Probing Supersymmetric Baryogenesis: from Electric Dipole Moments to Neutrino Telescopes

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1 Stefano Profumo California Institute of Technology TAPIR Theoretical AstroPhysics Including Relativity Kellogg Rad Lab Probing Supersymmetric Baryogenesis: from Electric Dipole Moments to Neutrino Telescopes Based on: V.Cirigliano, S.Profumo and M.Ramsey-Musolf Musolf, JHEP07(2006)002 Ohio State University Columbus, Friday, September 8, 2006

2 The Nightmare of Popper s s Quote In so far as a scientific statement speaks about reality, it must be falsifiable: And in so far as it is not falsifiable it does not speak about reality Karl Popper, The Logic of Scientific Discovery Supersymmetric Electro-Weak Baryogenesis: a falsifiable theory

3 Baryon Asymmetry of the Universe (BAU) Primordial Asymmetry Planck-scale baryogenesis GUT baryogenesis Leptogenesis Affleck-Dine mechanism Electro-weak baryogenesis Y B = n B s γ = (7.3 (8.5 ± ± 2.5) ) BBN WMAP-3y

4 Ingredients of Baryogenesis Baryon Number violation If B is conserved, the present BAU can only reflect asymmetric initial conditions C and CP violation In the absence of a preference for matter or antimatter, B-noncoserving interactions will produce baryon and antibaryon excesses at the same rate: no net baryogenesis Out of Equilibrium conditions In chemical equilibrium the entropy is maximal when the chemical potential associated with all nonconserved quantum numbers vanish (*) A.D.Sakharov, JETP Letters 5, 24 (1967) Sakharov conditions (*)

5 Electro-weak baryogenesis (1/2) The Electro-Weak Phase Transition can, potentially, fulfill all 3 Sakharov requirements (*) (Electro-weak Baryogenesis) Bubbles of broken phase provide the necessary departure from equilibrium, B violation: if the EW Weak phasesphaleron transition is first Transitions order CP violation: CKM Scattering of Out particles of Eq: on Bubbles the spatially of varying broken Higgs EW phase vevs along the bubble walls generate non-zero left-handed chiral currents n L (B-L) conserving but B- and L- violating Weak Sphalerons Transitions are unsuppressed in the unbroken EW symmetry regions, and exponentially suppressed in regions of broken EWS (*) V.A.Kuzmin, V.A.Rubakov and M.E.Shaposhnikov, Phys.Lett. B197, 49 (1989)

6 Electro-weak baryogenesis (2/2) Chiral charge currents asymmetries diffuse in the symmetric phase in front of the bubbles, and are converted into a net baryon number t B ( ) 2 x D ρ ( x) = Γ F ( x) [ n ( x) Rρ ( x) ] ρ + B ws ws L B Baryon number diff.coeff. Sph. transition profile Sph. transition rate Relaxation coeff. A sufficiently strongly first order phase transition ensures that the baryon number which then diffuses inside the bubble is not washed out v( T c ) / T c 1 depends on the finite temperature effective Higgs potential

7 Electro-weak baryogenesis: Summary Out of equilibrium regions (bubble walls) CP-violating interactions generate n L Unbroken Phase Broken Phase Sphalerons convert n L into net baryon number ρ B in the ubroken phase regions ρ B diffuses in the broken EW phase region, and freezes in ρ B It is not washed out if sphal. transitions are strongly suppressed in the br. phase (i.e. if the PT is strongly first order)

8 SM vs MSSM A first order EW phase transition can be induced by the loop effects in the Higgs potential of light bosonic particles with large couplings to the Higgs fields In the STANDARD MODEL Only such particles are gauge boson, but they re not strongly enough coupled to the Higgs fields (or, the Higgs must be too light) SM CP-violating sources are not large enough In the MSSM Additional bosonic degrees of freedom couple to the Higgs (e.g. a light stop, x6) The theory can feature additional CP-violating sources

9 EWB in the MSSM: Requirements In the MSSM, successful EW baryogenesis requires: at odds with: 1. Light enough stop m < ~ t m t 1 m~ t > 1 (LEP-II) 95GeV 2. Light enough Higgs m h <120GeV m h >114GeV (LEP-II) 3. Strong enough CP-violating sources (3rd generation squarks, higgsinos) e, n and atomic EDM s

10 Interludium: Neutralinos and Charginos M N = M 1 0 Gaugino Mass Relations 0 -m Z cos(mβ 1 sin = αθ W M 2 ) m Z cos β cos θ W M 2 m Z sin β sin θ W -m Z sin β sin θ W -m Z cos β sin θ W m Z cos β cos θ W 0 -μ m Z sin β sin θ W -m Z sin β sin θ W -μ 0 χ= Ν 11 B 0 + Ν 12 W 0 + Ν 13 H d 0 + Ν 14 H u 0 μ μ e i φ μ BINO WINO HIGGSINO M C = M 2 m W μ 2 cos β g v d (x) 2 m 2 sin β W g v u 2 (x)

11 EWB in the MSSM: Setup Free parameters in the game: M,, 1 M 2 μ, φμ The second stop must be heavy, and mostly left-handed Increase the Higgs mass m~ m, m~ = 10 TeV t 1 t t 2 Reduce the SUSY contribution to Δρ Other sfermions must be heavy to suppress CP-violating processes (e.g. 1-loop EDM s) ~ 10 TeV m f The Higgs mass bound also constrains 5 tan β 10 The generated BAU also depends on the heavy MSSM Higgs sector through Δβ m A =150 GeV, 1000 GeV

12 Resonant EW Baryogenesis The strongest possible CP-violating source arises if resonant conditions are met in the gaugino-higgsino sector M 1,2 μ v (x) v(y) x ~ μ ~ W, B ~ x ~ H ( ) M 2, M ) H ( 1 Resonant Chargino Source: Well known fact (*) Resonant Neutralino Source: Novelty! Connection with Dark Matter!! (*) M.Carena et al., Nucl.Phys. B (2003)

13 EW Baryogenesis and DM In the (R-parity conserving) MSSM the LSP is stable The LSP must be a phenomenologically viable relic (electrically and color neutral, low enough relic abundance and direct detection rates) Mass (a): EWB and DM are unrelated (b): EWB-DM connection

14 Purposes of our project 1. What are the MSSM parameter space regions compatible with EWBG? Do they overlap with regions of good neutralino relic abundance? 2. If EWBG is the mechanism of baryon asymmetry generation, will the EDM s be large enough to be detected? 3. If EWBG is related to DM Do we expect sizable DM detection rates? How detection rates change with CP-violation? 4. If EWBG is not related to DM, do we have a ( guaranteed ) chance of observing SUSY at colliders?

15 Baryon Asymmetry in the MSSM What we learn: 1. sub-tev mass parameters Central WMAP BAU 2. sinφ μ >0.01 Neutralino Neutralino driven driven baryogenesis baryogenesis 3. Two-funnel structure Central WMAP BAU Neutralino Neutralino driven driven baryogenesis baryogenesis Supergravity -like gaugino mass pattern 2 5 sin ϑw M 1 = M sin ϑ W 2 / 2 Anomaly mediation -like gaugino mass pattern M g 2 1 M 2 3 g g1 = β β 1 M 2 g 2

16 Electric Dipole Moments CP-violating interactions in the SUSY sector induce EDMs In the present setup, the best probe is the electron EDM 1-loop (electron) EDM Asymptotically vanish in the limit of large sfermion masses 2-loop EDM Only contribution In SplitSUSY In general, d sin( φ ), but with different dependence e, Y B μ upon the SUSY parameter space (m A,μ,M 1,2 )

17 EDMs and EW Baryogenesis sinφ μ 1 Only two-loop EDMs (heavy sfermions limit) Anomaly mediated case even worse! Maximal phases are not compatible with EW Baryogen. exp, cur d e e cm

18 EDMs and EW Baryogenesis sin φ μ <1 What we learn: 1. EDM and EWB are compatible 2. maximal phases are excluded by current data 3. there is a lower bound on the el. EDM 28 d e 10 e cm >> d e exp, fut e cm EDM experiments will conclusively test the EW Baryogenesis scenario!

19 EWB and DM: a closer look M 1,2 The higgsino mixing is required to have a low enough relic abundance in the N χ M 1 h μ case and fulfill EWB + right thermal χ production Large higgsino mixing implies large couplings to the Higgses, and hence large direct detection rates even with heavy s-quarks μ B ~ B ~ H ~ Since ~ the DM particle is light this means that m ~χ < m t < m t 1 1 the local DM number density is large the number of pair annihilations is large ( ρ = m n ) DM DM ( 2 n ) DM DM

20 The Neutralino Relic Abundance & EWB m A =1 TeV, sin(φ μ )=0.5 Resonant s(h) ann. Stop coann. Excessive relic abundance regions are ruled out (caveat: low-t reheating) Bino-Higgsino mixing m ~χ < m~ t < m t 1 1 Low relic abundance regions are viable assuming either non-thermal production or cosmological enhancement η Ω ( WMAP th ) th Ω Ω Ω CDM χ / χ In the anomaly mediated SUSY bckg. case 30 η Ω 300 Neutralinos can be responsible for both Baryogenesis and Dark Matter

21 Direct & Indirect Dark Matter Searches DIRECT DETECTION Observe scattering of χ s off nuclei in low bckg. environments NEUTRINO FLUXES Look for neutrinos produced in χχ ann. in the core of gravitational dips, like the center of the Sun or of the Earth ANTIMATTER SEARCHES GAMMA RAYS Disentangle antimatter Observe gamma produced in χχ ann. ANTIMATTER AND GAMMA rays RAYS produced RATES in the galactic halo from by χχ CRITICALLY DEPEND UPON THE ASSUMED standard antimatter ann. in the sources DARK MATTER HALO galactic MODEL center!!

22 Neutrino Telescopes SuperKamiokande Low energy threshold (1 GeV) SuperK data already constrain some SUSY models IceCube High energy threshold (~50 GeV) 9/80 strings deployed (14/y)

23 Neutrino Telescopes & Dark Matter Capture through scattering in the Sun/Earth Gravitational collapse in the center DM starts to pair-annihilate annihilate producing (also) neutrinos Annihilation-Capture Equilibrium

24 Dark Matter searches and EWB All the CP parameter conserving space case will (no be EWB) within reach of next CP generation violating case direct (EWB) detectors and of km 2 size neutrino telescopes (e..g IceCube) A sizable portion of the parameter space which we expect to be compatible with EWB is already ruled out by SuperK data on the neutrino flux from the Sun CP phases suppress direct detection and enhance the neutrino flux f/sun

25 Dark Matter searches and EWB: Zooming Out Supergravity mediated SUSY breaking Anomaly mediated SUSY breaking Both ton-sized direct detectors AND neutrino telescopes will conclusively probe EW Baryogenesis!

26 Collider Searches m~ t 1 < Tevatron (*) m~ χ + 1 ~ t cχ~ LHC same sign top (**) LHC trilepton (*) Demina et al, PRD (2000); (**) Kraml&Raklev, 2005; (***) Carena et al, 2005 e e + + e e ILC (***) ILC ~ ~ χ + χ 1 1 * ~ t ~ 1 t 1

27 Ongoing Research: Beyond the MSSM (1/2) Adding a Gauge Singlet Superfield S to the Superpotential strongly affects SUSY EWB, adding tree-level trlinear field terms ( *) 1 3 W = μh d Hu + hs H d HuS + ks + αs + u u d d u + 3 ( c c c g Qu H + g Qd H g g Le H ) (as general as possible, including the μ-term, linear and cubic terms in S) (**) The corresponding tree level scalar field potential reads: e d (*) M.Pietroni, Nucl.Phys. B402 (1993) 27; (**) Davies et al., Phys.Lett. B372 (1996) 88

28 Ongoing Research: Beyond the MSSM (2/2) 1. The EWPT is more naturally strongly first order (e.g. if the singlet Higgs is light) 2. The bound on the Higgs mass is alleviated (both for EWB and theoretically) 3. No need for light stops 4. Extra possible non-trivial CP-structure Scopes of the project: Study the dynamics of the EWPT (bubble walls, diffusion, wash-out ) Assess the new contribution to EW precision observables Study the CP-structure Evaluate the new contributions to Electric Dipole Moments DM physics (light singlino )

29 Conclusions Two-funnel structure (chargino & neutralino driven) Will be probed by next generation electron EDM exp MSSM EW Baryogenesis Could be seen at LHC Will be probed at ILC What lies BEYOND? Compatible (and/or( and/or connected) with Neutralino CDM Already constrained by SuperK Will be probed at - IceCube -Ton-Sized Dir.Det.

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31 Neutralino-induced induced Neutrino flux from the Sun Indirect detection techniques which doesn t depend critically upon the dark matter halo profile The capture rate for a given WIMP species in the Sun reads C Sun s -1 ρlocal 0.3 GeV/cm km/s v local 3 σ H,SD + σ H,SI σ pb He,SI 100 GeV m WIMP 2 The annihilation rate of accumulated WIMPs in the Sun is given by A Sun = σ v / Veff where The number N of WIMPs in the Sun follows from V eff = N& 27 = C cm Sun GeV m WIMP A Sun N 2 3/ 2 and gives the rate of WIMP annihilations today, Γ = 1 2 Sun 2 A N = 1 2 C Sun tanh 2 ( ) Sun Sun Sun t C A t Sun y This, together with the model-dependent neutrino yield per WIMP annihilation, gives the flux of neutrinos from the Sun

32 Gamma Rays from DM annihilations: GC φ γ DM (E i ) < φ γ meas (E i ) + 2σ γ (E i ) (95% C.L.) All SUSY models The HESS (and EGRET) data on the GR flux from the Galactic Center constrain many WIMP models!! SUSY models with χ thermal relic abundance WMAP-compatible Critical Dependence on the inner structure of the DM Halo!

33 Gamma Rays from DM annihilations: Draco Best fit halo models; Spread depends on different halo profiles (Burkert, NFW, Diemand05) Extreme halo choices (consistent with general structure formation constraints and dynamical info on Draco) (*) N + sig < 2 Nsig Nbckg N N E γ γ >100 GeV

34 Gamma Rays: constraints from GC and Draco Only with extremely cuspy halo profiles CACTUS constrains standard SUSY-DM models The CACTUS-Draco cnstr. is stronger than the constraints from the GC if a cored MW DM halo is assumed EWB-compatible models are generically not constrained by GR data

35 Conclusions The MSSM parameter space compatible with ElectroWeak Baryogenesis features a two-funnel structure (neutralino- and chargino-driven) The ( new ) neutralino-driven funnel connects EWB and the Dark Matter physics The EWB scenario will be thoroughly tested at future eedm experiments EWB and a good DM relic density are compatible in the MSSM Direct detection is suppressed by CP-violation in the higgsino sector, while neutrino telescopes rates are enhanced Neutrino telescopes are a formidable probe of the EWB parameter space: (1) the neutralino-driven funnel is strongly constrained by SuperK, and (2) IceCube will conclusively test the scenario Gamma-Rays constraints are not effective on the EWB parameter space (CACTUS constraints from Draco might be, however, stronger than from the GC) LHC and the ILC are complementary, all will exhaustively probe the EWB setup