Status of SUSY Higgs Physics
Monoranjan Guchait
TIFR, Mumbai
EWSB & Flavors in the light of LHC
February 20-22, 2014
IIT Guwahati
My sincere apology
If I miss your work and references
Outline
Higgs discovery.
Higgs in Supersymmetry and related
Phenomenology.
Higgs in non-minimal model
Discovery of Higgs
Signal observed
above the
background
about 4.7σ
level
Talk by Manas
Higgs Properties
i 
[ j h  Br(h  i)]observed
[ j h  Br(h  i)]
μ=0.80 ±0.14
̴ 20% uncertainty.
With updgraded LHC,
this can come down
to 8-10%
Spin 0+ is favored
What it is?
Couplings to WW, ZZ and γγ are as expected
in SM.
 Couplings are proportional to Masses as predicted
by Higgs mechanism.
Hence, it is a
“125 GeV Boson/new state”….
But it is a Higgs Boson
Is it “the SM Higgs Boson” or “a Higgs boson” from
some other model..or something else..
Higgs is discovered
But….
No evidence of any New Physics
…..raising many uncomfortable questions
Higgs and New Physics
But a very serious implications are there for BSM
Data is compatible with SM , but sensitivity is 1520% can constrain BSM.
Some models are already “closed”: Higgsless model,
fermiophobic, gauge phobic, fourth generation,
extreme technicolour..
Some models are under tension, many other extension
of Higgs model, private, portal light technicolor
Some models are very much constrained….
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
Stabilization of Higgs mass,
Hierarchy problem, m(Higgs)<<M(planck)
| f | B 
The MSSM: particle content
+ 2 Higgs doublets
Supersymmetry is not an exact symmetry
100+ parameters
Higgs Sector in SUSY
Higgs Masses
Higgs masses are calculable: M A , tan  tan  vu
vd

5 Higgsses: h, H , A, H
At tree level, lightest Higgs mass :
Lightest Higgs mass at 1-loop
Stop masses play an important role, connected with
the Higgs
Stop Sector
Stop mixing matrix in
~
~
the basis :
tL, tR
X t  A t   cot
~ ~
~ ~
tL , tR  t1 , t2
Lightest Higgs masses
M  M cos 2  M
2
h
2
Z
2
2
h
X t  0( 6M S ) No(Maximal) mixing
At 1-loop correction , ̴ 20-25 GeV for stop
masses < 1 TeV and no mixing scenario
Upper bound on lightest Higgs Mass
M  M cos 2  M
2
h
For MSUSY ̴ 1 TeV.
2
Z
2
2
h
M h  135 GeV
An upper bound of 135 GeV of lightest higgs
can be achieved
M
Very strong prediction
Higgs Masses
Implications
A 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 mass
Codes SoftSUSy, Spheno, and SusPect calculates
the Higgs mass full One loop + dominant 2 loop
contributions from top/stop loops
Allanach, et. Al., Porod et. Al, Djouadi et. A
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.
Harlander et. Al.
FeynHiggs version 2.10 full one loop + two loop
leading and subleading contribution + resummation
of leading and next to leading contributions
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 MSSM
In 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:
W  H u H d  ....
If μ is generated dynamically, can be controlled.
NMSSM Model
The superpotential,
1 3
W  SH u H d  S  ....
3
1
2
2
3
Vsoft  ms | S | A SH u .H d  A S  ....
3
 ,  : dimensionless
Four new parameters :
A , A
: dimension full ̴ MSUSY
Some additional terms are not considered in general MSSM,
like tadpole terms etc.
NMSSM: Higgs Potential
Tree level Higgs potantial:
With:
Higgs spectrum
Mass terms :
7 Higgsses
H

CP even: H1 , H 2 , H 3
CP odd: A , A
1
2
Singlet like
,  , A , A , eff , M A , tan
NMSSM: μ problem
A vev <S> of S, of the order of the weak or SUSY breaking
scale generates μ-term with
eff    S 
It solves mu problem.
Phenomenological constrained , lighter chargino > 100 GeV,
 eff  100GeV
 S  100GeV / 
Lightest Higgs Mass
The lightest Higgs mass:, the SM like , largest coupling with
the gauge boson,
M  M cos 2   v sin 2
2
h
2
Z
2
2 2
2
Contribution due to the singlet int
For 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
M  M cos 2   v sin 2   corr
2
h
2
Z
2
2 2
2
Loop level contribution make Higgs mass
favorable value
Lightest Higgs Mass
Mt=178 GeV
MSSM
Mt=178 GeV
Mt=171.4 GeV
MSSM
Mt=171 GeV
Ellwanger and Hugonie, ‘06
All Higgs Masses
Lightest Higgs Mass SM like
Tree level mass
L. Hall et. al. ‘11
Higgs Mixings
Mixing of CP odd Higgs
 A2  cos A Sin A   P1 
 A    sin  cos   P 
A
A  2 
 1 
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,
H i  Oij S j
Oij is a diagnolizing matrices and also determine
couplings., it controls Couplings.
SUM RULES
g ZZH i  OH
i
S2
g ZAH  OHi S1 Sin A
g ZA 2 H i  OHi S1 Cos A
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 couplings
with fermions and gauge bosons, then it is difficult to
search those higgs masses at the the collider.
ZZH reduced couplings
Non observation of Higgs in LEP


e e  Z  ZH i
g ZZH i   i

2
i
1
Light CP scalars are not ruled
out by LEP, because of reduced
couplings.
For ξ ̴ 0, the H1 is difficult to produce, H2 is sensitive to Higgs
searches, possibility of another lighter Higgs to exist.
NMSSM Higgs in in B-Factory
Prasad, Bipul, Poulose, 12
A1  2
NMSSM Higgs at the LHC
h  a1a1  4
Higgs production at the LHC
Signal depend on the standard higgs discovery modes
NMSSM Higgs at the LHC
Higgs 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
Outlook
Discovery 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 discoverin
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