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Status of SUSY Higgs Physics Monoranjan Guchait TIFR, Mumbai EWSB & Flavors in the light of LHC...

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Status of SUSY Higgs Physics Monoranjan Guchait TIFR, Mumbai EWSB & Flavors in the light of LHC February 20-22, 2014 IIT Guwahati
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Status of SUSY Higgs Physics

Monoranjan Guchait TIFR, Mumbai

EWSB & Flavors in the light of LHC February 20-22, 2014 IIT Guwahati

My sincere apologyIf I miss your work and references

Outline

Higgs discovery.

Higgs in Supersymmetry and relatedPhenomenology.

Higgs in non-minimal model

Discovery of Higgs

Signal observed above the backgroundabout 4.7σ level

Talk by Manas

Higgs Properties

)]([

)]([

ihBr

ihBr

hj

observedhji

μ=0.80 ±0.14

� 20% uncertainty.With updgraded LHC, this can come down to 8-10%

Spin 0+ is favored

What it is?

Hence, it is a “125 GeV Boson/new state”….

But it is a Higgs BosonIs it “the SM Higgs Boson” or “a Higgs boson” from some other model..or something else..

Couplings to WW, ZZ and γγ are as expected in SM. Couplings are proportional to Masses as predicted by Higgs mechanism.

No evidence of any New Physics

…..raising many uncomfortable questions

But….

Higgs is discovered

Higgs and New PhysicsBut a very serious implications are there for BSMData is compatible with SM , but sensitivity is 15-20% can constrain BSM.Some models are already “closed”: Higgsless model, fermiophobic, gauge phobic, fourth generation, extreme technicolour..

Some models are very much constrained….

Some models are under tension, many other extension of Higgs model, private, portal light technicolor

Is SM can be regarded as Theory of everything?Is the SM a complete theory? Most probably answer is NO.

Many issues(Th+Exp) need to understand, Hierarchy problem.. Neutrino mass, Origin of DM ………………

Beyond SM

Supersymmetry and many of its variations

Extra dimension,

Kaluza Klein,

Composite Higgs

Little Higgs,

Littlest Higgs ………………….

Higgs and Supersymmetry

Implication in SUSY

The MSSM: particle content

+ 2 Higgs doublets

100+ parameters

Stabilization of Higgs mass, Hierarchy problem, m(Higgs)<<M(planck)

Bf ||

Supersymmetry is not an exact symmetry

Higgs Sector in SUSY

Higgs Masses

At tree level, lightest Higgs mass :

Higgs masses are calculable:d

u

v

vtantan,AM

HAHh ,,,5 Higgsses:

Lightest Higgs mass at 1-loop

Stop masses play an important role, connected with the Higgs

Stop Sector

Stop mixing matrix in the basis : RL tt

~~,

cot AX tt

21RL t~,t~t~,t~

Lightest Higgs masses2222 2cos hZh MMM

)6(0 St MX No(Maximal) mixing

At 1-loop correction , 20-25 GeV for stop ��masses < 1 TeV and no mixing scenario

Upper bound on lightest Higgs Mass2222 2cos hZh MMM

Very strong prediction

M

For MSUSY 1 TeV. �

An upper bound of 135 GeV of lightest higgs can be achieved

135hM GeV

Higgs Masses

ImplicationsA Higgs of mass 125 ±2 GeV is observed.

•What are the implications In SUSY models?

•What happens to the Higgs sector?

What are the implications of Higgs discovery in other particle searches, in particular stop searches?

Lightest Higgs mass and stop sector

Maximal mixing is favored, otherwise, requires heavy stop

Hall et. al ,12

Lightest Higgs mass and stop sector

In pMSSM Large MS values with moderate mixings and high tanβ are preferred

Djouadi et. al ‘12

Prediction for stops

• For large mixing, stop masses are within the reach of LHC and if it found, then this form of MSSM may be valid.

• If LHC does not find stop, need to think some other form of SUSY models.

Stop searches at the LHC

Stop mass 500-600 GeV excluded depending on LSP mass. �

Improved calculation of Higgs massCodes SoftSUSy, Spheno, and SusPect calculates the Higgs mass full One loop + dominant 2 loop contributions from top/stop loops

Recent calculation taking leading Three loops using DR or a hybrid renormalization scheme for stop sector where is the numerical evaluation Depends on various SUSY hierarchies.

FeynHiggs version 2.10 full one loop + two loop leading and subleading contribution + resummation of leading and next to leading contributions

Allanach, et. Al., Porod et. Al, Djouadi et. Al.

Harlander et. Al.

Heinemeyer et. Al

Improved calculation of Higgs Mass

Heinemeyer et. al. 1312.4937

Impact on Models

O. Buchmuller, et. al 1312.5233

MA-tanβ exclusion

MH-mod scenario•mh-max scenario was designed to get large Higgs mass , with sparticle masses set to > 1 TeV.•Now, with the present Higgs mass, relaxing mh-max scenario, possible to obtain desired Higgs mass

Mh-mod scenario:MA-tanβ exclusion

MSSM: Charged Higgs

Beyond MSSMIn MSSM, getting the correct Higgs mass is not so trivial. Need higher SUSY scales, fine tuning which is not very interesting from phenomenological point of view.

May be LHC data give hints to go beyond MSSM, (M+1) SSM= NMSSM

μ-problem

In MSSM:.... duHHW

If μ is generated dynamically, can be controlled.

NMSSM Model

The superpotential,....

3

1 3 SHSHW du

....3

1.|| 322 SAHSHASmV dussoft

Four new parameters : ,

AA ,: dimensionless

: dimension full M � SUSY

Some additional terms are not considered in general MSSM, like tadpole terms etc.

NMSSM: Higgs Potential

With:

Tree level Higgs potantial:

Higgs spectrum

Mass terms :

7 Higgsses

Singlet like CP even: 321 ,, HHH

21 , AACP odd:

H

tan,,,,,, Aeff MAA

NMSSM: μ problem

Seff

A vev <S> of S, of the order of the weak or SUSY breaking scale generates μ-term with

It solves mu problem.

Phenomenological constrained , lighter chargino > 100 GeV,

GeVeff 100/100GeVS

Lightest Higgs MassThe lightest Higgs mass:, the SM like , largest coupling with the gauge boson,

2sin2cos 222222 vMM Zh

Contribution due to the singlet intFor large values of λ, and for small tanβ, the second term grows, possible to achieve larger Higgs mass at tree level.

For λ 0.7 – 0.8, Higgs mass cannot be raised above �125 GeV at tree level.

To recover 125 GeV Higgs mass, we need, another � 25 GeV contribution to the tree level mass.

Higgs Mass at one loop

corrZh vMM 2sin2cos 222222

Loop level contribution make Higgs mass favorable value

Lightest Higgs Mass

Ellwanger and Hugonie, ‘06

Mt=178 GeV

Mt=171.4 GeVMSSMMt=178 GeV

MSSMMt=171 GeV

All Higgs Masses

Lightest Higgs Mass SM like

Tree level mass

L. Hall et. al. ‘11

Higgs MixingsMixing of CP odd Higgs

2

1

1

2

cossin

cos

P

PSin

A

A

AA

AA

P2 is singlet like , If MA is large, mixing is small, A1 is completely singlet like A2 has finite singlet component.

And for CP even Higgs, jiji SOH

Oij is a diagnolizing matrices and also determine couplings., it controls Couplings.

SUM RULES

2SHZZHii

Og

ASHZAH SinOgi

1

ASHHZA CosOgii

12

Higgs couplings•The treel level couplings between charged Higgs and fermions/gauge bosons sams as MSSM

•Couplings A1,2 to SM particles are same as MSSM, but multiplied by a dilution factors, related with mixings

•Coulings for h1 and SM particle can be read off by replacing Cosα and sinβ by the i-th eigen vector of diagonalizing matrices.

•A pure singlet SU(2) components has valising couplingswith fermions and gauge bosons, then it is difficult to search those higgs masses at the the collider.

ZZH reduced couplings

iZZH ig

iZHZee Non observation of Higgs in LEP

12 iLight CP scalars are not ruled out by LEP, because of reduced couplings.For ξ 0, the H � 1 is difficult to produce, H2 is sensitive to Higgs searches, possibility of another lighter Higgs to exist.

NMSSM Higgs in in B-Factory

21 A

Prasad, Bipul, Poulose, 12

NMSSM Higgs at the LHC

411 aah

Higgs production at the LHCSignal depend on the standard higgs discovery modes

NMSSM Higgs at the LHCHiggs discovery is same as MSSM channels, but sensitivity depends on the doublet-singlet mixings.Interestingly, higgs to higgs decays, h→AA decays give rich phenomenology. Gunion et. Al., Poulose, Moretti et. al. ,

Dproy, Drees, MG, ….

If lighter state , possibly below LEP limits, is SM like and strongly mixed, less coupling with b-quarks, enhanced decay rates In photonic channel.

G. Belanger et. al ‘12, ….

There are scenario where the SM like state is H2 and the lightest state is H1(70 – 100 GeV), singlet like.Distinguishing feature of NMSSM

OutlookDiscovery of 125 GeV Higgs open up new era in particle physics. Although, it is very much SM-like, possibility of other BSM are not ruled out. May be , this Higgs is the first piece of BSM, which has been discovered.

In minimal Supersymmetry, it can be confirmed by discovering sparticles, mainly lighter Stop, and non-minimal SUSY model, in addition more lighter states of Higgs are required to be discovered.

A rich phenomenology and experimental program is ahead in the next generation of LHC.

Thank you


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