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Sub Z Supersymmetry

M.J. Ramsey-Musolf. Sub Z Supersymmetry. Precision Electroweak Studies in Nuclear Physics. NSAC Long Range Plan. What is the structure of the nucleon? What is the structure of nucleonic matter? What are the properties of hot nuclear matter? What is the nuclear microphysics of the universe?

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Sub Z Supersymmetry

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  1. M.J. Ramsey-Musolf Sub Z Supersymmetry Precision Electroweak Studies in Nuclear Physics

  2. NSAC Long Range Plan • What is the structure of the nucleon? • What is the structure of nucleonic matter? • What are the properties of hot nuclear matter? • What is the nuclear microphysics of the universe? • What is to be the new Standard Model? Neutrino physics Precision measurements: -decay, -decay, parity violating electron scattering, EDM’s… What can they teach us about the new Standard Model?

  3. TheStandard Modelof particle physics is a triumph of late 20th century physics • It provides a unified framework for 3 of 4 (known) forces of nature in context of renormalizable gauge theory

  4. TheStandard Modelof particle physics is a triumph of late 20th century physics • Utilizes a simple & elegant symmetry principle to organize what we’ve observed

  5. TheStandard Modelof particle physics is a triumph of late 20th century physics • Utilizes a simple & elegant symmetry principle to organize what we’ve observed Scaling violations in DIS Asymptotic freedom R(e+e-) Heavy quark systems Drell-Yan Strong (QCD)

  6. TheStandard Modelof particle physics is a triumph of late 20th century physics • Utilizes a simple & elegant symmetry principle to organize what we’ve observed “Maximal” parity violation Conserved Vector Current CP-Violation in K, B mesons Quark flavor mixing Lepton universality….. Electroweak (=weak + QED)

  7. TheStandard Modelof particle physics is a triumph of late 20th century physics • Most of its predictions have been confirmed Parity violation in neutral current processes: deep inelastic scattering, atomic transitions

  8. sin2qW The Standard Modelof particle physics is a triumph of late 20th century physics • Most of its predictions have been confirmed Jl0 Jlg JlY JlZ Neutral currents mix

  9. Not yet! TheStandard Modelof particle physics is a triumph of late 20th century physics • Most of its predictions have been confirmed • W, Z0 • 3rd fermion generation (CP violation, anomaly) • Higgs boson New particles should be found

  10. Large Hadron Collider Ultra cold neutrons LANSCE, SNS, NIST CERN We need anew Standard Model Two frontiers in the search Collider experiments (pp, e+e-, etc) at higher energies (E >> MZ) Indirect searches at lower energies (E < MZ) but high precision Particle, nuclear & atomic physics High energy physics

  11. Precision measurements • “Forbidden processes” • Weak decays • lepton scattering Outline SM Radiative Corrections & Precision Measurements Defects in the Standard Model An Example Scenario: Supersymmetry Low-energy Probes of Supersymmetry

  12. Precision measurements • “Forbidden processes” • EDM’s • 0nbb decay • m !e, m !eg… Outline SM Radiative Corrections & Precision Measurements Defects in the Standard Model An Example Scenario: Supersymmetry Low-energy Probes of Supersymmetry

  13. I.Radiative Corrections & Precision Measurements in the SM

  14. TheFermi Theoryof weak decays gave a successful, leading-order account

  15. Fermi’s theory could incorporatehigher order QED contributions QED radiative corrections: finite

  16. The Fermi theory has trouble withhigher order weak contributions Weak radiative corrections: infinite Can’t be absorbed through suitable re-definition of GFin HEFF

  17. Re-define g Finite All radiative corrections can be incorporated in the Standard Model with afinitenumber of terms g g g

  18. g g GFencodes the effects of all higher orderweak radiative corrections Drm depends on parameters of particles inside loops

  19. g g Comparingradiative corrections in different processes canprobeparticle spectrum Drm differs from DrZ

  20. Comparingradiative corrections in different processes canprobeparticle spectrum

  21. Precision measurements predicted a range for mt before top quark discovery • mt >> mb ! • mt is consistent with that range • It didn’t have to be that way Radiative corrections Direct Measurements Stunning SM Success Comparingradiative corrections in different processes canprobeparticle spectrum J. Ellison, UCI

  22. Agreement with SM at level of loop effects ~ 0.1% Global Analysis c2 per dof = 25.5 / 15 M. Grunenwald

  23. LEP SLD Tevatron Collider Studies R. Clare, UCR

  24. Collider Studies

  25. MW Mt Am shad Collider Studies Tevatron

  26. Collider Studies

  27. Collider Studies

  28. “Blue Band” Collider Studies

  29. c2 per dof = 16.3 / 13 Global Fit: Winter 2004

  30. II.Why a “New Standard Model”? • There is no unification in the early SM Universe • The Fermi constant is inexplicably large • There shouldn’t be this much visible matter • There shouldn’t be this much invisible matter

  31. Energy Scale ~ T The early SM Universe had nounification Couplings depend on scale

  32. Present universe Early universe Standard Model High energy desert Weak scale Planck scale The early SM Universe had nounification

  33. Present universe Early universe Standard Model Gravity A “near miss” for grand unification High energy desert Weak scale Planck scale The early SM Universe had nounification

  34. Present universe Early universe Unification Neutrino mass Dark Matter Standard Model GF would shrink High energy desert Weak scale Planck scale The Fermi constant is too large

  35. mWEAK ~ 250 GeV GF ~ 10-5/MP2 l The Fermi constant is too large

  36. Smaller GF More 4He, C, O… A smaller GF would mean disaster The Sun would burn less brightly G ~ GF2 Elemental abundances would change Tfreeze out ~ GF-2/3

  37. Measured abundances SM baryogenesis There is too much matter -visible & invisible - in the SM Universe Visible Matter from Big Bang Nucleosynthesis Insufficient CP violation in SM

  38. No SM candidate Dark Insufficient SM CP violation Visible There is too much matter -visible & invisible - in the SM Universe Invisible Matter S. Perlmutter

  39. There must have been additional symmetries in the earlier Universe to • Unify all forces • Protect GF from shrinking • Produce all the matter that exists • Account for neutrino properties • Give self-consistent quantum gravity

  40. III.Supersymmetry • Unify all forces • Protect GF from shrinking • Produce all the matter that exists 3 of 4 Yes Maybe so • Account for neutrino properties • Give self-consistent quantum gravity Maybe Probably necessary

  41. Fermions Bosons sfermions gauginos Higgsinos Charginos, neutralinos SUSY may be one of the symmetries of the early Universe Supersymmetry

  42. Present universe Early universe Standard Model High energy desert Weak scale Planck scale Couplings unify with SUSY Supersymmetry

  43. =0 if SUSY is exact SUSY protectsGFfrom shrinking

  44. c0 Lightest SUSY particle CP Violation Unbroken phase Broken phase SUSY may help explain observed abundance of matter Cold Dark Matter Candidate Baryonic matter

  45. SUSY Breaking Superpartners have not been seen Theoretical models of SUSY breaking Visible World Hidden World Flavor-blind mediation SUSY must be a broken symmetry

  46. LSM LSM + LSUSY + Lsoft Minimal Supersymmetric Standard Model (MSSM) Lsoft gives contains 105 new parameters How is SUSY broken?

  47. Visible Sector: Hidden Sector: SUSY-breaking MSSM Flavor-blind mediation How is SUSY broken? Gravity-Mediated (mSUGRA)

  48. Visible Sector: Hidden Sector: SUSY-breaking MSSM messengers How is SUSY broken? Flavor-blind mediation Gauge-Mediated (GMSB)

  49. ln gaugino mass group structure increases as decreases increases faster than at the weak scale Mass evolution

  50. Qf < 0 Qf > 0 Sfermion Mixing

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