To start… [email protected] Luigi Cappiello & Gianpiero Mangano 20 novembre 2008 Direct measurements (nuclear recoils) LEP, Tevatron, precision meaurements Cosmology, Relic abundance DM Candidate LHC Antimatter fluxes Gamma experiments v fluxes The Candidate: Kaluza Klein Dark Matter Theories with compactified extra dimensions allows for infinite towers of heavy states corresponding to all SM degrees of freedom (Universal Extra Dimensions UED) KK DM Boson, s-wave annihilation SUSY DM (e.g. Neutralino) Majorana fermion, p-wave annihilation X 3 + 1 spacetime dimensions R D extra dimensions compactified as circles, torii etc. Problems: extra massless states, chiral structure of the Standard Model Solution: Orbifolding, KK parity Standard Model Lagrangian Plane wave decomposition Consider photon field (4+1 dimensions): A massless A5 ?? Fermion fields interact chirally, e.g. lepton SU(2) doublet LL In 5 dimensions no chirality. Orbifolding: R S S/Z2 0 Fields can be assigned a parity under orbifold transformation (odd, even) Boson fields Fermion (chiral) fields KK excitations of (chiral) fermions are vector-like under SM group KK parity is conserved in interactions (unless explicitly broken) In 5 dimensions: KKP = (-1)n i) KK odd excitations only produced in pairs ii) Lighest KK (n=1) state is stable. Candidate for DM Particle Spectrum Tree level: E2 = p2 + m2 + n2/R2 Radiative corrections due to breaking of 5-d Lorentz invariance Best DM candidate: photon – like KK UED pro’s and con’s con’s 1. it does not solve the hierarchy problem 2. do not include gravity 3. Stabilization of extra dimensions ? pro’s 1. UED DM candidate is a necessary outcome of the model 2. DM constraint and indirect limits on compactification radius guarantee a spectrum which is within the reach of LHC 3. First excited states of the SM particles should be between 400 – 900 GeV Cosmology: the relic abundance Relic particles should be uncharged under SU(3)c or U(1)Q (non anomalous heavy matter-KK isotopes from observations KK excitations of Z and neutral Higgs typically heavier KK neutrinos have too large scattering cross sections on nuclei (CDMS) B (photon) natural KKDM candidate Relic density fixed by annihilation cross section g 2 3 mB 1 4 y S-wave! Relic abundance, scattering off nuclei (direct searches) and annihilation in the local halo (indirect searches) intertwined Bino: p-wave into ~ B fermions f ~ B ~ f f Computing the relic abundance 1/ 2 3 x T 4 Gg ( m ) xfr 2 fr 0 h 0.3 45 30 v cr 10 xfr : n eq ( xfr ) v H ( xfr ) 3 gy4 3 mB21 1/2 g ( m ) 100 10 39 cm2 v Direct measurements (nuclear recoils) DM-nucleus elastic scattering Many running and planned experiments: CDMS, Edelweiss, Zeplin, CRESST, CLEAN, COUPP, DEAP, DRIFT, EURECA, SIGN, XENON, WARP, KIAS, NaIAD, Picasso, Majorana, DUSEL, IGEX, ROSEBUD, ANAIS, KIMS, Genius, DAMA, LIBRA Spin independent: + quark – KK quark loops Spin dependent large but under future experiment sensitivity Gamma experiments Gammas (and energetic neutrinos and antimatter) can be produced from LKP by annihilations in high density structures (center of galaxy, clumps,…) Productions of continuum via final state radiation and line emissions via loop processes DM in halos typically mass independent and universal (N-body simulation), as e.g. NFW, but results do not include baryonic matter Background: astrophysical sources emit up to (and above) 10 TeV HESS, MAGIC Main channels are lepton and quark pairs which decay and fragment (neutralino is quite different…) Smoking guns: gamma lines from , Z, H processes Perspectives: GLAST covers sub-GeV up to 300 GeV region For a NFW up to 3-4 events per year above few GeV expected from the galactic center, but galactic background is high Mini halo, clump rate difficult to assess v fluxes v fluxes produced in the halo difficult to observe. Larger effect if KKDM gets captured in the sun and then annihilates Capture rate and annihilation rate leads to stationary conditions for Neutrinos produced directly via charged leptons (tau) and pions Energetic neutrinos produced more than in neutralino scenario IceCube or Km3Net Present bounds from SK, Amanda, Baksan =(mq1-mB1)/mB1 3 -sigma detection (atmospheric neutrino background) LEP, Tevatron, precision meaurements LEP EW Precision Observables 1-UED new physics contribution to gauge boson vacuum polarization 95 Summary of constraints From rare decays and flavor physics 95%CL 99 99%CL 1) 2) Lower and upper bonds on R-1 SM 1) Loop effects K-top, KK-W, K-scalar 2) Loop effects K-top, KK-H UED Interesting effects also on rare decays, e.g. Accelerator Searches: Tevatron Mass spectrum of n=1 level (after rad. Corr.) Decays ( KK-parity conserved ) Process CDF L=87.5 pb -1 (KKqq) =3,3pb(2.5pb) 95%CL(90%CL) 1/R>270 (280) GeV (KKqq, KK-qg, KK-gg ) =7,9pb(6.0pb) 95%CL(90%CL) 1/R>280 GeV Future Colliders and UED LHC: Discovery machine but Problems with signature Production cross-section of KK-pairs Largest overall rate through q1 pairs (small) Emiss + (N 2) Jets (soft) 1/R < 1.2 TeV Gold plate channel Tot. Integr. Luminosity vs 1/R Emiss + 4 leptons UED discovery reach in the golden plate channel. 5-s excess of 5 signal events L vs 1/R Other channels affected by larger backgrounds Warning: estimates are somewhat model-dependent on assumpption on the relevance of counterterms in the UED lagrangian coming from the boundary points (0, pR) Could change the mass spectrum ILC: Accurate measurements of UED particle properties and discrimination of UED from other scenarios i.e. SUSY N=1 pair production Resonant production of B2 and Z2 for s1/2=1TeV and 250GeV<R-1<450 GeV Cross-section and forward-backward Asymmetry vs 1/R for N=2 single KK mode production N=1 KK Resonant production of B2 and Z2 N=2 KK N=1 KK 95% CL exclusion limits from combined leptonic and hadronic final states at ILC Antimatter searches ( before PAMELA data ) Generically, WIMP annihilations (*) yeld as much matter and antimatter in cosmic rays KK anomaly KK (*) in the Galactic halo e- e+ excess of e+/(e++e-) at high EKin >7-10GeV anti-deuteron anti-proton positron Flux Vs Kin.Energy The longer the path toward the observed e+ spectrum ... Galaxy hard e+ KK soft e+ Diffusion KK (Inv. Compton, sync. rad. ] S-wave enhancement due to Sommerfeld effect (DM clumps ? Spatial inhomogeneities) Solar modulation ... the harder is the work to calculate it. Use PYTHIA Halo model of DM distribution (r) Diffusion model modeled on Cosmic Rays Use e+/(e++e-) Boost factors or Sommerfeld effect To be continued ... PAMELA et al.