SM@LHC 2017 Amsterdam , May 2-5, 2017 -...

SM@LHC 2017 Amsterdam , May 2-5, 2017

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(Two Higgs Doublet Model) is an extension of Standard Model: second Higgs doublet is added to SM leads to 5 physical states, 3 neutral, 2 charged: CP-even h and H, CP-odd pseudoscalar (A), charged H+ , H- The minimal model has 6 free parameters: Higgs masses mh, mH, mA, mH±

and the ratio of doublet vacuum expectation values tan = v1/v2 and a mixing angle between the CP-even Higgs bosons

(Minimal Supersymmetric Standard Model): extension of SM (each SM particle has a supersymmetric partner). MSSM higgs sector is a particular case of 2HDM type II model

: Higgs singlet is added to MSSM7 physics states, 5 neutral, 2 charged: CP-even H1, H2, H3 , CP-odd A1 A2, charged H+, H –

: (Higgs Triplet Model): simple extension of SM, Higgs triplet is added, lead to 7 physical states: H±±, H±, A, H and h

: (Minimal Left Right Symmetric models ) extension of SM, several variations: e.g. addition of triplet + two doublets (bi-doublet) ….

SM@LHC 2017 Amsterdam May 2 - 5 Yu. Naryshkin, PNPI

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: h/H/A, HWWll,

AZh(Zll,hbb ()), h/H/At𝑡 …

: Hhh → bbττ, hh → bb bb ,

hh → bbγγ, hh → WWγγ, hh → WWbb, hh → WWWW

: H±, H+tb, H+WZ3l+l, H+WZ2l+2j

H+ → μν, H+ → Wh/WA/Wγ, light H+ → cs, cb

: H±± l±l±, H++→ WW


SM@LHC 2017 Yu. Naryshkin, PNPI 4

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ATLAS-CONF-2016-085 SM@LHC 2017 Amsterdam May 2 - 5 Yu. Naryshkin, PNPI

• 2 channels: lep had and hadhad

• Discriminating variable:

Events category: • b-veto : no b-jets in the event • b-tag : at least one b-jet

gg-fusion b-associated production

b-veto b-tag

6 SM@LHC 2017 Amsterdam May 2 - 5 Yu. Naryshkin, PNPI

gg-fusion

b-associated production

MSSM mod

hm

hMSSM

Limits on cross- section BR

Limits on tan

ATLAS-CONF-2016-085

In the context of the MSSM The limits on : <9, m A =200 <50, m A =1200

mod

hm

limits on cross sec. prod from BR = 2.0 pb (ggF) 2.1 pb (b-ass.) (m H/A = 200 GeV ) to BR = 0.013 pb (ggF) 0.014 pb (b-ass.) (mH/A = 1.2 TeV)


• The are two production mechanism: VBF and ggF

• only different-flavor lepton pairs in the final state are considered

• two oppositely-charged leptons and no additional lepton with pT>15 GeV in order to suppress diboson backgrounds

Discriminating variable:

VBF gg-fusion

ATLAS-CONF-2016-074

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ATLAS-CONF-2016-074


Two different hypotheses are tested:

• a narrow width approximation (NWA),

where the width of the heavy Higgs boson is

smaller than the experimental resolution

• large width assumption (LWA), where

widths of 5%, 10%, and 15% of the heavy

Higgs boson mass are considered.

gg-fusion, LWA

gg-fusion, NWA

VBF, NWA

upper exclusion limits (95% CL ): ggF NWA 4.3 pb (mH = 300 GeV) 0.051 pb (mH = 3 TeV) VBF NWA 1.1 pb (mH = 300 GeV ) 0.03 pb (mH = 3 TeV)

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CMS-PAS-HIG-16-023 SM@LHC 2017 Amsterdam May 2 - 5 Yu. Naryshkin, PNPI

Event selection:

• only different-flavour lepton pairs in the final state are considered

• The event is required to have two oppositely-charged isolated leptons

• Events cattegories: 0,1 jets and VBF events

• Discriminating variable:

0 jets events 1 jets events VBF

10

CMS-PAS-HIG-16-023


• limits on the sum of ggH and VBF cross sections times branching fraction were set (ATLAS presented results for two channels separately)

• The limits are interpreted in the electroweak singlet model

• 4 different signal

width have been used,

= 0.09 SM = 0.25 SM

= 0.49 SM = SM Upper limits on cross section BR obtained in the range of: 200 -1000 GeV

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ATLAS-CONF-2016-015


• Search for A CP-odd (pseudoscalar) Higgs boson • Leptonic decay of Z-boson • Analysis was done separately for the events categories:

0 or 2 – leptons and 1 or 2 of b-tagged jets • Resolved or merged jets are considered • The discriminant variable: in the case of “2” reconstructed leptons is invariant mass, in the case of “0” reconstructed leptons is transverse mass:

ggF b-quark associative production

upper limits were set on the production cross sections BR in the range: [4.0 - 0.017] ([6.9 - 0.026] pb) at mA = [220 - 2000] GeV for ggF (b-quark-ass.) production


Results are interpreted in the context of 2HDM (type I and II) as a function of the model parameters tan and cos( -) • The shaded are excluded • A W+ H-, A ZH are

assumed to be forbidden • The width of the A boson

is corrected to the width (A) predicted by the 2HDM.

• Only points in parameter

space where A/mA < 5% are considered.

2HDM Type I 2HDM Type II

ATLAS-CONF-2016-015



• H →hh →bbττ bb2jet(1 b-tag, 2 b-tag) (μτh eτh τhτh) OS final states (τh visible products of a hadronically decaying τ) • discriminant variable – inv mass

CMS PAS HIG-17-002

H,h*

Result interpreted in the context of the hMSSM model, parametrized as a function of the tan and mA

The gray dotted lines plotted for different mH values.


Phys. Rev. D 94 (2016) 052002 Hhhb𝑏 b𝑏

ATLAS-CONF-2016-004 Hhh(b𝑏 )

• Advantages: hb𝒃 decay (BR 58%), clean diphoton signal

• Events are selected if there are at least two isolated photons and exactly two b-jets.

• Discriminating variable: invariant mass • the observed limit is in the range 7.0 - 4.0 pb for

resonances with masses in the range 275–400 GeV.

• “resolved” for low mass and “boosted” for high mass analysis

• Discriminating variable: invariant mass • The cross-section upper limits with ranging from

30 to 300 fb in the mass range between 500 and 3000 GeV.

http://journals.aps.org/prd/abstract/10.1103/PhysRevD.94.052002







17 Yu. Naryshkin, PNPI

• Fully hadronic final state is considered.

• Event selection: (Njets 3), and in the tracker-covered region one b-tagged jet.

• discriminating variable – transverse mass (mT), reconstructed from the hadronic tau decay and MET, and defined as:

• The results are interpreted in the context of the MSSM

benchmark scenario

CMS-PAS-HIG-16-031

bbWHpptbHpp ,

m H± m t – m b m H± > m t – m b

mod

hm


Low mass: m H± m t – m b m H± > m t – m b high mass:

• Exclusion limits in the mH vs tan plane in the context of the MSSM model

• Grey areas are excluded

mod

hm

• Model independent limits on charged Higgs bosons BR and cross section BR

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• The production of a charged Higgs boson in association with a single top quark and its decay via H based on fully hadronic final states

• Event slelction: one and 3 jets with 1 b-tagged jets • discriminating variable is the transverse mass • only high mass case is considered

ATLAS-CONF-2016-088 Yu. Naryshkin, PNPI

interpretation in the hMSSM benchmark scenario. Excluded regions: 42 <tan <60 for m

𝑯+ =200 GeV.

200 <m𝑯+

<540 GeV at tan=60.


• (pp → btH±) × BR(H±tb ) • events must have exactly one lepton (electron or

muon) and 4 jets, 2 b-tagged jets • Discriminating variables: scalar sum pT (HT, had ) of the selected jets in CR Multivariate techniques (BDT) used in SR

ATLAS-CONF-2016-089

The observed (expected) 95% CL upper limits range from BR = 1.09 (1.45) pb at m H+ = 300 GeV to BR = 0.18 (0.17) pb at m H+ = 1000 GeV.

• For mH+ of (300-855 GeV), some values of 0.5<tan <1.7 are excluded • high values of tan are excluded ranging from tan > 44 at 300 GeV to tan > 60 at 366 GeV.


• VBF production mechanism is assumed • Lepontic decay (e,µ) W,Z bosons • Events selection: 3 leptons , 2 jets with large rapidity

separation and high dijet mass, and moderate MET • b-jet veto to suppress top background • Discriminating variable:

CMS PAS HIG-16-027

2015 2016

• Higgs Triplet Model used for interpretation • Limits on the charged Higgs BR are

given for 200 <m H+< 1000 GeV.


23 Yu. Naryshkin, PNPI ATLAS-CONF-2016-051

• Interpretation: LRSM • Decay mode • Events selected: same-charge,

isolated, high-pT electrons inv mass > 300 GeV

eeH

The observed(expected) lower mass limits at 95% C.L.: (100% BR) lower mass limit 420 (460) GeV for: 570 (580) GeV for: (50% BR) lower mass limit 380 (400) GeV for: 530 (530) GeV for:

RH

LH

RH

LH


• Interpretation: LRSM • 100% decay to ee, µµ, eµ, e, µ, and • 3(4) lepton candidates with charge configuration:

(++-),(--+) and (++--) • Discriminating variable is inv mass of SS lepton pairs • m(+ ) = m(++ )

CMS PAS HIG-16-036

kji

lkji

Wqq

Zqq /0

Lower bounds on the ±± mass are set to: 800 - 820 GeV (ee, eµ, and µµ) 714 GeV (e) 643 GeV (µ) 535 GeV () 100% BR is assumed

• The recent results on BSM Higgs searches on LHC with the different final states and in large mass ranges were presented

• No excess of the data over SM prediction were observed and the upper limits on the cross section production and BR were obtained as a function of BSM Higgs boson mass

• The results were interpreted considering different BSM models and the limits on some of the model’s parameters were set: tan , cos (-) and mA

• There are a lot of searches still are in the progress hope to obtain the positive results!




Phys.Lett. B755 (2016) 217-244

• 2HDM used for interpretation

• A →Zh →llττ: ll(μμ or ee) h (μτhad eτhad τhadτhad eμ) • 8 final states were analyzed • Discrimimnant variable – inv

mass (Zh)


• Higgs Triplet Model used for interpretation • VBF production mechanism is assumed • The VBF process reconstructed with two jets, with high

|η| moving in opposite directions. • two OS leptons • reconstructed from two high p T central jets

• Discriminating variable: invariant mass m lljj

PRL 114, 231801 (2015)

/eeZ

qqW


Phys.Lett. B755 (2016) 217-244

The areas highlighted in blue bounded by the black curves mark the observed exclusion

The limit falls off rapidly as mA approaches 350GeV because decays of the A to two top quarks are becoming kinematically allowed.

mH=mA=mH±


Phys. Rev. D 92, 092004

Hhhbb HhhWW Hhhbb Hhhbbbb

Phys. Rev. D 94 (2016) 052002

𝑠 = 8𝑇𝑒𝑉

𝑠 = 13𝑇𝑒𝑉 Hhhb𝑏 b𝑏

𝑠 = 8𝑇𝑒𝑉







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