prediction of supersymmetric spectra in the cmssm and nuhm1 with frequentist analysis

Henning Flaecher

CERN

Prediction of Supersymmetric Spectra in the CMSSM and NUHM1

with Frequentist Analysis

in collaboration with:O. Buchmueller, R. Cavanaugh,A. De Roeck, J. Ellis, S. Heinemeyer, G. Isidori, K. Olive, P. Paradisi,F. Ronga, G. Weiglein

Henning Flächer (CERN) SUSY09, Boston 26th June 2009

Introduction How can we best exploit the available experimental data to constrain

New Physics models? Combine as much experimental information as possible Famous example:

Standard Model fit to electroweak precision data

Extend it to include physics beyond the Standard Model Here: Minimal SuperSymmetic Standard Model (MSSM)

Necessary tools: calculations for experimental observables in that model

and a common framework that interfaces between the different calculations

and combines the obtained information

Objectives/Outcome: Fit model parameters in some MSSM scenarios Explore sensitivity of different observables to parameter space


Constraining MSSM parameter space

What observables can be used to constrain the model? Low energy (precision) data

Flavour physics (many constraints from B physics) Other low energy observables, e.g. g-2

High energy (precision) data Precision electroweak observables, e.g. MW, mtop, asymmetries

Cosmology and Astroparticle data e.g. relic density

How to exploit this information? State of the art theoretical predictions (tools) Development of a framework for combination of these tools

Collaboration between experiment and theory

See O. Buchmüller et al., PLB 657/1-3 pp.87-94 and JHEP 0809:117,2008


Common framework development

General overview:

Consistency Relies on SLHA

interface Modularity

Compare calculations Add/remove predictions

State-of-the-art calculations Direct use of code from

experts


Common framework applications

Use case: Fit today’s data

(2-minimisation) Constrain SUSY

parameter space Will become even

more interesting when combined with discoveries

Various modes: Overall best

minimum (MINUIT) 2 scans Markov-Chain

Monte Carlo for parameter space sampling

Henning Flächer (CERN)

List of implemented observables

6th June 2009 SUSY09, Boston 6

Henning Flächer (CERN)6th June 2009

Example Application Constraining the parameter space of the CMSSM

multi-parameter 2 “fit” See O. Buchmüller et al.PLB 657/1-3 pp.87-94

7SUSY09, Boston

Non Universal Higgs Model1: one extra free parameterscalar contributions to Higgs masses at GUT scale allowed to differ from those to squark and slepton masses


Sampling of parameter space with Markov-Chain Monte Carlo type technique

Full sampling of parameter space (~25M points) only observe 1 minimum at

M0 ~ 70 GeV, M1/2 ~ 320 GeV No preference for Focus Point region

CMSSM


Best fit point:M0 = 65 GeVM1/2 = 320 GeVA0 = 113 GeVtanβ = 11.2

Δχ2

M0

M1/2

results still preliminary


Prospects for finding CMSSM at LHC

“CMSSM fit clearly favors low-mass SUSY –A signal might show up very early?!”

“LHC Weather Forecast”

Simultaneous fit of CMSSM

parameters m0, m1/2, A0, tan

(>0) to more than 30 collider and cosmology data (e.g. MW, Mtop, g-2, BR(BX), relic density)

JHEP 0809:117,2008O.Buchmueller, R.Cavanaugh,

A.De Roeck,J.R.Ellis, H.F., S.Heinemeyer,G.Isidori, K.A.Olive,

P.Paradisi, F.J.Ronga, G.Weiglein

SU

SY

09,

Bo

sto

n

9


Particle Masses: CMSSM


g-2(disfavourslarge m12)

bsγ

Extensive sampling allows to take a look at particle spectra

LEP Higgs constraint not included

M1/2 controls gluino, chargino, neutralino masses

also for squarks (M0 < M1/2)

Favoured gluino mass around 650 GeV

Lightest squark around 500 GeV

χ10 χ1

+

g~ t1~

Δχ2

Δχ2

preliminary


Particle Masses: CMSSM


with LEPHiggs constraint

Extensive sampling allows to take a look at particle spectra

LEP Higgs constraint not included

M1/2 controls gluino, chargino, neutralino masses

also for squarks (M0 < M12)

Favoured gluino mass around 650 GeV

Lightest squark around 500 GeV

χ10 χ1

+

g~ t1~

Δχ2

Δχ2

preliminary


NUHM1


Work in progress preliminary sampling of

parameter space 25M points up to tanβ ≤ 45

Observe clear minimum structure again, only one minimum

Best fit point:M0 = 170 GeVM1/2 = 260 GeVA0 = -1330 GeVtanβ = 12.2mH

2 = -1313044 GeV2

results still preliminary

M0

M1/2


What about beyond CMSSM? – NUHM1

NUHM1 fit also favours low-mass SUSY

“LHC Weather Forecast”

SU

SY

09,

Bo

sto

n

Simultaneous fit of NUHM1 parameters m0, m1/2, A0, tan,

mH2

and to more than 30 colliderand cosmology data (e.g. MW,

Mtop, g-2, BR(BX), relic density)

NUHM1

JHEP 0809:117,2008O.Buchmueller, R.Cavanaugh,

A.De Roeck,J.R.Ellis, H.F., S.Heinemeyer,G.Isidori, K.A.Olive,

P.Paradisi, F.J.Ronga, G.Weiglein

Non Universal Higgs Model1:- one extra free parameterscalar contributions to Higgs masses at GUT scale allowedto differ from those to squark and slepton masses

13


g~

Δχ2

χ10

Δχ2

Particle Masses: NUHM1


Non Universal Higgs Model1:

Minima at similar masses as in CMSSM well within LHC

reach not as tightly

constrained towards higher masses

χ1+

t1~

χ10

~gpreliminary


Lightest Higgs Constraint Likelihood profile

for lightest Higgs mass CMSSM: Lightest Higgs just

below LEP bound but

much tighter constrained

than SM Higgs NUHM1:preferred Higgs mass

at ~120 GeV

naturally above LEP limit

but less constrained towards

lower masses


CMSSM

NUHM1


Dark Matter Constraints: CMSSM

Comparison of direct searches with collider searches


withwithoutHiggs constraint

pSI: spin-independent dark matter -

WIMP elastic scattering cross section on a free proton.

Example how combination of direct and indirect measurements can provide information about validityof specific new physics models

preliminary


Cross-section and mass not quite as well constrained

Dark Matter constraint: NUHM1


pSI: spin-independent dark matter -

WIMP elastic scattering cross section on a free proton.

χ10

σpSI

preliminary


Limits on neutralino mass once real data is available exploit correlation between neutralino mass and M1/2

Discovery/Exclusion in M1/2 can be translated into neutralino mass reach

CMSSM vs NUHM1


NUHM1

NUHM1

CMSSM


Conclusions For comprehensive interpretation of LHC data it is necessary to

check for consistency with all available experimental data

Efforts to combine… various sets of experimental constraints in different models and in different ways

…are ongoing

Investigate simple models: CMSSM: provides Higgs mass compatible with LEP limit

but much better constraint would be discoverable at the early stages of the LHC (1fb-1) NUHM1: preferred Higgs value above LEP limit but less

constrained towards lower value Early LHC data will probe these models!

Henning Flächer (CERN)6th June 2009 SUSY09, Boston 20

BACKUP


Omega


CMSSM:Prediction for Omega h2 from all other constraints

prediction of supersymmetric spectra in the cmssm and nuhm1 with frequentist analysis

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