1. Institute for Anything of the University of Everything Claudia-Elisabeth Wulz SUSY at the LHC Search for Supersymmetry Signals at the LHC C.-E. Wulz (Institute of High Energy Physics) 1 Institute of High Energy Physics of the Austrian Academy of Sciences

2. Motivation 2 n We know that the Standard Model of particle physics must be extended n Supersymmetry is such a possible extension, which can be embedded in higher-ranking theories n Detailed predictions of experimental signatures at the TeV scale exist n Searches can be performed throughout the entire lifetime of the LHC SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics)

3. Experiment 3 SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics) n Data from the CMS experiment will be used. n By now more than 1 fb -1 of integrated luminosity are available. By the end of 2011 3 to 4 fb -1 are expected. The Vienna CMS groups have particular experience in triggering, tracking, recontstruction of tracks and vertices as well as of muons, b’s and  ’s.

4. Research Goals 4 SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics) n Detect deviations from the Standard Model through inclusive analyses n Contribute to determine if a signal can be SUSY or not n Identify SUSY particles and determine their parameters, measure production cross-sections and branching fractions n In parallel: optimize/develop trigger strategies for all analyses Now Beginning of LHC Phase 2 (≈2020)

5. n Use generic signatures to detect deviations from the Standard Model Methodology - generic signatures 5 SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics) Current focus: search in the jets + missing E T + single muon channel DKPI theses: exploit jets + missing E T + single electron channel exploit heavy flavor content of events Leptonic topologies Single lepton Same-sign di-leptons Opposite-sign di-leptons Tri-leptons Di-leptons + photon Hadronic topologies Exclusive n-jet Inclusive ≥3 jet Photon + missing E T

6. Methodology - simplified models 6 SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics) n Use simplified models Example: on-shell effective theories (OSETs) models based on bottom-up approach templates describing particle spectra and decay chains OSETs can be used to tune and interpret searches in a more model- independent way and to serve as interface between theory and experiment

7. Methodology – specific searches 7 SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics) n Use specific event signatures and models Two possible, complementary approaches: perform cut-based analysis use multivariate techniques Example: scalar top production in association with two b-jets in the coannihilation region within the Minimal Supersymmetric Standard Model, with branching fraction close to 100%

8. Synergies within the DK 8 SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics) n Collaboration experiment – theory A. Hoang (University of Vienna) Theory groups (Institute of High Energy Physics) n Development of algorithms (trigger, reconstruction, analysis) R. Frühwirth (Institute of High Energy Physics, TU Vienna) M. Jeitler (Institute of High Energy Physics, TU Vienna) n Experimental techniques, detector issues M.Krammer (Institute of High Energy Physics, TU Vienna)

9. Added value SUSY at the LHC n Students will work in a stimulating environment: investigation of fundamental physics problems world’s most powerful particle accelerator large scientific community but human-sized research groups international, multidisciplinary n Focus on research activities will shift to physics analyses, after long and important development work in triggering and tracking n Reinforcement of collaboration between theorists and experimentalists SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics) 9

10. Thank you for your attention! 10 SUSY at the LHC C.-E. Wulz (Institute of High Energy Physics)