Supersymmetry and Dark Matter

Transcription

1 Supersymmetry and Dark Matter 1/ 52 Supersymmetry and Dark Matter A. B. Lahanas University of Athens Nuclear and Particle Physics Section Athens - Greece

2 Supersymmetry and Dark Matter 2/ 52 Outline 1 Introduction 2 Particle DM Neutrinos and Axions Beyond the SM Detection of DM 3 SUSY Dark Matter Why Supersymmetry? Supersymmetric Dark Matter Candidates 4 Summary

3 Supersymmetry and Dark Matter 2/ 52 Outline 1 Introduction 2 Particle DM Neutrinos and Axions Beyond the SM Detection of DM 3 SUSY Dark Matter Why Supersymmetry? Supersymmetric Dark Matter Candidates 4 Summary

4 Supersymmetry and Dark Matter 2/ 52 Outline 1 Introduction 2 Particle DM Neutrinos and Axions Beyond the SM Detection of DM 3 SUSY Dark Matter Why Supersymmetry? Supersymmetric Dark Matter Candidates 4 Summary

5 Supersymmetry and Dark Matter 2/ 52 Outline 1 Introduction 2 Particle DM Neutrinos and Axions Beyond the SM Detection of DM 3 SUSY Dark Matter Why Supersymmetry? Supersymmetric Dark Matter Candidates 4 Summary

6 Supersymmetry and Dark Matter 3/ 52 Introduction Dark Matter and Dark Energy Dark Matter and Dark Energy are the biggest mysteries in modern Cosmology. Evidence for DE is recent ( ) : Universe is being accelerated by vacuum energy - Confirmed from WMAP by accurate measurements of the CMB power spectrum Evidence for DM is old ( ) : Recent WMAP data showed that Universe s matter-energy density is close to its closure density, Universe is flat! Ω total = 1.00 ± 0.01

7 Supersymmetry and Dark Matter 4/ 52 Introduction Dark Matter Evidence for DM Various astrophysical sources have confirmed the existence of Dark Matter (DM) Binding of Galaxies in Clusters ( F. Zwicky, 1933 ) Rotation curves of Galaxies ( V.C. Rubin and W.K. Ford, 1970 ) Bindings of hot gases in clusters Gravitational Lensing observations Large Scale Stucture simulations High z - Supernovae Observations of colliding clusters of Galaxies The most direct and accurate evidence comes from WMAP by measuring anisotropies of the CMB power spectrum 73% DarkEnergy, 23% DarkMatter, 4% Baryons Dark Matter abundance accurately known! Ω DM h 2 0 = σ N. Spergel et al., WMAP collaboration, Astrophys. J. Suppl. 170 (2007) 377

8 Supersymmetry and Dark Matter 5/ 52 Introduction Dark Matter Binding of Galaxies : 1933

9 Supersymmetry and Dark Matter 6/ 52 Introduction Dark Matter Rotations of Galaxies : 1970

10 Supersymmetry and Dark Matter 7/ 52 Introduction Dark Matter

11 Supersymmetry and Dark Matter 8/ 52 Introduction Dark Matter WMAP, CMB anisotropies : 2003

12 Supersymmetry and Dark Matter 9/ 52 Introduction Dark Matter Universe s Energy / Matter

13 Supersymmetry and Dark Matter 10/ 52 Introduction Dark Matter Universe s Energy / Matter

14 Supersymmetry and Dark Matter 11/ 52 Particle DM Neutrinos and Axions Neutrino Dark Matter? In the SM there are six neutrino and antineutrino species ( N ν = 6 ) and if massless ( ) Ω νh0 2 = 7 2 Tν Nν Ω γ 16 T γ Due to their decoupling and their density is ( ) T ν 4 1/3 = T γ 11 Ω ν N ν Ω γ O(10 5 ) Massless neutrinos contribute little to cosmic energy budget! Neutrinos are massive, Super - K ( 1998 ) = m ν 0, After decoupling the ratio of their number density to entropy density remains constant. Today n 0 = 0.21 s 0 h(t D ) The entropy d.o.f. at their decoupling temperature T D 2 MeV is h(t D ) = Ω νh0 2 mν 93 ev

15 Supersymmetry and Dark Matter 12/ 52 Particle DM Neutrinos and Axions Hot or Cold Dark Matter? HDM is almost ruled out ( like SM neutrinos!) If neutrinos account for the observed Dark Matter Ω νh = m ν 10 ev Too small for dwarf halos requiring: m ν > 120 ev. By Pauli Principle cannot cluster in dwarf halos ( Tremaine and Gunn ) 10 ev too large for structure formation which puts upper limits, m ν < 1.0 ev Non - SM like neutrinos are not ruled out! CDM established by various observations Via Lactea II simulations for the study of DM halo in Milky Way J. Diemand et al, arxiv: [astro-ph] Observations of proto-galaxies ( Very Large Telscope )...

16 Supersymmetry and Dark Matter 13/ 52 Particle DM Neutrinos and Axions Axion Dark Matter QCD instanton effects induce L = αs 4π θ QCD G G Violates C, CP = Electric Dipole Moment of electron d e θ QCD e cm Experimental bounds on d e restricts θ QCD < Why so tiny? Strong CP-problem If massless quark q, by chiral rotation q e iaγ 5 q θ QCD θ QCD 2a due to triangle anomaly! The phase θ QCD is rotated away But quarks are not massless! The effective angle turns out to be Peccei - Quinn (PQ) θ eff = θ QCD argdet(m q) SM includes an additional scalar field Φ, coupled to quarks, and the theory is symmetric under a global axial PQ symmetry

17 Supersymmetry and Dark Matter 14/ 52 Particle DM Neutrinos and Axions Φ e iω Φ Axial symmetry is broken spontaneously at a scale f a, by a scalar potential, i.e. V (Φ) = λ ( Φ 2 f a 2 )2, and a Nambu-Goldstone boson arises ψ f a arg(φ) PQ is broken by quark masses and QCD effects and axion gets a mass pseudo Goldstone boson! PQ current is not conserved : Under a proper PQ chiral rotation µj µ PQ = 2i q Mqγ 5q + αs 2π G G L = αs 4π (θ eff ψ ) G G f a The axion-gluon-gluon terms, ψg G, induce a non-flat potential along the ψ direction and the coefficient of G G relaxes to zero! θ eff ψ = 0 f a

18 Supersymmetry and Dark Matter 15/ 52 Particle DM Neutrinos and Axions The strong CP-problem is resolved! The axion field, the excitation a = ψ ψ, has a mass z f π m π 6.0 ev m a = = 1 + z f a f a 10 6 GeV with z = m u/m d = ± Coupling to two photons : α em α em g aγγ a F F = g aγγ a E 4πf a B πf a g aγγ = 0.36 Dine-Fischler-Srednici, Zhitnitsky model (DFSZ) = 0.97 Kim, Shifman-Vainshtein-Zakharov model (KSVZ) Axions may be observed through their couplings to photons!

19 Supersymmetry and Dark Matter 16/ 52 Particle DM Neutrinos and Axions Large m a ev = 1/f a strong enough and axions can be produced thermally, being decoupled at a temperature T a O(10) MeV, Hot Dark Matter ( like neutrinos) Small m a µev = 1/f a small, axions are not produced thermally but only by vacuum realignement, and their momentum is p a(t 0 ) ev!, Cold Dark Matter CDM density of axions ( ) 7/6 ( ) ev Ω a = 0.5 m a h 0 Axions do not overclose the Universe: Ω a < 1 m a 10 6 ev Limits from stellar cooling: Stars too short a life by copious axion radiation unless m a 10 2 ev Favourite axion mass range: 10 6 ev m a 10 2 ev equivalent to 10 9 GeV f a GeV

20 Supersymmetry and Dark Matter 17/ 52 Particle DM Neutrinos and Axions Axion searches Couplings of axion to photons, matter 1/f a, are suppresed. Axions are hard to detect! Their detection is possible through Primakoff s conversion

21 Supersymmetry and Dark Matter 18/ 52 Particle DM Neutrinos and Axions ADMX is searching for cosmological axions CAST is searching for solar axions Telescopes search for cosmic axions that decay to two gammas Γ(a 2γ) = g aγγ 2 ( ma ev ) 2 sec 1 No axions have been detected but limits on their couplings to photons and masses have been derived not excluding theoretical predictions! If they exist they are good candidates to constitute part, or all, of Universe s CDM

22 Supersymmetry and Dark Matter 19/ 52 Particle DM Neutrinos and Axions

23 Supersymmetry and Dark Matter 20/ 52 Particle DM Neutrinos and Axions

24 Supersymmetry and Dark Matter 21/ 52 Particle DM Beyond the SM Candidates for Dark Matter Thermal, or non-thermal, relics created in the early Universe may constitute part or all of the observed DM WIMPs Weakly Interacting Massive Particles with masses in the EW range O( 100 ) GeV naturally yield Ω DM h , (WIMP miracle) LSP - neutralinos in SUSY theories Heavy ν - like particles KK excitations in ED theories Lightest T-odd particles in little Higgs models Other exotic

25 Supersymmetry and Dark Matter 22/ 52 Particle DM Beyond the SM superwimps Interact with smaller strength ( gravitationally,... ) than WIMPs Gravitino ( superpartner of graviton ) KK gravitons Axino ( superpartner of axion )... Other Candidates Wimpzillas, Cryptons Q - balls BH remnants and other very massive astrophysical objects Moduli fields of String Theory... SUPERSYMMETRY, with conserved R - parity, offers an ideal WIMP candidate! The LSP neutralino ( if the lightest sparticle ). Also gravitino, axino or superpartner of a sterile neutrino.

26 Supersymmetry and Dark Matter Particle DM Detection of DM The interaction strength and masses of DM particles ( http : // /hep/hepap reports.shtm.) 23/ 52

27 Supersymmetry and Dark Matter 24/ 52 Particle DM Detection of DM Supersymmetric DM in colliders The LSP neutralino, if exists, is a leading CDM candidate and may be detected in collider searches. Heavier than the LSP states decay via multi-step-cascade processes to LSP. q, g are among the heavy states, strongly interacting, and if not extremely heavy will have large production X-sections with q q, g g, q g in the final state.

28 Supersymmetry and Dark Matter 25/ 52 Particle DM Detection of DM Direct Detection of DM Neutralino DM is detectable from its elastic scattering with Nuclei ( K. Ni, Erice 2008 ) CDMS, CDMS II 2008 Ge, XENON,... have put limits on the spin-independent elastic cross-section. DAMA / Libra ( Yearly modulation ) Detected signal consistent with DM in the galactic halo! Not confirmed by other experiments, but their results cannot be directly compared in a model independent way.

29 Supersymmetry and Dark Matter 25/ 52 Particle DM Detection of DM Direct Detection of DM Neutralino DM is detectable from its elastic scattering with Nuclei ( K. Ni, Erice 2008 ) CDMS, CDMS II 2008 Ge, XENON,... have put limits on the spin-independent elastic cross-section. DAMA / Libra ( Yearly modulation ) Detected signal consistent with DM in the galactic halo! Not confirmed by other experiments, but their results cannot be directly compared in a model independent way.

30 Supersymmetry and Dark Matter 26/ 52 Particle DM Detection of DM Current and future DD limits

31 Supersymmetry and Dark Matter 27/ 52 Particle DM Detection of DM Indirect Detection of DM WIMP-WIMP annihilation in the galactic halos may be detected through production of γ, neutrinos, anti-matter

32 Supersymmetry and Dark Matter Particle DM Detection of DM Indirect Detection of DM WIMP-WIMP annihilation in the galactic halos may be detected through production of γ, neutrinos, anti-matter 27/ 52

33 Supersymmetry and Dark Matter 28/ 52 Particle DM Detection of DM WIMP-WIMP annihilation in the galactic halos may be detected through production of γ, neutrinos, anti-matter. Production of jets in WIMP + WIMP q q, and eventually γ-rays, may be observed by HESS, Fermi/GLAST ( launched on 11 June 2008 ). Neutrino telescopes, ANTARES, IceCube/AMANDA, SuperK, Nestor, KM3Net, will search for high energy neutrinos. PAMELA ( Payload for Antimatter Matter Exploration of Light nuclei Astrophysics ) is searching for e +, p, by measuring the cosmic flux of anti-particles. PAMELA results : e + in the GeV range show a large excess over the background. Could be signal of DM annihilation in our Galaxy

34 Supersymmetry and Dark Matter 28/ 52 Particle DM Detection of DM WIMP-WIMP annihilation in the galactic halos may be detected through production of γ, neutrinos, anti-matter. Production of jets in WIMP + WIMP q q, and eventually γ-rays, may be observed by HESS, Fermi/GLAST ( launched on 11 June 2008 ). Neutrino telescopes, ANTARES, IceCube/AMANDA, SuperK, Nestor, KM3Net, will search for high energy neutrinos. PAMELA ( Payload for Antimatter Matter Exploration of Light nuclei Astrophysics ) is searching for e +, p, by measuring the cosmic flux of anti-particles. PAMELA results : e + in the GeV range show a large excess over the background. Could be signal of DM annihilation in our Galaxy

35 Supersymmetry and Dark Matter 28/ 52 Particle DM Detection of DM WIMP-WIMP annihilation in the galactic halos may be detected through production of γ, neutrinos, anti-matter. Production of jets in WIMP + WIMP q q, and eventually γ-rays, may be observed by HESS, Fermi/GLAST ( launched on 11 June 2008 ). Neutrino telescopes, ANTARES, IceCube/AMANDA, SuperK, Nestor, KM3Net, will search for high energy neutrinos. PAMELA ( Payload for Antimatter Matter Exploration of Light nuclei Astrophysics ) is searching for e +, p, by measuring the cosmic flux of anti-particles. PAMELA results : e + in the GeV range show a large excess over the background. Could be signal of DM annihilation in our Galaxy

36 Supersymmetry and Dark Matter 29/ 52 Particle DM Detection of DM Fraction of e + measured by PAMELA compared with other experimental data (left). Comparison with theoretical model for secondary production of e + during the propagation of cosmic - rays in our Galaxy (right). O. Andriani et al arxiv: [astro-ph].

37 Supersymmetry and Dark Matter 30/ 52 SUSY Dark Matter Why Supersymmetry? SUSY is a symmetry between fermions and bosons and a natural extension of relativistic symmetries! Resolves the gauge hierarchy problem Induces radiative Electroweak Symmetry Breaking Unifies gauge couplings at large scales GeV Consistent with precision experiments Indispensable ingredient of Superstring Theories Every known particle has a partner ( sparticle ) with spin differing by 2 1 and same mass. SUSY is broken and mass degeneracy is lifted! m sp 2 = m p 2 + M SUSY 2 Theory dictates M SUSY < O(TeV ) and sparticles will (?) be discovered at LHC

38 Supersymmetry and Dark Matter 30/ 52 SUSY Dark Matter Why Supersymmetry? SUSY is a symmetry between fermions and bosons and a natural extension of relativistic symmetries! Resolves the gauge hierarchy problem Induces radiative Electroweak Symmetry Breaking Unifies gauge couplings at large scales GeV Consistent with precision experiments Indispensable ingredient of Superstring Theories Every known particle has a partner ( sparticle ) with spin differing by 2 1 and same mass. SUSY is broken and mass degeneracy is lifted! m sp 2 = m p 2 + M SUSY 2 Theory dictates M SUSY < O(TeV ) and sparticles will (?) be discovered at LHC

39 Supersymmetry and Dark Matter 31/ 52 SUSY Dark Matter Why Supersymmetry?

40 Supersymmetry and Dark Matter 32/ 52 SUSY Dark Matter Why Supersymmetry? The minimal SUSY model The lightest neutralino mass eigenstate, combination of qualifies as a WIMP! H, Z, W

41 Supersymmetry and Dark Matter 33/ 52 SUSY Dark Matter Why Supersymmetry? SUSY unifies gauge couplings!

42 Supersymmetry and Dark Matter 34/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Three leading candidates in Supersymmetry! Neutralino LSP, χ χ χ It qualifies as a WIMP. It is neutral, uncolored, interacting weakly. In SUSY models with R-parity conservation it is stable, if the Lightest Supersymmetric Particle. The best motivated SUSY DM candidate, likely to be seen in LHC. ψ µ Gravitino, ψ µ A spin-3/2 Rarita-Schwinger field, partner of the graviton, emerging in the gauged Supersymmetry ( Supergravity ). It is the gauge field of the local supersymmetric transformations, which are broken at an uknown scale M s, resulting to a gravitino mass m 3/2 M2 s M Planck It interacts only gravitationally and if the lightest may a DM candidate. Axino, ããã Superpartner of the axion, interacting feebly with the rest of the particles like its axion partner.

43 Supersymmetry and Dark Matter 34/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Three leading candidates in Supersymmetry! Neutralino LSP, χ χ χ It qualifies as a WIMP. It is neutral, uncolored, interacting weakly. In SUSY models with R-parity conservation it is stable, if the Lightest Supersymmetric Particle. The best motivated SUSY DM candidate, likely to be seen in LHC. ψ µ Gravitino, ψ µ A spin-3/2 Rarita-Schwinger field, partner of the graviton, emerging in the gauged Supersymmetry ( Supergravity ). It is the gauge field of the local supersymmetric transformations, which are broken at an uknown scale M s, resulting to a gravitino mass m 3/2 M2 s M Planck It interacts only gravitationally and if the lightest may a DM candidate. Axino, ããã Superpartner of the axion, interacting feebly with the rest of the particles like its axion partner.

44 Supersymmetry and Dark Matter 34/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Three leading candidates in Supersymmetry! Neutralino LSP, χ χ χ It qualifies as a WIMP. It is neutral, uncolored, interacting weakly. In SUSY models with R-parity conservation it is stable, if the Lightest Supersymmetric Particle. The best motivated SUSY DM candidate, likely to be seen in LHC. ψ µ Gravitino, ψ µ A spin-3/2 Rarita-Schwinger field, partner of the graviton, emerging in the gauged Supersymmetry ( Supergravity ). It is the gauge field of the local supersymmetric transformations, which are broken at an uknown scale M s, resulting to a gravitino mass m 3/2 M2 s M Planck It interacts only gravitationally and if the lightest may a DM candidate. Axino, ããã Superpartner of the axion, interacting feebly with the rest of the particles like its axion partner.

45 Supersymmetry and Dark Matter 34/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Three leading candidates in Supersymmetry! Neutralino LSP, χ χ χ It qualifies as a WIMP. It is neutral, uncolored, interacting weakly. In SUSY models with R-parity conservation it is stable, if the Lightest Supersymmetric Particle. The best motivated SUSY DM candidate, likely to be seen in LHC. ψ µ Gravitino, ψ µ A spin-3/2 Rarita-Schwinger field, partner of the graviton, emerging in the gauged Supersymmetry ( Supergravity ). It is the gauge field of the local supersymmetric transformations, which are broken at an uknown scale M s, resulting to a gravitino mass m 3/2 M2 s M Planck It interacts only gravitationally and if the lightest may a DM candidate. Axino, ããã Superpartner of the axion, interacting feebly with the rest of the particles like its axion partner.

46 Supersymmetry and Dark Matter 35/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Neutralino DM Neutralinos are Majorana spin-1/2 fermions. They can annihilate in pairs to SM particles. They are produced by the inverse process if A, B have sufficient energies ( High temperatures T >> m χ ) Their annihilation cross section σ A controls the change of their number density through Boltzmann equation dn = 3 H n v σ A ( n 2 neq 2 ) dt H Hubble expansion rate, n eq = equilibrium number density, v = Möller velocity

47 Supersymmetry and Dark Matter 36/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates 3 H n dilution due to Hubble expansion. vσ A n 2 depletion due to χ χ AB. + vσ A neq 2 resupply due to AB χ χ Y = n/s : Number density to entropy density dy dt = 2π2 45 T 2 h H 1 < vσ A > (Y 2 Yeq 2 ) Entropy conservation is assumed after freeze-out, sa 3 = constant s = 2π2 45 h(t )T 3, h(t ) = entropy d.o.f What if we have late entropy production? Hubble expansion rate radiation dominated at freeze-out ( ) 1/2 8πGN H = ρ r, ρ r = π g eff (T ) T 4 What if Universe not radiation dominated at freeze-out?

48 Supersymmetry and Dark Matter 37/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Calculate thermal average vσ A

49 Supersymmetry and Dark Matter 38/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Solve to obtain Y today and then n today and the matter density today ρ χ = n today m χ Standard scenario: Radiation dominated Universe at decoupling and no late entropy production = Neutralino Matter Density : ϱ χ = ( 4π3 1/2 45 ) T 3 χ M Planck geff (T F ) J J xf 0 Neutralino temperature : vσ dx, x F = T F /m χ T 3 χ = 4 11 g eff (1 MeV ) 3 T γ g eff (T F ) Relic Density : Ω χ h 2 0 = GeV 1 M Planck geff (T F ) J

50 Supersymmetry and Dark Matter 39/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates 1 For high temperatures χ χ χ are in thermal equilibrium χ χ AB with the rest and their density is diluted because of expansion. 2 As temperature drops χ χ AB and their number is reduced. Eventually at the freeze-out temperature, T F, vσ A n = H. 3 For T < T F density too low for annihilation to track the expansion, vσ A n << H and their total number is locked!

51 Supersymmetry and Dark Matter 40/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Co-annihilations If next to LSP neutralino, say τ τ τ, has small mass difference M, coannihilations should be included! The key parameter is M = m τ m χ Since T F 0.1 m χ coannihilations negligible for M O(1) m χ but important for small M O(0.1) m χ!

52 Supersymmetry and Dark Matter 41/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Supersymmetry is parametrized by uknown parameters m 0, m 1/2 which set M SUSY and determine sparticle mass spectrum and relic densities ( Public codes available to calculate accurately neutralino relic density, MicroOmegas, DarkSUSY,... ) WMAP data restricts the parametric space and the potential of discovering supersymmetry at LHC

53 Supersymmetry and Dark Matter 42/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Gravitino The spin-3/2 gravitino G G G field is the gauge fermion of local SUSY transformations an partner of graviton. It acquires a mass m 3/2 after SSB of local SUSY ( superhiggs effect ) m 3/2 M2 S M Planck It couples gravitationally to matter with couplings 1 M Planck A µ, λ gauge-boson and its partner ( gaugino ) f L, f L fermion and its partner ( sfermion )

54 Supersymmetry and Dark Matter 43/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates G G G s are produced by inelastic scattering processes during the reheating of the Universe after inflation ( Bolz, Brandenburg and Buchmuller 2001, Pradler and Steffen 2006 ) Solve Boltzmann n G dt + 3Hn G = C G, C G = collision terms to obtain the gravitino yield for T T R, ( Y G n G n γ ) 1 + m2 g 3 m 3/2 2 T GeV 10 10

55 Supersymmetry and Dark Matter 44/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Unstable Gravitino Decays to radiation G γ + γ ( ) 3 τ GeV m 3/2 Decays to hadrons G g + g, q + q ( ) 3 τ GeV m 3/2 For m 3/2 = 10 2 GeV 10 TeV gravitino decays during and after primordial Nucleosynthesis with disastrous effects for BBN! Their overproduction dissociates light nuclei γ + 3 He D + p, γ + D n + p Gravitino Problem!

56 Supersymmetry and Dark Matter 44/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Unstable Gravitino Decays to radiation G γ + γ ( ) 3 τ GeV m 3/2 Decays to hadrons G g + g, q + q ( ) 3 τ GeV m 3/2 For m 3/2 = 10 2 GeV 10 TeV gravitino decays during and after primordial Nucleosynthesis with disastrous effects for BBN! Their overproduction dissociates light nuclei γ + 3 He D + p, γ + D n + p Gravitino Problem!

57 Supersymmetry and Dark Matter 44/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Unstable Gravitino Decays to radiation G γ + γ ( ) 3 τ GeV m 3/2 Decays to hadrons G g + g, q + q ( ) 3 τ GeV m 3/2 For m 3/2 = 10 2 GeV 10 TeV gravitino decays during and after primordial Nucleosynthesis with disastrous effects for BBN! Their overproduction dissociates light nuclei γ + 3 He D + p, γ + D n + p Gravitino Problem!

58 Supersymmetry and Dark Matter 45/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates For late decaying particles X bounds on their lifetimes τ X and abundances Y X are imposed by BBN. For gravitino these translate to bounds on T R and its mass m 3/2! T R = GeV for m 3/2 = 10 2 GeV 3 TeV In contradiction with thermal Leptogenesis scenarios which require T R 10 9 GeV and Inflation models with T R > 10 7 GeV! Kawasaki M, Kohri K and Moroi T, 2005

59 Supersymmetry and Dark Matter 46/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Gravitino DM If the gravitino is the LSP the gravitino problem may be avoided but the next to LSP particles (NLSP), neutralino χ χ χ or stau τ τ τ, decay late! χ χ χ as NLSP is disfavoured by BBN bounds BBN bounds are weaker for the τ τ τ! Catalyzed BBN, Pospelov M, 2006 Bound-state formation of long-lived negatively charged particles with the primordial nuclei enhances 6 Li production by almost seven orders of magnitude putting severe upper limits on τ τ τ abundances, prior to their decays!

60 Supersymmetry and Dark Matter 46/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Gravitino DM If the gravitino is the LSP the gravitino problem may be avoided but the next to LSP particles (NLSP), neutralino χ χ χ or stau τ τ τ, decay late! χ χ χ as NLSP is disfavoured by BBN bounds BBN bounds are weaker for the τ τ τ! Catalyzed BBN, Pospelov M, 2006 Bound-state formation of long-lived negatively charged particles with the primordial nuclei enhances 6 Li production by almost seven orders of magnitude putting severe upper limits on τ τ τ abundances, prior to their decays!

61 Supersymmetry and Dark Matter 46/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Gravitino DM If the gravitino is the LSP the gravitino problem may be avoided but the next to LSP particles (NLSP), neutralino χ χ χ or stau τ τ τ, decay late! χ χ χ as NLSP is disfavoured by BBN bounds BBN bounds are weaker for the τ τ τ! Catalyzed BBN, Pospelov M, 2006 Bound-state formation of long-lived negatively charged particles with the primordial nuclei enhances 6 Li production by almost seven orders of magnitude putting severe upper limits on τ τ τ abundances, prior to their decays!

62 Supersymmetry and Dark Matter 47/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates The decays of the NLSP particles χ Gγ, τ Gτ produce gravitinos non-thermally. Their total density = Ω G = Ω G (thermal) + m 3/2 Ω NLSP m NLSP

63 Supersymmetry and Dark Matter 47/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates The decays of the NLSP particles χ Gγ, τ Gτ produce gravitinos non-thermally. Their total density = Ω G = Ω G (thermal) + m 3/2 Ω NLSP m NLSP

64 Supersymmetry and Dark Matter 47/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates The decays of the NLSP particles χ Gγ, τ Gτ produce gravitinos non-thermally. Their total density = Ω G = Ω G (thermal) + m 3/2 m NLSP Ω NLSP Gravitino Dark Matter, with stau NLSP, inconsistent with T R > 10 7 GeV in the popular supersymmetric models.

65 Supersymmetry and Dark Matter 48/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Gravitino Dark Matter, with stau NLSP, incosistent with T R > 10 7 GeV in the popular supersymmetric models. Ways to avoid it : Depart from the simple supersymmetric schemes SUSY violates R-parity τ τ τ decays to SM particles before Nucleosynthesis as its lifetime shortens. Late entropy production mechanisms Gravitino abundances are diluted. Stau abundance Y τ, before its decay, is depleted Can occur by enhancing stau-higgs coupling or staus annihilate fast via Higgs resonance....

66 Supersymmetry and Dark Matter 49/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Axino DM Axinos, ããã, have masses in the kev GeV range and their couplings are suppressed by the PQ breaking scale f a. Interact more weakly than a WIMP but not as weakly as a gravitino! Thermal production: Not in thermal equilibrium, are produced thermally via scattering, like gravitinos! Covi L, Kim J E, Roszkowski L & Kim H B, Brandenburg A & Steffen F, 2004 ( ) ( Ω (th) ã h g 6 11 ) 2 GeV ( ) ( ) mã T R s ln g s f a 100 MeV 10 4 GeV The lifetime for decays χ γã are 0.01 sec, before BBN! The axino less constrained than gravitino! The NLSP decays, χ γã, produce axinos non-thermally Ωã h0 2 = Ω(th) ã h0 2 + m ã Ω NLSP h0 2 m NLSP

67 Supersymmetry and Dark Matter 49/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Axino DM Axinos, ããã, have masses in the kev GeV range and their couplings are suppressed by the PQ breaking scale f a. Interact more weakly than a WIMP but not as weakly as a gravitino! Thermal production: Not in thermal equilibrium, are produced thermally via scattering, like gravitinos! Covi L, Kim J E, Roszkowski L & Kim H B, Brandenburg A & Steffen F, 2004 ( ) ( Ω (th) ã h g 6 11 ) 2 GeV ( ) ( ) mã T R s ln g s f a 100 MeV 10 4 GeV The lifetime for decays χ γã are 0.01 sec, before BBN! The axino less constrained than gravitino! The NLSP decays, χ γã, produce axinos non-thermally Ωã h0 2 = Ω(th) ã h0 2 + m ã Ω NLSP h0 2 m NLSP

68 Supersymmetry and Dark Matter 50/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates Falls within the WMAP range, for temperatures T R 10 8 GeV

69 Supersymmetry and Dark Matter 51/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates SUSY seems the right theoretical framework to unify, predicting new particles that may constitute part, or all, of the observed DM. Physics of inflation and mechanisms of Universe s reheating are essential in order to understand and quantify better the production of Dark Matter abundances.

70 Supersymmetry and Dark Matter 51/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates SUSY seems the right theoretical framework to unify, predicting new particles that may constitute part, or all, of the observed DM. Physics of inflation and mechanisms of Universe s reheating are essential in order to understand and quantify better the production of Dark Matter abundances.

71 Supersymmetry and Dark Matter 51/ 52 SUSY Dark Matter Supersymmetric Dark Matter Candidates SUSY seems the right theoretical framework to unify, predicting new particles that may constitute part, or all, of the observed DM. Physics of inflation and mechanisms of Universe s reheating are essential in order to understand and quantify better the production of Dark Matter abundances.

72 Supersymmetry and Dark Matter 52/ 52 Summary Summary Particle physics offers compelling candidates to resolve the Dark Matter mystery. The elusive Axion is a viable candidate. On-going and future experiments may confirm its existence. Extensions of the Standard Model, and in particular SUSY, predict well-motivated candidates. Good opportunity to discover DM in accelerators (LHC...), as well as in direct and indirect detection experiments. Astrophysical and accelerator searches unite to test particle physics theories and probe the Universe before the era of Nucleosynthesis. We are entering into a very exciting era in Astroparticle Physics!

73 Supersymmetry and Dark Matter 52/ 52 Summary Summary Particle physics offers compelling candidates to resolve the Dark Matter mystery. The elusive Axion is a viable candidate. On-going and future experiments may confirm its existence. Extensions of the Standard Model, and in particular SUSY, predict well-motivated candidates. Good opportunity to discover DM in accelerators (LHC...), as well as in direct and indirect detection experiments. Astrophysical and accelerator searches unite to test particle physics theories and probe the Universe before the era of Nucleosynthesis. We are entering into a very exciting era in Astroparticle Physics!