Supersymmetry!

The Cosmos …

Time

Space … and the LHC

John ELLIS, CERN, Geneva, Switzerland 300,000 Formation years of atoms

3 Formation minutes of nuclei

Formation 1 micro- of protons second & neutrons Origin of dark matter? 1 pico- Appearance second of mass? Origin of Matter? A Strange Recipe for a Universe

Ordinary Matter

The ‘Concordance Model’ prompted by astrophysics & cosmology Open Cosmological Questions

• Where did the matter come from? LHC? 1 proton for every 1,000,000,000 photons • What is the dark matter? LHC? Much more than the normal matter • What is the dark energy? LHC? Even more than the dark matter • Why is the Universe so big and old? LHC? Mechanism for cosmological inflation

Need particle physics to answer these questions The Very Early Universe

• Size: a  zero • Age: t  zero • Temperature: T  large T ~ 1/a, t ~ 1/T2 • Energies: E ~ T • Rough magnitudes: T ~ 10,000,000,000 degrees E ~ 1 MeV ~ mass of electron t ~ 1 second

Need particle physics to describe earlier history DarkDark MatterMatter in in the the Universe Universe

Astronomers say thatAstronomers most of tellthe matterus that mostin the of the Universematter in theis invisibleuniverse is Darkinvisible Matter „Supersymmetric‟ particles ? WeWe shallwill look look for for it themwith thewith LHC the LHC Where does the Matter come from?

Dirac predicted the existence of antimatter: same mass opposite internal properties: electric charge, … Discovered in cosmic rays Studied using accelerators

Matter and antimatter not quite equal and opposite: WHY?

2008 Nobel Physics Prize: Kobayashi & Maskawa Is this why the Universe contains mainly matter, not antimatter?

Need physics beyond the Standard Model: objective of the LHC How to Create the Matter in the Universe? Sakharov • Need a difference between matter and antimatter observed in the laboratory • Need interactions that make matter present in unified theories not yet seen by experiment • Must break thermal equilibrium Possible in the early Universe

Will we be able to calculate using laboratory data? Summary of the Standard Model

• Particles and SU(3) × SU(2) × U(1) quantum numbers:

• Lagrangian: gauge interactions matter fermions Yukawa interactions Higgs potential Parameters of the Standard Model

• Gauge sector:

– 3 gauge couplings: g3, g2, g ́ Unification? – 1 strong CP-violating phase • Yukawa interactions: – 3 charge-lepton masses Flavour? – 6 quark masses – 4 CKM angles and phase • Higgs sector: – 2 parameters: μ, λ Mass? • Total: 19 parameters Status of the Standard Model

• Perfect agreement with all confirmed accelerator data • Consistency with precision electroweak data (LEP et al) only if there is a Higgs boson • Agreement seems to require a relatively light Higgs boson weighing < ~ 180 GeV • Raises many unanswered questions: mass? flavour? unification? Precision Tests of the Standard Model

Lepton couplings Pulls in global fit Open Questions beyond the Standard Model • What is the origin of particle masses? LHC due to a Higgs boson? • Why so many types of matter particles? LHC • What is the dark matter in the Universe? LHC • Unification of fundamental forces? LHC • Quantum theory of gravity? LHC Why do Things Weigh? Newton: Weight proportional to Mass

Einstein: Energy related to Mass

Neither explained0 origin of Mass Where do the masses come from? Are masses due to Higgs boson? (the physicists‟ Holy Grail) 2008 Nobel Physics Prize: Nambu Think of a Snowfield

Skier moves fast: Like particle without mass e.g., photon = particle of light Snowshoer sinks into snow, moves slower: Like particle with mass e.g., electron The LHC will look for Hiker sinks deep, the snowflake: moves very slowly: The Higgs Boson Particle with large mass The State of the Higgs: May 2009

• Direct search limit from LEP:

mH > 114.4 GeV

• Electroweak fit sensitive to mt

(Now mt = 173.1 ± 1.3 GeV) • Best-fit value for Higgs mass: +34 mH = 84 –26 GeV • 95% confidence-level upper limit:

mH < 154 GeV, or 185 GeV including direct limit • Tevatron exclusion:

mH < 160 GeV or > 170 GeV Higgs Search @ Tevatron

Tevatron excludes Higgs between 160 & 170 GeV Combining the Higgs Information

+ 15.6 mH = 116.4 -1.3 GeV Supersymmetry?

• Would unify matter particles and force particles • Related particles spinning at different rates 0 - ½ - 1 - 3/2 - 2 Higgs - Electron - Photon - Gravitino - Graviton (Every particle is a „ballet dancer‟) • Would help fix particle masses • Would help unify forces • Predicts light Higgs boson • Could provide dark matter for the astrophysicists and cosmologists Unify the Fundamental Interactions: Einstein‟s Dream …

 … but he never succeeded

Maybe with extra dimensions of space? At what Energy is the New Physics?

Dark matter

Origin of mass

A lot accessible Some accessible only via to the LHC astrophysics & cosmology To answer these questions: The Large Hadron Collider (LHC)

Several thousand billion protons Each with the energy of a fly Primary targets: •Origin of mass 99.9999991% of light speed •Nature of Dark Matter Orbit 27km ring 11 000 times/second •Primordial Plasma A billion collisions a second •Matter vs Antimatter The Emptiest Space in the Solar System

Vacuum similar to interplanetary space: the pressure in the beam-pipes will be ten times lower than on the Moon. Colder than Outer Space

LHC 1.9 degrees above absolute zero = - 271 C Outer space 2.7 degrees above zero = - 270 C First Beam on Sept. 10th

A billion people watched on TV Temporary Halt since Sept. 19th

• Electrical fault in connection between two magnets • Ohmic heating broke cryostat, vacuum pipe • Repairs ongoing during shutdown • Precursor diagnostic identified • Simple rewiring to avoid recurrence • Relief valves being installed Last repaired Magnet being lowered Pressure Release Valves Residual potential Concern Safe operating Conditions GeneralVista General View delof LHC y& sus itsExperimentos Experiments

27km in circumference ~ 100m deep ALICE: Primordial cosmic plasma ATLAS: Higgs and supersymmetry

CMS: Higgs and supersymmetry LHCb: Matter-antimatter difference The ATLAS Detector

Diameter 25 m Over 2000 scientists and engineers Total length 46 m Nearly 40 countries Overall weight 7000 tons More components than a moon rocket Assembling ATLAS The CMS detector: search for Higgs and supersymmetry

Heavier than the Eiffel Tower: would sink in water

2500 physicists 180 institutes 37 countries Construction of CMS The LHC Physics Haystack(s)

Interesting cross sections • Cross sections for heavy particles ~ 1 /(1 TeV)2 • Most have small couplings ~ α2 • Compare with total cross section ~ 1/(100 MeV)2 • Fraction ~ 1/1,000,000,000,000

Susy • Need ~ 1,000 events for signal • Compare needle ~ 1/100,000,000 m3 Higgs • Haystack ~ 100 m3 • Must look in ~ 100,000 haystacks A Simulated Higgs Event A la recherche du Some Sample Higgs Signals Higgs perdu …

γγ

ZZ* -> 4 leptons ττ When will the LHC discover the Higgs boson?

1 „year‟ @ 1033

„month‟ @ 1033

„month‟ @ 1032

Blaising, JE et al: 2006 Theoretical Constraints on Higgs Mass

• Large → large self-coupling → blow up at low energy scale Λ due to renormalization • Small: renormalization due to t quark drives quartic coupling < 0 at some scale Λ → vacuum unstable • Bounds on Higgs mass depend on Λ Vacuum Stability vs Metastability

• Dependence on scale up to which Standard Model remains – Stable – Metastable at non-zero temperature – Metastable at zero temperature What is the probable fate of the SM?

Confidence Levels (CL) Confidence Levels (CL) for different fates without/with Tevatron exclusion

Blow-up excluded at 99.2% CL

CL as function of instability scale  Espinosa, JE, Giudice, Hoecker, Riotto The LHC will tell the fate of the SM

Examples with LHC measurement of mH = 120 or 115 GeV

Espinosa, JE, Giudice, Hoecker, Riotto How to Stabilize a Light Higgs Boson?

• Top quark destabilizes potential: introduce introduce stop-like scalar:

• Can delay collapse of potential: • But new coupling must be fine-tuned to avoid blow-up: • Stabilize with new fermions: – just like Higgsinos • Very like Supersymmetry!

JE & D. Ross The Stakes in the Higgs Search

• How is particle symmetry broken? • Is there an elementary scalar field? • What is the fate of the Standard Model? • Did mass appear when the Universe was a picosecond old? • Did Higgs help create the matter in the Universe? • Did a related inflaton make the Universe so big and old? • Why is there so little dark energy? Comments on Dark Energy

• Many orders of magnitude smaller than expected contributions from „known‟ physics: 10-48 GeV4 4 -4 4 QCD: ΛQCD ~ 10 GeV 4 8 4 Higgs: mW ~ 10 GeV 4 12 4 Broken susy: msusy ~ 10 GeV 4 64 4 GUT: mGUT ~ 10 GeV 4 76 4 Quantum Gravity: mP ~ 10 GeV • Need new physics! The Higgs and Vacuum Energy

• Must add a constant to the effective potential so that net value in true vacuum ~ 0 • Physical value ~ 10-60 • Will light be cast by discovery of Higgs? Theorists getting Cold Feet

• Composite Higgs model? conflicts with precision electroweak data • Interpretation of EW data? consistency of measurements? Discard some? • Higgs + higher-dimensional operators? corridors to higher Higgs masses? • Little Higgs models? extra „Top‟, gauge bosons, „Higgses‟ • Higgsless models? strong WW scattering, extra D? Elementary Higgs or Composite?

• Higgs field: • Fermion-antifermion <0|H|0> ≠ 0 condensate • Quantum loop problems • Just like QCD, BCS Cutoff superconductivity Λ = 10 TeV • Top-antitop condensate?

needed mt > 200 GeV • New technicolour force? inconsistent with • Cut-off Λ ~ 1 TeV precision electroweak data? with Supersymmetry? Supersymmetry?

• Consider generic fermion and boson loops:

• Each is quadratically divergent: ∫Λd4k/k2 2

• Leading divergence cancelled if x 2 Supersymmetry! Other Reasons to like Susy

It enables the gauge couplings to unify

It predicts mH < 150 GeV

JE,As Nanopoulos, suggested Olive +by Santoso: electroweak hep-ph/0509331 data Lightest Supersymmetric Particle

• Stable in many models because of conservation of R parity: Fayet R = (-1) 2S –L + 3B where S = spin, L = lepton #, B = baryon # • Particles have R = +1, sparticles R = -1: Sparticles produced in pairs Heavier sparticles  lighter sparticles • Lightest supersymmetric particle (LSP) stable Possible Nature of LSP

• No strong or electromagnetic interactions Otherwise would bind to matter Detectable as anomalous heavy nucleus • Possible weakly-interacting scandidates Sneutrino (Excluded by LEP, direct searches) Lightest neutralino χ (partner of Z, H, γ) Gravitino (nightmare for astrophysical detection) Constraints on Supersymmetry

• Absence of sparticles at LEP, Tevatron selectron, chargino > 100 GeV squarks, gluino > 300 GeV • Indirect constraints 3.3 σ effect in

Higgs > 114 GeV, b → s γ gμ – 2? • Density of dark matter lightest sparticle χ: 2 0.094 < Ωχh < 0.124 Quo Vadis

g -2? • Older e+e-data show discrepancy – now 3.4  • Disagreement with decay data – discrepancy ~ 2  • Look for new data from BABAR experiment Minimal Supersymmetric Extension of Standard Model (MSSM) • Particles + spartners

• 2 Higgs doublets, coupling μ, ratio of v.e.v.‟s = tan β • Unknown supersymmetry-breaking parameters:

Scalar masses m0, gaugino masses m1/2, trilinear soft couplings Aλ, bilinear soft coupling Bμ • Assume universality? constrained MSSM = CMSSM

Single m0, single m1/2, single Aλ, Bμ: not string? • Not the same as minimal supergravity (mSUGRA) • Gravitino mass, additional relations

m3/2 = m0, Bμ = Aλ – m0 Current Constraints on CMSSM

Assuming the lightest sparticle is a neutralino

Excluded because stau LSP

Excluded by b  s gamma

WMAP constraint on relic density

Preferred (?) by latest g - 2

JE + Olive + Santoso + Spanos Current Constraints Different tan β on sign of μ CMSSM

Impact of Higgs constraint reduced

if larger mt Focus-point region far up JE + Olive + Santoso + Spanos Supersymmetric Parameter Space

Lines in susy space allowed Specific benchmark points by accelerators, WMAP data along WMAP lines

Battaglia, De Roeck, Gianotti, JE, Olive, Pape Looking for Dark Matter @ LHC

Missing energy taken away by dark matter particles How Soon Might the CMSSM be Detected?

O.Buchmueller, JE et al: arXiv:0808.4128 CMSSM with 1/fb of LHC Data

O.Buchmueller et al Best-Fit Spectra

CMSSM NUHM1

O.Buchmueller, JE et al: arXiv:0808.4128 Likelihood Function for Neutralino Mass

CMSSM NUHM1

O.Buchmueller, JE et al: in preparation Sensitivities to Constraints

g - 2 b  s 

O.Buchmueller et al (In)Sensitivity to WMAP

O.Buchmueller et al Strategies for Detecting Supersymmetric Dark Matter

• Annihilation in galactic halo χ – χ  antiprotons, positrons, …? • Annihilation in galactic centre χ – χ  γ + …? • Annihilation in core of Sun or Earth χ – χ  ν + …  μ + … • Scattering on nucleus in laboratory χ + A  χ + A Elastic Scattering Cross Sections

CMSSM NUHM1

O.Buchmueller, JE et al: in preparation Likelihood Function for Spin- Independent Dark Matter Cross Section

CMSSM NUHM1

O.Buchmueller, JE et al: in preparation Annihilation in Galactic Halo

Antiprotons Positrons Cosmic-ray background

Consistent with production by Benchmark scenarios primary matter cosmic rays JE + Feng + Ferstl + Matchev + Olive Annihilations in Galactic Centre

Benchmark spectra Benchmarks  GLAST

Enhancement of rate uncertain by factor > 100!

JE + Feng + Ferstl + Matchev + Olive Annihilations in Solar System …

… Sun … Earth

Prospective experimental sensitivities Benchmark scenarios

JE + Feng + Ferstl + Matchev + Olive Long-lived Supersymmetric Particle

• Inevitable in many models – because gravitino has gravitation-strength interactions ~ 1/MP • If neutralino is LSP: – Gravitino is long-lived • If gravitino is LSP – Next-to-lightest sparticle (NLSP) is long-lived • Constrained by possible effects on light- element abundances Making Elements in the Early Universe

• Universe contains about 24% Helium 4 and less Deuterium, Helium 3, Lithium 7 • Could only have been cooked by nuclear reactions in dense early Universe when Universe billion times smaller, hotter than today • Dependent on amount of matter in Universe not enough to stop expansion, explain galaxies • Dependent on number of particle types number of different neutrinos measured at accelerators Abundances of light elements in the Universe

Helium  Agree with data

Assuming 3 neutrino species 

Theoretical calculations 

Lithium

Possible problem with abundance of 7Li

Not enough ordinary matter to make the Universe recollapse Gravitino Lifetime in CMSSM

• Lifetimes along WMAP strip for different m3/2

Cyburt + JE + Fields + Luo + Olive Hadronic Components of Showers Produced by Decays • Electromagnetic and hadronic components of

showers affect light-element abundances Nucleons per decay per Nucleons

Cyburt + JE + Fields + Luo + Olive Light-Element Abundances

• Deuterium abundance agrees with calculations:

• Upper limit on primordial 3He abundance:

• 4He abundance agrees with calculations:

• 7Li abundance less than predicted:

Cyburt + JE + Fields + Luo + Olive Constraints from Light-Element Abundances

No way to fix 7Li problem

Cyburt + JE + Fields + Luo + Olive The Stakes in the SUSY Search

• A novel symmetry of Nature? • Circumstantial hint for string theory? • Stabilize the hierarchy of mass scales in physics? • Explain 90% of the matter in the Universe? • Leads to unification of the fundamental forces? The Present Electroweak Vacuum may well be Unstable • Within the Standard Model: – If Higgs boson is light • Stabilize vacuum with physics beyond the SM? – Supersymmetry a natural choice • But vacuum unstable in favoured models of supersymmetry breaking – May also be unstable in supergravity/string • The LHC will provide insight: – Measure Higgs and/or sparticle masses The Possible fate of the Vacuum

Our vacuum may decay after billions of years LHC cannot trigger vacuum decay But it may give us advance warning Abel, JE, Jaeckel and Khoze Is our Vacuum Unstable?

Many supersymmetric scenarios also have unstable vacua

Abel, JE, Jaeckel and Khoze Vacuum Instability in the CMSSM

Region allowed if fields initially at/near origin, non- JE, Giedt, Lebedev, Olive & Srednicki n renormalizable 1/MX terms in potential, gravitino LSP But, in the Immortal Words of an Anonymous Referee …

“It is certainly not one of the key initial issues the LHC will explore, or that physicists more broadly will care about” How large could extra Dimensions be?

• 1/TeV? could break supersymmetry, electroweak • micron? can rewrite hierarchy problem • Infinite? warped compactifications • Look for black holes, Kaluza-Klein excitations @ colliders? And if gravity becomes strong at the TeV scale … Black Hole Production at LHC?

Decays via Hawking radiation The LHCb Experiment: Explore Matter and Antimatter Minimal Flavour Violation (MFV) & Maximal CP Violation (MCP) • All squark mixing due to CKM matrix • Universal scalar masses at high scale for sparticles with same quantum numbers • Parametrization:

• Maximally CP-violating MFV (MCPMFV) model has 19 parameters, of which 6 violate CP:

• Often assume universal ImMa, ImAf, but non- universality compatible with MFV: MCPMFV JE, Lee & Pilaftsis CPV Asymmetries in Sparticle Decays?

Consider stop cascade decays:

three T-odd asymmetries

JE, Moortgat, Moortgat-Pich, Smillie & Tattersall, arXiv:0809.1607 SUSY Electroweak Baryogenesis?

• Exploit phases in SUSY MCPMFV model • Require light stop for first-order electroweak transition • Higgs and stop masses tightly constrained by theory and experiment

Carena, Nardini, Quiros and Wagner: arXiv:0809.3760 The ALICE Detector Collide heavy nuclei at high energies to create … Hot and Dense Hadronic Matter Properties described by Recreate the first 10-6 seconds … AdS/CFT correspondence: Viscosity, jet quenching, …? … and probe the quark-hadron phase transition Hot and Dense Hadronic Matter

Recreate the first 10-6 seconds … … and probe the quark-hadron phase transition LHC

LHC The LHC is not only the World‟s most powerful microscope, but also a telescope …

… able to cast light on the dark corners of the Universe Big Bang ↔ Little Bangs • The content of the Universe Dark energy Dark matter Origin of matter • Particle experiments Higgs boson Supersymmetry Matter-antimattter Learn particle physics from the Universe Use particle physics to understand the Universe How Soon Might the NUHM1 be Detected?

O.Buchmueller, JE et al: arXiv:0808.4128 NUHM1 with 1/fb of LHC Data

O.Buchmueller et al