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Search for Superpartners @ Colliders. The Mass Spectrum. Model Dependent. LHC. ILC. Creation and Decay of Superpartners in Cascade Processes @ LHC. weak int's. Strong int's. l,2j,E T. 2l,6j,E T. 2l,2j,E T. 8j,E T. Typical SUSY signature: Missing Energy and Transverse Momentum.
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The Mass Spectrum Model Dependent LHC ILC
Creation and Decay of Superpartners in Cascade Processes @ LHC weak int's Strong int's l,2j,ET 2l,6j,ET 2l,2j,ET 8j,ET Typical SUSY signature: Missing Energy and Transverse Momentum
Background Processes of the SM for creation of Superpartners l,2j,ET 2l,6j,ET 2l,2j,ET 4j,4l,ET The x-sections are usually much smaller than for creation of SUSY
Creation of Gluino @ LHC m0 = 1400 GeV m1/2 = 180 GeV A = 0 sign(μ) = +1 tanβ = 50 σ≈13 pb Signature:4 b-jets + 4 muons + Etmiss Large!
SUSY Signal @ ATLAS Sharp cut NeutralinoPt B mesons Missing Momentum Invariant Mass of lepton pair В-meson free path Pythia within ATHENA, B-vertex taging JINR ATLAS Group
Search for Supersymmetry @ LHC Reach limits for various channels at 100 fb 5 σ reach in jets channel -1
Long-Lived Superparticles The reason for long-lived particles – mass degeneracy with the LSP WMAP LSP charged Long-lived Long-lived Higgs Long-lived EWSB Time of life> 10-10сек, М ~ 100 ГэВ Decay with creation of the secondary vertex or running through the detector The MSSM parameter space Needs the fine-tuning of parameters
The Origin of Dark Matter The Dark Matter is made of: • Macro objects – Not seen • New particles – axion (axino) - neutralino - sneutrino - right neutrino - gravitino - heavy photon - heavy pseudo-goldstone - light sterile higgs mSUGRA Gauge Mediation Not from the SM Little Higgs Models Inert Higgs Model
DM Detection Direct detection Indirect detection • EGRET -> GLAST • Diffuse Gamma Rays • HEAT, AMS01 -> PAMELA • Positrons in Cosmic Rays • BESS -> AMS02 • Antiprotons in Cosmic Rays DAMA, Zeplin, CDMS, Edelweiss No convincing evidence so far Hope for new results soon First Evidence of DM annihilation!
The Lightest Superparticle property signature stable • Gravity mediation jets/leptons • Gauge mediation stable photons/jets lepton stable • Anomaly mediation lepton stable • R-parity violation LSP is unstable SM particles Rare decays Neutrinoless double decay • Modern limit
SUSY DARKMATTER Neutralino = SUSY candidate for the cold Dark Matter Neutralino = the Lightest Superparticle (LSP) = WIMP photino zino higgsino higgsino • Superparticles are created in pairs • The lightest superparticle is stable
DM NEUTRALINO ANNIHILATION FINAL STATES Dominant annihilation x-section: + A bb quark pair B-fragmentation well studied at LEP! Yield and spectra of positrons, gammas and antiprotons well known! -
DM NEUTRALINO ANNIHILATION CROSS-SECTION - Dominant annihilation x-section: + A bb quark pair
GAUGINO CONTENT OF THE LIGHTEST NEUTRALINO The lightest neutralino is almost bino – the superpartner of a photon DM = superpartner of the CMB
Favoured regions of parameter space EGRET region The region is compatible with diffuse gamma ray flux from the DM annihilation It corresponds to the best fit values of parameters tanβ= 51 m0 = 1400 GeV m1/2 = 180 GeV SUSY DM:
Direct Detection of WIMPs WIMPs elastically scatter off nuclei => nuclear recoils Measure recoil energy spectrum in target 0 Spin dependent and indep. Spin independent Number of nuclei2 (coherent scattering on all nuclei!) 0 Spin dependent
DAMA ZEPLIN Edelweiss CDMS Projections DIRECT DM SEARCHES Spin-dependent Spin-independent Predictions from EGRET data assuming Supersymmetry