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## PowerPoint Slideshow about ' Sub Z 0 Supersymmetry' - nathaniel-cervantes

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### What is the origin of baryonic matter ?

Fundamental Symmetries & Cosmic History

- What were the fundamental symmetries that governed the microphysics of the early universe?

The (broken) symmetries of the Standard Model of particle physics work remarkably well at late times, but they leave many unsolved puzzles pertaining to the early universe

- What insights can low energy (E << MZ) precision electroweak studies provide?

New forces and their symmetries generally imply the existence of new particles. Looking for their footprints in low energy processes can yield important clues about their character

Standard Model successes

Fundamental Symmetries & Cosmic HistoryIt provides a unified framework for understanding 3 of the 4 (known) forces of nature in the present universe

Standard Model successes

Fundamental Symmetries & Cosmic HistoryIt utilizes a simple and elegant symmetry principle

SU(3)c x SU(2)L x U(1)Y

Scaling violations in DIS Asymptotic freedom R(e+e-) Heavy quark systems Drell-Yan

Chiral dynamics

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic HistoryIt utilizes a simple and elegant symmetry principle

SU(3)c x SU(2)L x U(1)Y

“Maximal” parity violation CP violation in K & B mesons Quark flavor mixing Lepton universality Conserved vector current

Radiative corrections

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic HistoryIt utilizes a simple and elegant symmetry principle

SU(3)c x SU(2)L x U(1)Y

Atomic transitions & scattering

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic HistoryMost of its predictions have been confirmed

Parity violation in neutral current interactions

- W, Z0 bosons
- 3rd fermion generation (CP-violation)
- Higgs boson (LHC ?)

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic HistoryMost of its predictions have been confirmed

New particles should be found

How is electroweak symmetry broken?

- Big Bang Nucleosynthesis (BBN) & light element abundances
- Weak interactions in stars & solar burning
- Supernovae & neutron stars

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic HistoryIt gives a microscopic basis for understanding astrophysical observations

Weak scale stability

Origin of matter

Neutrino mass

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic HistoryUltra cold neutrons

LANSCE, SNS, NIST

CERN

We need anew Standard ModelTwo 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

Outline

SM Radiative Corrections & Precision Measurements

Defects in the Standard Model

An Alternative: Supersymmetry

Low-energy Probes of Supersymmetry

New

I.Radiative Corrections & Precision Measurements in the SM

Fermi Theory: QED Corrections

QED radiative corrections: finite

Fermi Theory’s Stumbling Block: Higher Order (Virtual) Weak Effects

Weak radiative corrections: infinite

Can’t be absorbed through suitable re-definition of GFin HEFF

Re-define Weak Effectsg

Finite

The Standard Model (renormalizable): Control of Virtual Weak Correctionsg

g

g

g Weak Effects

g

GFencodes the effects of all higher order weak radiative correctionsDrm depends on parameters of particles inside loops

g Weak Effects

g

Comparingradiative corrections in different processes canprobeparticle spectrumDrm differs fromDrZ

Comparing Weak Effectsradiative corrections in different processes canprobeparticle spectrum

Probing Fundamental Symmetries beyond the SM: Weak Effects

Use precision low-energy measurements to probe virtual effects of new symmetries & compare with collider results

- 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 spectrumJ. Ellison, UCI

Global Analysis Weak Effects

c2 per dof = 25.5 / 15

Agreement with SM at level of loop effects ~ 0.1%

M. Grunenwald

II. Weak EffectsWhy 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

Present universe Weak Effects

Early universe

Standard Model

High energy desert

Weak scale

Planck scale

The early SM Universe had nounificationPresent universe Weak Effects

Early universe

Standard Model

Gravity

A “near miss” for grand unification

Is there unification? What new forces are responsible ?

High energy desert

Weak scale

Planck scale

The early SM Universe had nounificationPresent universe Weak Effects

Early universe

Unification Neutrino mass Origin of matter

Standard Model

Weak scale unstable:

Why is GF so large?

High energy desert

Weak scale

Planck scale

The Fermi constant is too largeSmaller G Weak EffectsF More 4He, C, O…

A smaller GF,a different cosmosThe Sun would burn less brightly

G ~ GF2

Elemental abundances would change

Tfreeze out ~ GF-2/3

Measured abundances & WMAP Weak Effects

SM baryogenesis

There is too little matter -visible & invisible - in the SM UniverseVisible Matter from Big Bang Nucleosynthesis & CMB

Insufficient CP violation in SM

No SM candidate Weak Effects

Dark

Insufficient SM CP violation

Visible

There is too little matter -visible & invisible - in the SM UniverseInvisible Matter

S. Perlmutter

Supersymmetry, GUT’s, extra dimensions… Weak Effects

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

III. Weak EffectsSupersymmetry

- 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

Fermions Weak Effects

Bosons

sfermions

gauginos

Higgsinos

Charginos, neutralinos

SUSY: a candidate symmetry of the early UniverseSupersymmetry

SUSY and R Parity Weak Effects

If nature conserves

vertices have even number of superpartners

- Lightest SUSY particle

is stable

viable dark matter candidate

- Proton is stable

- Superpartners appear only in loops

Consequences

Present universe Weak Effects

Early universe

Standard Model

High energy desert

Weak scale

Planck scale

Couplings unify with SUSYSupersymmetry

=0 if SUSY is exact Weak Effects

SUSY protects GF from shrinkingc Weak Effects0 Lightest SUSY particle

CP Violation

Unbroken phase

Broken phase

SUSY may help explain observed abundance of matterCold Dark Matter Candidate

Baryonic matter: electroweak phase transition

SUSY Breaking Weak Effects

Superpartners have not been seen

Theoretical models of SUSY breaking

Visible World

Hidden World

Flavor-blind mediation

Can we test models of SUSY breaking mediation ?

SUSY must be a broken symmetry- How is SUSY broken? Weak Effects
- How viable is SUSY dark matter ?
- Is there enough SUSY CP violation to account for the matter-antimatter asymmetry?

- J Erler (UNAM)
- V Cirigliano (Caltech)
- C Lee (INT)
- S Su (Arizona)
- S Tulin (Caltech)
- S Profumo (Caltech)
- A Kurylov

Precision ~ Mass Scale Weak Effects

Interpretability

- Precise, reliable SM predictions
- Comparison of a variety of observables
- Special cases: SM-forbidden or suppressed processes

M=m~ 2 x 10-9

exp ~ 1 x 10-9

M=MW ~ 10-3

Precision, low energy measurements can probe for new symmetries in the desertFlavor-blind SUSY-breaking Weak Effects

12k

R ParityViolation

Kurylov, R-M, Su

CKM Unitarity

MW

CKM, (g-2)m, MW, Mt ,…

APV

l2

b-decay

12k

1j1

1j1

No long-lived LSP or SUSY DM

SUSY loops

Kurylov, R-M

RPV

SUSY

Weak decays & SUSYCKM Summary: PDG04 Weak Effects

UCNA

“Weak Charge” ~ 1 - 4 sin Weak Effects2 qW ~ 0.1

Probing SUSY with Lepton ScatteringParity-Violating electron scattering

Cross section ratios Weak Effects

Probing SUSY with Lepton ScatteringNeutrino-nucleus deep inelastic scattering

Weak EffectsJmZ = Jm0 + 4 Q sin2WJmEM

SU(2)L

U(1)Y

Neutral currents mixWeak mixing depends on scale

Atomic PV Weak Effects

N deep inelastic

sin2W

e+e- LEP, SLD

SLAC E158 (ee)

JLab Q-Weak (ep)

(GeV)

Weak Mixing Angle: Scale DependenceCzarnecki, Marciano Erler, Kurylov, MR-M

What about RPV ? Weak Effects

105 parameters: random scan

SUSY loops

3000 randomly chosen SUSY parameters but effects are correlated

Effects insin2qWdominate

Negligible SUSY loop impact on cesium weak charge

Comparing Qwe and QWpSUSY loops

Kurylov, Su, MR-M

n Weak Effects is Majorana

SUSY loops

RPV 95% CL fit to weak decays, MW, etc.

Comparing Qwe and QWp SUSY dark matter

->e+e

Kurylov, Su, MR-M

Comparing Q Weak Effectswe and QWp

- Can be a diagnostic tool to determine whether or not
- the early Universe was supersymmetric
- there is supersymmetricdark matter

The weak charges can serve a similar diagnostic purpose for other models for high energy symmetries, such as left-right symmetry, grand unified theories with extra U(1) groups, etc.

Linear Weak EffectsCollider e-e-

Atomic PV

N deep inelastic

DIS-Parity, JLab

sin2W

e+e- LEP, SLD

SLAC E158 (ee)

JLab Q-Weak (ep)

Moller, JLab

(GeV)

Additional PV electron scattering ideasCzarnecki, Marciano Erler et al.

Cosmic Energy Budget Weak Effects

Dark Matter

Dark Energy

T-odd , CP-odd by CPT theorem

Baryons

Searches for permanent electric dipole moments (EDMs) of the neutron, electron, and neutral atoms probe SUSY CP-violation

CKM Weak Effects

fdSM dexp dfuture

Also 225Ra, 129Xe, d

If new EWK CP violation is responsible for abundance of matter, will these experiments see an EDM?

EDM Probes of SUSY CP ViolationBetter theory Weak Effects

Present n-EDM limit

Proposed n-EDM limit

Matter-Antimatter

Asymmetry in

the Universe

?

M. Pendlebury B. Filippone

Riotto; Carena et al.; Lee, Cirigliano, R-M, Tulin

“n-EDM has killed more theories than any other single experiment”

Present universe Weak Effects

Early universe

?

?

Weak scale (SUSY) baryogenesis can be tested experimentally

Weak scale

Planck scale

EDMs & BaryogenesisSakharov Criteria

- B violation
- C & CP violation
- Nonequilibrium dynamics

Sakharov, 1967

Weak Scale Baryogenesis Weak Effects

- B violation
- C & CP violation
- Nonequilibrium dynamics

Topological transitions

Broken phase

1st order phase transition

Sakharov, 1967

- Is it viable?
- Can experiment constrain it?
- How reliably can we compute it?

90’s: Cohen, Kaplan, NelsonJoyce, Prokopec, Turok

Unbroken phase

CP Violation

Near degeneracies resonances Weak Effects

BBN

WMAP

de

de

199Hg

199Hg

BAU

BAU

Lee et al

EDM constraints & SUSY CPVDifferent choices for SUSY parameters

Dark Matter Constraints Weak Effects

Future: EDMs & LHC

de

dn

BBN

WMAP

BAU-DM

Lee et al

Large Hadron Collider

Large Hadron Collider

Cirigliano, Profumo, MR-M in preparation

EDM constraints & SUSY CPVConclusions Weak Effects

- The Standard Model is triumph of 20th century physics, but we know it is far from a complete theory

Lack of unification, size of the Fermi constant, abundance of matter, neutrino mass, gravity,…

- Supersymmetry is a leading candidate theory that might address many of these SM shortcomings

Future high-energy collider experiments may discover it

- Precision measurements in particle, nuclear, and atomic physics at energies below MZcan provide important indirect information about what form of SUSY - if any - is viable

Weak decays, lepton scattering, electric dipole moments

Conclusions Weak Effects

- The interface between high-energy collider physics and precision low-energy physics involves a rich and stimulating “synergy” between many sub-fields of physics

Sub-Z0 : A working group on precision electroweak physics below the Z-pole

http://krl.caltech.edu/~subZ

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