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Jan Kalinowski

SUSY 3. Jan Kalinowski. Outline. Linear Collider: why? Precision SUSY measurements at the ILC masses, couplings, mixing angles, CP phases, Towards reconstructing the fundamental theory the SPA Convention and Project Summary. After discovering SUSY at LHC. Sobloher. 200. 3000.

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Jan Kalinowski

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  1. SUSY 3 Jan Kalinowski

  2. Outline • Linear Collider: why? • Precision SUSY measurements at the ILC • masses, couplings, mixing angles, CP phases, • Towards reconstructing thefundamental theory • the SPA Convention and Project • Summary Supersymmetry, part 3

  3. After discovering SUSY at LHC Sobloher 200 3000 500 1000 • Many burning questions will arise: • is it really SUSY? (measurement of quantum numbers) • how is it realized? (MSSM, NMSSM, …) • how is it broken? • ILC will be indispensable to answer these questions! • Make full use of the flexibilityof the machine: • tunable energy • polarized beams • possibly e-e- and  collisions Supersymmetry, part 3

  4. The International Linear Collider An intense R&D process since 1992Huge world-wide effort to be ready for construction in 2009/10 (Global Design Effort GDE) ICFA parameter document: • The baseline: • - e+e- LC running from MZ to 500 GeV, tunable energy • - e- /e+ polarization • - at least 500 fb-1 in the first 4 years • Upgrade: to ~ 1 TeV 500 fb-1 /year • Options : • - GigaZ (high luminosity running at MZ) • , e, e-e- collisions • Choice of options depending on LHC+ILC physics results Supersymmetry, part 3

  5. The ILC physics case LHC + LC data analysed together  synergy! (LHC/ILC study group, `Weiglein et al.) • 0. Top quark at threshold • measure its mass, verify its couplings • 1. Higgs • ‘light’ (consistent with precision EW) • verify the Higgs mechanism is at work in all elements • ‘heavy’ (inconsistent with precision EW) •  find out why prec. EW data are inconsistent • 2. 1.+ new states (SUSY, ED, extra Z’, little H,...) • measurements of new states: masses, couplings • infer properties of states above kinematic limit • 3. No Higgs, no new states • find out why precision EW data are inconsistent • look for threshold effects of strong/delayed EWSB Supersymmetry, part 3

  6. Masses smuons: Martyn Two methods to obtain absolute sparticle masses: In the continuum At the kinematic threshold Supersymmetry, part 3

  7. Masses Berggren If a double cascade occurs, the intermediate state can be fully reconstructed e.g. • Assuming neutrino masses known to some extent • two LSP 4-momenta => 8 unknowns • 4 mass relations + E,p conservation => 8 constraints • LSP momenta can be reconstructed 4-momentum of the intermediate particle (here slepton) can be measured! So if you are used to think that a sparticle is just an edge or an end-point, change your mind – it can be a peak! Supersymmetry, part 3

  8. Couplings and mixings Freitas et al EW gauge and Yukawa couplings can be probed in e.g. Supersymmetry, part 3

  9. Charginos + neutralinos Desch, JK, Moortgat-Pick, Nojiri, Polesello Feeding info on m( ) back to ILC => improved accuracy Including masses and polarized cross sections for light neutralinos: Now ask your LHC friends to look for => crucial test of the model Supersymmetry, part 3

  10. Neutralino couplings In these analyses sleptons assumed to be seen at ILC and measured. What if all sfermons heavy, like in focus-point or split SUSY? Choi, JK, Moortgat-Pick, Zerwas also the equality of EW gauge and Yukawa couplings can be tested with polarized beams Supersymmetry, part 3

  11. Heavy sfermion case Focus-point inspired case Desch, JK, Moortgat-Pick, Rolbiecki, Stirling sfermions ~ 2 TeV only stop1 ~1.1 TeV • Expectations at LHC: • decay dominates, but huge background from top production • other squarks accessible, but low statistics, BG, .. => Dm=50 GeV • large gluino production, • dilepton edge clearly seen, measure • Expectations at ILC 500 GeV • large production, measure its mass precisely • very small cross section for neutralinos • masss from decay + LHC Supersymmetry, part 3

  12. Heavy sfermion case • obtain sneutrino mass • distinguish models • (e.g. focus point SUSY fromsplit SUSY) => AFB Decay lepton FB asymmetry Desch, JK, Moortgat-Pick, Rolbiecki, Stirling FB asymmetry very sensitive to sneutrino mass , Z Even a partial spectrum can tell a lot… Supersymmetry, part 3

  13. Majorana and CP of neutralinos Production: + Decay: If CP conserved, in non-relat. limit for production for decay ( intrinsic CP ) • Can be probed in • neutralino pair production at threshold • neutralino decay spectrum near the end-point • neutralino production decay after Fierz-ing selectron exchanges Supersymmetry, part 3

  14. Majorana and CP of neutralinos 1. Production at threshold • if => P-wave • if => S-wave CPC:if (12) and (13) in S-wave (23) must be in P-wave otherwise CP violated JK 2. Compare production of (12) with decay of 2->1 CPC:if production in S-wave decay must be in P-wave otherwise CP violated S.Y.Choi Supersymmetry, part 3

  15. eg and gg options Create HE photon beam by Compton back-scattering laser light on electrons Ginzburg, Kotkin, Serbo, Telnov Photons retain ~90% of electron beam energy almost 100% conversion – no loss of luminosity Supersymmetry, part 3

  16. eg example Illian, Monig ’05 N signal E (GeV) Assume that LSP mass=100 GeV and already measured => higher reach in selectron mass important SM background from can be considerably suppressed by taking right-handed electron beam Supersymmetry, part 3

  17. gg examples 2. Measure tanb (for moderate to large values) - important parameter - notoriuosly difficult to determine Choi, JK, Lee, Muhlleitner, Spira, Zerwas • very useful for Higgs boson studies • - higher kinematic reach • - investigate CP using polarized g beams Supersymmetry, part 3

  18. Cosmology connection: benchmarks How well <sv> can be predicted from LHC/ILC depends on model for NP American LCC + Snowmass05 benchmark points Peskin, LCWS06 Supersymmetry, part 3

  19. LCC2 J. Alexander et al. Need to know gaugino- higgsino mixing angle can be measured at ILC ILC resolves LHC alone allows multiple solutions Squarks and sleptons heavy, relevant param. M1, M2, tanb, m measured at LHC Supersymmetry, part 3

  20. LCC2: cross-checks, predictions • neutralino-proton cross section for • direct DM search experiments, • or using measured cross section • determine the flux of DM • rate of g from DM annihilation in • the galactic center, • or using measured rate determine • the DM density With the LSP properties determined, calculate Supersymmetry, part 3

  21. other LCC points The LHC will start testing cosmology. In some cases the LC will be invaluable. Supersymmetry, part 3

  22. Towards reconstructing SUSY: We would like to know the relation of the visible sector to the fundamental theory: • what is the origin of SUSY breaking ? • what is the role of neutrinos ? • is it related to the theory of early universe ? • how to embed gravity ? etc., etc. Probably we won’t have a direct experimental access to these questions But SUSY is a predictive framework ! We can analyse precision data and state how well within some specific SUSY/GUT model the relation of observable to fundamental physics can be established • Supersymmetry particles will be discovered at the LHC • Future ILC will provide additional precision data on masses and couplings Will everybody be happy? You may ask: who cares about precision ?? Supersymmetry, part 3

  23. Remember Tycho Brache ? from W. Kilian Supersymmetry, part 3

  24. Practical questions • What precision can be achieved on parameters of the MSSM Lagrangian ? • Lagrangian parameters not directly measurable • some parameters are not directly related to one particular observable, e.g., tanb, m • fitting procedure, .... • Can we reconsruct the fundamental theory at high scale ? • unification of couplings, soft masses etc.??? • which SUSY breaking mechanism ?? • How precisely can we predict masses, cross sections, branching ratos, couplings etc. ? • many relations between sparticle masses already at tree-level, much worse at loop-level • no obvious choice of renormalizaton scheme Goals of the SPA Project Supersymmetry, part 3

  25. http://spa.desy.de/spa • The SPA project is a joint study of theorists and experimentalists working on LHC and Linear Collider phenomenology. The study focuses on the supersymmetric extension of the Standard Model. The main targets are • High-precision determination of the supersymmetry Lagrange parameters at the electroweak scale • Extrapolation to a high scale to reconstruct the fundamental parameters and the mechanism for supersymmetry breaking • The SPA convention and the SPA Project are described in the SPA report, • Eur.Phys.J.C46:43-60,2006 [arXiv:hep-ph/05113444]. Spiritus movens: Peter Zerwas Supersymmetry, part 3

  26. The Document More than one ‘astronomer’ involved Please join in !!!! Supersymmetry, part 3

  27. Summa summarum • Supersymmetry has been motivated as a way to stabilize the hierarchy • At present: no sign, but not excluded either • If true, exciting times at near-future colliders • Precision measurements will be necessary to reconstruct the theory • Once seen and studied, it may provide a telescope to physics at GUT/Planck/string scales Supersymmetry, part 3

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