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M.J. Ramsey-Musolf. Sub Z 0 Supersymmetry. Precision Electroweak Physics Below the Z 0 Pole. Fundamental Symmetries & Cosmic History. What were the fundamental symmetries that governed the microphysics of the early universe?.

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Sub z 0 supersymmetry

M.J. Ramsey-Musolf

Sub Z0 Supersymmetry

Precision Electroweak Physics Below the Z0 Pole


Fundamental symmetries cosmic history
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


Fundamental symmetries cosmic history1

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic History


Fundamental symmetries cosmic history2

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic History

It provides a unified framework for understanding 3 of the 4 (known) forces of nature in the present universe


Fundamental symmetries cosmic history3

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic History

It utilizes a simple and elegant symmetry principle

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


Fundamental symmetries cosmic history4

Strong (QCD)

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 History

It utilizes a simple and elegant symmetry principle

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


Fundamental symmetries cosmic history5

Electroweak

“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 History

It utilizes a simple and elegant symmetry principle

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


Fundamental symmetries cosmic history6

Atomic transitions & scattering

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic History

Most of its predictions have been confirmed

Parity violation in neutral current interactions


Fundamental symmetries cosmic history7

  • W, Z0 bosons

  • 3rd fermion generation (CP-violation)

  • Higgs boson (LHC ?)

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic History

Most of its predictions have been confirmed

New particles should be found

How is electroweak symmetry broken?


Fundamental symmetries cosmic history8

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic History

It gives a microscopic basis for understanding astrophysical observations


Fundamental symmetries cosmic history9

Unification & gravity

Weak scale stability

Origin of matter

Neutrino mass

Standard Model puzzles

Standard Model successes

Fundamental Symmetries & Cosmic History


We need a new standard model

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


Outline
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
I.Radiative Corrections & Precision Measurements in the SM



Fermi theory qed corrections
Fermi Theory: QED Corrections

QED radiative corrections: finite


Fermi theory s stumbling block higher order virtual weak effects
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


The standard model renormalizable control of virtual weak corrections

Re-define Weak Effectsg

Finite

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

g

g

g


G f encodes the effects of all higher order weak radiative corrections

g Weak Effects

g

GFencodes the effects of all higher order weak radiative corrections

Drm depends on parameters of particles inside loops


Comparing radiative corrections in different processes can probe particle spectrum

g Weak Effects

g

Comparingradiative corrections in different processes canprobeparticle spectrum

Drm differs fromDrZ


Comparing radiative corrections in different processes can probe particle spectrum1
Comparing Weak Effectsradiative corrections in different processes canprobeparticle spectrum


Comparing radiative corrections in different processes can probe particle spectrum2

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 spectrum

J. Ellison, UCI


Global analysis
Global Analysis Weak Effects

c2 per dof = 25.5 / 15

Agreement with SM at level of loop effects ~ 0.1%

M. Grunenwald


Ii why a new standard model
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


The early sm universe had no unification

Energy Scale ~ T Weak Effects

The early SM Universe had nounification

Couplings depend on scale


The early sm universe had no unification1

Present universe Weak Effects

Early universe

Standard Model

High energy desert

Weak scale

Planck scale

The early SM Universe had nounification


The early sm universe had no unification2

Present 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 nounification


The fermi constant is too large

Present 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 large


The fermi constant is too large1

m Weak EffectsWEAK ~ 250 GeV GF ~ 10-5/MP2

l

The Fermi constant is too large


A smaller g f a different cosmos

Smaller G Weak EffectsF More 4He, C, O…

A smaller GF,a different cosmos

The Sun would burn less brightly

G ~ GF2

Elemental abundances would change

Tfreeze out ~ GF-2/3


There is too little matter visible invisible in the sm universe

Measured abundances & WMAP Weak Effects

SM baryogenesis

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

Visible Matter from Big Bang Nucleosynthesis & CMB

Insufficient CP violation in SM


There is too little matter visible invisible in the sm universe1

No SM candidate Weak Effects

Dark

Insufficient SM CP violation

Visible

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

Invisible Matter

S. Perlmutter


There must have been additional symmetries in the earlier universe to

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 supersymmetry
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


Susy a candidate symmetry of the early universe

Fermions Weak Effects

Bosons

sfermions

gauginos

Higgsinos

Charginos, neutralinos

SUSY: a candidate symmetry of the early Universe

Supersymmetry


Susy and r parity
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


Couplings unify with susy

Present universe Weak Effects

Early universe

Standard Model

High energy desert

Weak scale

Planck scale

Couplings unify with SUSY

Supersymmetry


Susy protects g f from shrinking

=0 if SUSY is exact Weak Effects

SUSY protects GF from shrinking


Susy may help explain observed abundance of matter

c Weak Effects0 Lightest SUSY particle

CP Violation

Unbroken phase

Broken phase

SUSY may help explain observed abundance of matter

Cold Dark Matter Candidate

Baryonic matter: electroweak phase transition


Susy must be a broken symmetry

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


Iv low energy probes of susy

  • 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?

IV.Low Energy Probes of SUSY

  • J Erler (UNAM)

  • V Cirigliano (Caltech)

  • C Lee (INT)

  • S Su (Arizona)

  • S Tulin (Caltech)

  • S Profumo (Caltech)

  • A Kurylov


Precision low energy measurements can probe for new symmetries in the desert

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 desert


Weak decays

= Weak Effects

1

SM

Expt

Weak decays


Weak decays1

b Weak Effects-decay

SUSY Loops

Weak decays


Weak decays2

kaon decay Weak Effects

Value of Vusimportant

SUSY Loops: Too small

Weak decays


Weak decays susy

b Weak Effects-decay

SUSY loops

SUSY

Weak decays & SUSY


Susy radiative corrections

Vertex & External leg Weak Effects

Drm

SUSY Radiative Corrections

Propagator

Box


Weak decays susy1

Flavor-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 & SUSY


Sub z 0 supersymmetry

CKM Summary: PDG04 Weak Effects

UCNA


Sub z 0 supersymmetry

V Weak Effectsus & Vud theory ?

New 0+ info

CKM Summary: New Vus & tn ?

New tn !!

UCNA


Probing susy with lepton scattering

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

Probing SUSY with Lepton Scattering

Parity-Violating electron scattering


Probing susy with lepton scattering1

Cross section ratios Weak Effects

Probing SUSY with Lepton Scattering

Neutrino-nucleus deep inelastic scattering


Neutral currents mix

 Weak EffectsJmZ = Jm0 + 4 Q sin2WJmEM

SU(2)L

U(1)Y

Neutral currents mix

Weak mixing depends on scale


Weak mixing angle scale dependence

Atomic PV Weak Effects

N deep inelastic

sin2W

e+e- LEP, SLD

SLAC E158 (ee)

JLab Q-Weak (ep)

(GeV)

Weak Mixing Angle: Scale Dependence

Czarnecki, Marciano Erler, Kurylov, MR-M


Susy radiative corrections1

Vertex & External leg Weak Effects

SUSY Radiative Corrections

Propagator

Box


Comparing q w e and q w p

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 QWp

SUSY loops

Kurylov, Su, MR-M


Comparing q w e and q w p1

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 w e and q w p2
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.


Additional pv electron scattering ideas

Linear Weak EffectsCollider e-e-

Atomic PV

N deep inelastic

DIS-Parity, JLab

sin2W

e+e- LEP, SLD

SLAC E158 (ee)

JLab Q-Weak (ep)

Moller, JLab

(GeV)

Additional PV electron scattering ideas

Czarnecki, Marciano Erler et al.


What is the origin of baryonic matter

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

What is the origin of baryonic matter ?


Edm probes of 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 Violation


Sub z 0 supersymmetry

Better 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”


Edms baryogenesis

Present universe Weak Effects

Early universe

?

?

Weak scale (SUSY) baryogenesis can be tested experimentally

Weak scale

Planck scale

EDMs & Baryogenesis

Sakharov Criteria

  • B violation

  • C & CP violation

  • Nonequilibrium dynamics

Sakharov, 1967


Susy baryogenesis

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?

SUSY Baryogenesis

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

Unbroken phase

CP Violation


Edm constraints susy cpv

Near degeneracies resonances Weak Effects

BBN

WMAP

de

de

199Hg

199Hg

BAU

BAU

Lee et al

EDM constraints & SUSY CPV

Different choices for SUSY parameters


Edm constraints susy cpv1

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 CPV


Conclusions
Conclusions 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


Conclusions1
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