 0.0385 0.6070dR(Muon-Tau) < 0.5 0.0007 0.1051M_{T}(Muon-MET) < 40 GeV 0.0007 0.0886P_{#zeta} - 1.5*P_{#zeta}^{vis} > -20 GeV 0.0005 0.0768not Charge(isoMuon+isoMuon) = 0 0.0005 0.0734dR(a-a) > 0.3 0.0000 0.0368Acoplanarity(a+a) 0.0000 0.0314M_{T}(aa-MET) < 50 GeV 0.0000 0.0183no E_{T} > 20 GeV central Jet with b-Tag 0.0000 0.0182Charge(Muon+Tau) = 0 0.0000 0.0182charge = 0 0.0000 0.0079


mass distributions mass distributions


ΔΔR and mass distributions between R and mass distributions between muon-muon-jetjet


ΔΔR and mass distributions between a-aR and mass distributions between a-a


ConclusionConclusion

Results of a search for NMSSM neutral Higgs to four taus productions in the channel 2mu + 2tau have been presented.

No evidence fo a NMSSM neutral Higgs signal in the proton-proton collision data collected by the CMS experiment in 2010 is found.

7s TeV


ThanksThanks

We acknowledge support from Research Promotion Foundation (IPE) cyprus

nmssm higgs search

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