Overview of SUSY phenomenology at the LHC

1. Overview of SUSY phenomenology at the LHC Are R. Raklev CERN / University of Bergen TexPoint fonts used in EMF. Read the TexPoint manual before you delete this box.: AAAAAAAA

2. Content • SUSY models • (mSUGRA?) Signatures • Measuring masses • R-parity conserving vs. R-parity violating • Long lived charged sparticles • Finding that it’s SUSY • Lack of conclusions Overview of SUSY phenomenology

3. Warning Label • Not an experiment talk • No motivation slide • Not complete (not even close) • Also, apologies for any stupid jokes... Overview of SUSY phenomenology

4. SUSY models SUSY MSSM GMSB mSUGRA NMSSM Split SUSY AMSB Will keep to the MSSM subset of all SUSY models Overview of SUSY phenomenology

5. (mSUGRA) Signatures [Drawing by C. Lester] Overview of SUSY phenomenology

6. (mSUGRA) Signatures We expect (or perhaps hope for?): • Missing energy – from ”missing” LSP • Hard jets – from gluino/squark production • Leptons – from gaugino decays Overview of SUSY phenomenology

7. (mSUGRA) Signatures We expect (or perhaps hope for?): • Missing energy – from ”missing” LSP • Hard jets – from gluino/squark production • Leptons – from gaugino decays However: • The LSP might decay (R-parity violation) • We can have a metastable NLSP (GMSB, GDM etc.) • Squarks and sleptons may be too heavy to be produced(Split SUSY) • The whole SUSY spectrum might be quite degenerate(Mixed modular anomaly mediation, MMAM) [Choi et al 2005] Overview of SUSY phenomenology

8. (mSUGRA) Signatures Cross sections for gluino / squark production very probably several orders of magnitude below SM background [CMS collaboration] Overview of SUSY phenomenology

9. with lepton veto • One lepton channel • Two opposite sign (OS) leptons • Two same sign (SS) leptons (mSUGRA) Signatures CMS 5 reach for R-parity conserving mSUGRA in various inclusive channels: [CMS collaboration] Overview of SUSY phenomenology

10. Effective mass Effective mass, an effective discriminant between SUSY and SM background. Open circles are SUSY events, hatched histogram total SM background. [ATLAS TDR, 1999] Overview of SUSY phenomenology

11. Effective mass [ATLAS TDR, 1999] Overview of SUSY phenomenology

12. Effective mass [ATLAS TDR, 1999] [Asai, TeV4LHC workshop, 2005] Overview of SUSY phenomenology

13. Effective mass Progress towards a better understanding of SM multi-jet backgrounds Attempt to use PS and ME matching to estimate multi-jet backgrounds. Results from Tevatron very important! [Asai and Sasaki, hep-ph/0608322] Overview of SUSY phenomenology

14. Measuring masses • With escaping neutalinos we must study the kinematics of the detectable decay products of decay chains to measure masses • Let’s take the following decay chain as an example Overview of SUSY phenomenology

15. Measuring masses • The distribution of the invariant mass of the two leptons can be shown to have a kinematic edge (endpoint) at Overview of SUSY phenomenology

16. Kinematic edges SPS1a [Gjelsten, Miller, Osland, hep-ph/0410303] Overview of SUSY phenomenology

17. Kinematic edges SPS1a SPS1a SPS1a [Gjelsten, Miller, Osland, hep-ph/0410303] Overview of SUSY phenomenology

18. Kinematic edges Drawbacks: • We must manage to identify the correct jets and/or leptons • Fitting endpoints is a tricky buisness: Multiple solutions, feet • Very good at mass differences, very bad at absolute mass SPS1a Overview of SUSY phenomenology

19. Kinematic edges Drawbacks: • We must manage to identify the correct jets and/or leptons • Fitting endpoints is a tricky buisness: Multiple solutions, feet • Very good at mass differences, very bad at absolute mass • What did we measure? Identification of decay chain • Does not use all information Improvements: • Use complete distribution, not only endpoint [Miller, Osland, ARR, hep-ph/0510356] Overview of SUSY phenomenology

20. Other techniques Three unknown momenta components Mass relation method: Only four constraints, but next event has only three more unknowns! Four unknown masses [Kawagoe, Polesello, Nojiri, hep-ph/0402295] Overview of SUSY phenomenology

21. To R-parity or not to R-parity RPC RPV RPV [Drawings by C. Lester] Overview of SUSY phenomenology

22. To R-parity or not to R-parity SM SUSY Overview of SUSY phenomenology

23. RPV • Lepton number violating couplings: • Baryon number violating couplings: • Strong bound on most couplings, • Will imitate RPC if • No missing energy? Not neccessarily true for lepton number violation. Overview of SUSY phenomenology

24. Long live the Sparticles! A number of models exist that can have long lived charged sparticles: In principle no transverse momentum imbalance, but sometimes slow sparticles! Overview of SUSY phenomenology

25. Long live the Sparticles! Many interesting experimental signatures: • Slow, muon-like particles. If we can measure Time-of-Flight: • High ionization • Late decays & trapped particles • Charge flipping (R-hadrons) [Ellis, ARR, Øye, hep-ph/0607261] Overview of SUSY phenomenology

26. Long live the Sparticles! Many interesting experimental signatures: • Slow, muon-like particles • High ionization • Late decays & trapped particles • Charge flipping (R-hadrons) Overview of SUSY phenomenology

27. Finding SUSY vs. finding it’s SUSY Assuming that we find a 5 deviation from the SM in some channel, or even measure the masses of some particles, how do we know if it’s SUSY? For example, can we determine spin in our decay chains? [A. Barr, hep-ph/0405052] Overview of SUSY phenomenology

28. What I haven’t said • NMSSM and other non-minimal models • LFV (through slepton mixing) • Gaugino mixing matrices (estimating DM density) • SUSY higgs sector (see Filip Moortgat’s talk) • Pluss many other things I’ve forgotten about • Including also not saying anything about most of the around 12,000 papers on SPIRES with ”SUSY” or ”supersymmetry” in the title! Overview of SUSY phenomenology

29. [With apologies to D. Kazakov for stealing his joke from ICHEP’06] Overview of SUSY phenomenology

30. Backup slide Green areas in mSUGRA plane shows the existence of the usefull decay chain: Overview of SUSY phenomenology

31. Backup slide Early stage 5 reach contours for missing energy channel. [Tovey, 2002] Overview of SUSY phenomenology

32. Backup slide [Kawagoe, Nojiri, hep-ph/0606104] Overview of SUSY phenomenology

33. Backup slide [Kran, Hansen, Nevski, hep-ph/0511014] Overview of SUSY phenomenology