Prsentation PowerPoint

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Extraction of fundamental parameters
BSM LHC 2009 Boston June 4, 2009 Dirk Zerwas LAL
Orsay

• Introduction
• Vintage Supersymmetry
• Difficult supersymmetry
• Conclusions

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Supersymmetry

• fermion ?boson
• has no problems with radiative corrections
  (quadrat. div.)
• has a light Higgs Boson (lt150GeV)
• interesting pheno at the TeV scale

3 (or more) neutral Higgs bosons h, A, H 1 (or
more) charged Higgs boson(s) H and
supersymmetric particles

• Many different models
• MSSM (low scale many parameters)
• mSUGRA (high scale few parameters)
• DSS (SUSY with heavy scalars)
• GMSB
• AMB
• Additional (s)particles
• NMSSM
• MRSSM/N1/N2 hybrid

• R-parity
• production of SUSY particles in pairs
• (Cascade-) decays to the lightest SUSY particle
• LSP stable, neutral and weakly interacting
  neutralino (?1)
• experimental signature missing ET

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A typical (optimistic) point
Physics Interplay of the LHC and ILC G.
Weiglein et al
gluinos and squarks (not too heavy)
heavy and light gauginos

• t1 lighter than the lightest ?
• ? BR 100 t?
• ?2 BR 90 tt
• cascade
• qL ? ?2 q ? lR l q ? l l q?1

• hard jets with leptons
• invariant mass
• jet-lepton
• lepton-lepton-jet
• lepton-lepton

Higgs boson mass at the LEP limit
light sleptons
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EWPO and inference from current data
Buchmueller et al Phys.Lett.B65787-94,2007 elect
roweak plus dark matter, b?s?, b?µµ CMSSM ?2
slightly better than SM mh1108-103GeV
Buchmueller et al JHEP 0809117,2008 CMSSM best
fit close to SPS1a ?
S. AbdusSalam, B. Allanach, F. Ferhoz, M. Hobson,
F. Quevedo arXiv0904.2548  EWPOdark matter,
superIso Infere on MSSM parameters, difference
log/lin prior should reduce with further data
Log prior
Linear prior
Bayesian analysis shows no preference for sign of
µ
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Understanding SUSYDetermination of
Supersymmetric Parameters
from edges, masses (etc) to fundamental
parameters e.g. mSUGRA m(Smuon) f(m0, m1/2,
tanß) m(Chargino) f(m1/2, tanß,) correlations
exp and theoretical treatment of theory errors! ?
global ansatz necessary
Prospino2 (Plehn)
Eur.Phys.J.C59427-443,2009 Allanach, Hugonie,
Kneur, Djouadi, Mambrini, Muehlleitner,
Heinemeyer, Weiglein, Spira..

• mass spectra and decays SOFTSUSY, SUSPECT,
  FeynHiggs, ISASUSY,SPHENO, SDecay, SUSY-HIT,
  HDECAY, NMSSMtools,
• NLO cross sections from Prospino2.0,
• dark matter micrOMEGAS, DarkSUSY, IsaRED,

Search for parameter point, determine errors
including treatement of error correlations Pionee
rs G. Blair, W. Porod and P.M. Zerwas
(Eur.Phys.J.C27263-281,2003) / Allanach et al.
hep-ph/0403133 FITTINO P. Bechtle, K. Desch, P.
Wienemann with W. Porod (Eur.Phys.J.C46533-544,20
06) SFITTER R. Lafaye, T. Plehn, M. Rauch, D. Z.
(Eur.Phys.J.C54617-644,2008) GFITTER M. Goebel,
J. Haller, A. Hoecker, K. Moenig, J. Stelzer (EW
fit) MasterCode O.Buchmueller et al,
Phys.Lett.B65787-94,2007 Super-Bayes R.R. de
Austri, R. Trotta, (MCMC, collider observables
and dark matter) CMSSM fits and weather
forcasts B. Allanach, K. Cranmer, C. Lester, A.
Weber
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Vintage SUSY Measurements
Experimental studies Talks ATLASCMS Fabienne
Ledroit
LHC lepton energy scale 0.1 LHC jet energy
scale 1 luminosity 100fb-1

• Linear collider
• ee- collisions
• up to 1TeV

Lester, Nojiri, Osland, Polesello and many more
SPS1a

• LHC
• from edges/thresholds to masses toy/fit

for the following continue with vintage
supersymmetry SPS1a as example
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Lagrangian_at_GUT scale mSUGRA

• Sample a multi-dimensional parameter space
• correlated measurements
• find secondary minima

• SFitter
• Markov Chains (efficient sampling in high
  dimensions, linear in number of parameters)
• Full dimensional exclusive likelihood map with
  the possibility of different types of
  projections
• marginalisation (Bayes) introduces a measure
• profile likelihood (Frequentist approach)

• Fittino
• Simulated annealing/Markov chains

Ranked list of minima

• secondary minima exist (LHC)
• discarded by ?2 alone
• interplay with top mass (parameter!)

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Impact of Theory Errors
RFit Scheme Höcker, Lacker, Laplace, Lediberder

• No information within theory errors flat
  distribution

• ILC improves by 3-4x on LHC

• LHCILC better than any machine alone

SFitter
remember the standard model (top quark mass 1GeV
at LHC) 10.

• theory errors impact the expected precision at
  all machines also at LHC

SPA project precision of the theoretical
calculations Eur.Phys.J.C4643-60,2006
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MSSM
19 parameters at the EW scale no unification of
the 1st and 2nd generation

• Sequential use of techniques
• markov flat full Parameter space
• MINUIT in 5 best points
• Markov flat gaugino-higgsino space
• MINUIT on 15 best points
• BW pdf on remaining parameters
• MINUIT on 5 best solutions (all parameters)

• 3 neutralino masses at LHC
• M1, M2, µ
• 8 fold ambiguity in Gaugino-Higgsino subspace at
  the LHC!

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MSSM running up with the LHC
Claire Adam and Jean-Loic Kneur
Extrapolation of gaugino masses of the degenerate
points
True SPS1a
M1 M2 M3
Point 6
M2 M3 M1
Point 6 M1/M2 inversion
M1 M2 M3
M1 M2 M3
Point 3
Point 1
Point 3 Correct hierarchy at EW scale
First order observation gaugino unification in
only 2 of 8 points
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MSSM zooming in on the high scale
Extrapolation of gaugino masses of the true SPS1a
and point 1 (wrong sign(µ))
M1 M2 M3
True SPS1a
M1 M2 M3
Point 1

• Zooming in on the GUT scale
• clear unification for SPS1a (as expected)
• close miss for degenerate point 1 (not
  quantified yet)

exact gaugino unification in only 1 of 8 points
measured at LHC
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MSSM running up with the LHC
Further information from the light generation
sfermions?
Claire Adam and Jean-Loic Kneur
eL eR uR dR q1L
Point 1
True SPS1a
Difference between true SPS1a and point 1
sign(µ), no help from extrapolation of scalar
parameters
BUT stau sector underdetermined (1
measurement) Chose different (also ?2 0)
combination of stau parameters

• robust unification in gaugino sector
• sensitive (coupled RGEs) in scalar sector
• intriguing hints from LHC extrapolation study to
  reduce ambiguities
• BUT have to give up proving unification at the
  LHC at least temporarily (new predictions?)

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MSSM

• LHCILC
• all parameters determined
• several parameters improved

Running up to the GUT scale G. Blair, W. Porod
and P.M. Zerwas (Eur.Phys.J.C27263-281,2003) P.
Bechtle, K. Desch, P. Wienemann with W. Porod
(Eur.Phys.J.C46533-544,2006)
SPS1a (SPA1) dashed bands todays theory errors
included unification measured from low energy
(TeV) data from LHCILC remember all results
valid within a well defined model/hypothesis
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Connection Colliders-Cosmology
E. Baltz,M.Battaglia, M.Peskin, T.Wizansky
Phys.Rev.D74103521,2006 Nojiri et al/Dutta et al

• SUSY breaking parameters (determined)
• spectrum and couplings (deduced)
• darkSUSY, isaRed or micrOMEGAs
• OCDMh2nLSPmLSP (relic density)

NASA/WMAP science team
SPS1a
Temperature range 200µK

• Measurement of the fluctuations of the cosmic
  microwave background
• WMAP
• OCDMh20.1270.01 (astro-ph/0603449)
• Planck (successful launch)
• OCDMh2 2

• MSUGRA SPS1a (central value irrelevant)
• LHC Oh2 0.1906?0.0033
• LHCILC Oh2 0.1910?0.0003
• precision at LHC, permil LHCILC
• theory errors and parameter set dependent!

Comparable precision of CMB and Collider data
possible
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A difficult example SUSY with heavy scalars
Arkani-Hamed Dimopoulos 2004 Giudice, Romanino
2004 W. Kilian, T. Plehn, P. Richardson, E.
Schmidt EPJC 2004
N. Bernal, A. Djouadi, P. Slavich 2007 E. Turlay
(LAL 2009/37)

• Phenomenology
• scalar Mass scale 104 to 16 GeV
• scalars are at MS
• fermions O(TeV)
• SM Higgs h
• effective theory below MS
• at MS matching with complete theory
• and standard RGE

• DSS parameters
• MS decoupling scale, scalar masses
• M1, M2, M3 gaugino mass parameters
• µ Higgs mass parameter
• At trilinear coupling at MS
• tanß mixing angle between Higgs at MS

Parameter determination at LHC possible in this
difficult scenario
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The Higgs sector
Michael Duehrssen arxiv0904.3866
A difficult scenario only the lightest Higgs
boson (120GeV) seen several measurements
possible LHC Gluon fusion and VBF in well
defined final states (many authors and papers)
Duehrssen et al. Phys.Rev.D70113009,2004.
hep-ph/0406323
ttH?bb 50 signal reduction
Hbb J. M. Butterworth, A. R. Davison , M. Rubin,
G. P. Salam Phys.Rev.Lett.100242001,2008.
Theory Errors
Experimental Errors
Correlated measurements and parameters
apply SUSY search techniques for parameter
extraction
Difficulty to be mastered convolution of
GaussianPoissonFlat errors
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The Higgs sector likelihood maps
frequentist
bayesian
Definition ?Hjj deviation of Hjj coupling from
SM value
Loop induced coupling

• general positive correlation among non-Hbb
  couplings due to total width Hbb
• frequentist approach better adapted (no real
  secondary minima)

Measurements at LHC s BR L g2 g2/G
blind to simultaneous coupling/vwidth changes
Add ?Hgg and ?H?? sign preference power of H???
disappears
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The Higgs sector precision
Coupling ratios
Hbb J. M. Butterworth, A. R. Davison , M. Rubin,
G. P. Salam Phys.Rev.Lett.100242001,2008.
Profile likelihood 30fb-1 theory errors

• subjet analysis essential for Hbb!
• 30fb-1 precision 30 to 50 (absolute)
• slightly higher precision for ratios
  (cancelation of errors, but dominated by stat
  errors)

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The Higgs sector new physics
Gluophobic Higgs in SUSY
Gluophobic Higgs A. Djouadi, Phys. Lett. B 435,
101 (1998).

• ggH coupling cancelation of stop and top quark
  contributions?
• loglikelihood as estimator (correlations)
• Higgs mass via VBF
• at 90 CL 46 of the toy-experiments not
  described by SM
• 2 better described by gluophobic scenario

Small enhancement
Reduction to 24 of SM
No deviation from SM
Vintage Supersymmetry Higgs away from decoupling
region
Reduction to 80 of SM
enhancement

• (SPS1a with modified mA, tanß, At to move out of
  decoupling)?
• 90 CL 77 of the toy-experiments not described
  by SM
• 4 better described by SUSY model

• exclusion of the SM possible
• favouring NP wrt SM difficult

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Conclusions

• LHC could provide a wealth of measurements for
  SUSY
• LHC is ready for difficult scenarios DSS,
  Higgs-only
• collider dark matter property predictions
  comparable to WMAP/Planck

• Hope to start testing grand unification soon!

SFitterSuspect
Thank you Tilman Plehn, Peter Zerwas, Laurent
Serin, Claire Adam, Michael Duehrssen, Michael
Rauch
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mSUGRA Errors LHC (and ILC)

• ILC improves by 3-4x on LHC

• LHCILC better than any machine alone

SFitter

• Fittino
• the beginning 1 fb-1
• 1 year low lumi 10 fb-1
• 3 years nominal 300 fb-1
• and then the ILC

• theory errors impact the expected precision at
  all machines also at LHC

SPA project precision of the theoretical
calculations Eur.Phys.J.C4643-60,2006
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MSSM

• LHC
• can assign errors on badly measured parameters
• LHCILC
• all parameters determined
• several parameters improved

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