Technicolor Dark Matter. Chris Kouvaris Université Libre de Bruxelles

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1 Technicolor Dark Matter Chris Kouvaris Université Libre de Bruxelles

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3 Dynamical Symmetry breaking: The motivation for Technicolor Long time before QCD BCS showed that the Fermi surfaces are unstable to formation of Cooper pairs, if there is an attractive channel, no matter how weak it appears to be Superfluidity Superconductivity Chiral Symmetry Breaking

4 Superconductivity Attractive interaction between electrons (mediated by phonons) Cooper pairs break electromagnetism U(1) to Photons become massive! Meissner effect

5 The idea of Technicolor (Weinberg, Susskind) The Electroweak symmetry breaks dynamically via Technicolor Strong Interactions at ~ 250 GeV by the formation of the condensate W and Z bosons become massive. Higgs is a Cooper pair

6 If Higgs is composed of two techniquarks Extended Technicolor Contribution to the masses of the Nambu-Goldstone bosons Contribution to the masses of the SM fermions Contribution to the flavor changing neutral currents

7 The Problems of the Old Technicolor Theories We need large and small Only way out is walking coupling! but in order to be close at the conformal window for the fundamental representation The S parameter is too large!

8 Higher Dimensional Technicolor F. Sannino and K. Tuominen, hep-ph/ PRD (RC) D.K.Hong, S.D. Hsu, F. Sannino, PLB597 (2004) 90 [hep-ph/ ] D. Dietrich, F. Sannino and K. Tuominen, hep-ph/ PRD D. Dietrich, F. Sannino and K. Tuominen, hep-ph/

9 Minimal Walking Model Spontaneous Symmetry Breaking SU(4) SO(4) 9 Goldstone Bosons Eaten by W s and Z carrying technibaryon number One extra lepton family to cancel Witten s anomaly Tuominen Sannino Gudnason, CK, Sannino

10 Dark Matter Zwicky 1933: Virial Theorem applied on Coma cluster Zwicky took 5*10 15 cm 2 s -2 as the value for the time and mass averaged squared velocity and 2 million light-years for the radius of the cluster. The total cluster mass is then about 7*10 13 solar masses. Since the cluster contains about 1000 galaxies, this yields an average galactic mass of 7*10 10 solar masses. However, the average galactic luminosity in the Coma cluster is found to be only 8.5*10 7 solar luminosities. Thus, the average mass to light ratio, in solar units, of the galaxies in the Coma cluster is approximately 800. Rubin1975: Rotation Curves of Spiral Galaxies

11 Can the Minimal Walking Technicolor provide dark matter candidates? In other words Provide stable, electrically neutral particles Avoid violation of the Electroweak Precision Measurements Give the right relic density Avoid detection from the current dark matter search experiments like CDMS.

12 1. Nambu-Goldstone bosons of the MWT UU, DD, UD Electric charges y+1, y-1, y For y = 1 DD is electrically neutral! If DD is also the lightest technibaryon It carries technibaryon number It can be stable!!! hep-ph/ CK, Sannino, Gudnason

13 Ingredients Calculation of Dark Matter Density Technibaryon-antitechnibaryon asymmetry (Nussinov 85) Weak equilibration Baryon Number violating processes Electric Neutrality Harvey, Turner (1990) Extra Conditions for technicolor UD (DD) W+ TB-L and TB-L, B-L, B-TB are conserved per family UU (UD) ( u d d ) U D U vacuum 3 L L L L L L L L

14 1.Thermal equilibrium for the SM particles and for the new ones 2. Sphaleron processes: freeze out at a temperature T* = GeV 3. Electric Neutrality 4. For a 2 nd order Phase Transition For a 1 st order Phase Transition

15 TB B 3 2 TB m B m TB p

16 or simple Math!!! TB B n n TB B M M TB p n n TB B ~ e M TB / T * e ~ 5

17 Is it fine tuning of initial conditions? NO!!! TB B c Initial condition TB B TB B B c 1 1 B Sphalerons violate B As long as c is nonzero, thermal equilibrium drives the system to the same ratio regardless the specific value of c. Le Chatelier principle: If a chemical system at equilibrium experiences a change in concentration, then the equilibrium shifts to counteract the imposed change.

18 Detection of the Technibaryon The neutral Goldstone boson is 1 DD ( DLDL DRDR ) 2 It couples to the Z boson with the same strength as a SM neutrino ~ ~ g g' g g' Z DD Z DD L L The cross section for elastic scattering off a nucleus is 4 times larger than that of the spin independent of a SM neutrino Lesson: Cross section too large!

19 How to evade detection? Effective Hypercharge should be zero for y = 0: UD becomes neutral, but extra leptons acquire fractional charge, that poses no problem if L =0. Only dipole moment cross section too low Alternatively: Ultra Minimal Technicolor (Ryttov, Sannino) Two Dirac fermions in the fundamental of the SU(2) and one in the adjoint. No extra leptons, no fractional charge for all the particles and zero overall hypercharge. ITIMP (Frandsen, Sannino)

20 Even Better!!! Decaying Dark Matter can explain Pamela results Nardi, Sannino, Strumia Dimension 5 GUT suppressed operators give decays ~7 sec for a TeV particle. They decay too fast! Dimension 6 GUT suppressed operators give decays for TeV particles M ~ 8 M 4 GUT 5 D 27 ~10 sec Dimension 6 operators are natural objects in Technicolor A Technicolor dark matter particle ~TeV can reproduce PAMELA and ATIC results with decays to muons and taus.

21 2. Majorana Technibaryons For y=1, D is neutral CK Antipin, Heikinheimo, Tuominen Because D transforms under the adjoint representation, are colorless!! Majorana mass see-saw mechanism The same analysis holds also for the heavy neutrino of the theory. For y=1/3, it is neutral.

22 2. Majorana Technibaryons Seesaw The Technibaryon number is broken. There is a R-parity as in neutralinos. We fix the mixing angle by demanding the relic density to be equal to the dark matter density Main annihilation channels to Light fermion-antifermion for small masses W-W production for large masses

23 Only a small window might have been ruled out by CDMS and Xenon

24 Indirect Detection Belotsky, Khlopov, CK Muon flux limits from Super-Kamiokande exclude the area from 100 to 200 GeV.

25 Indirect Detection II Can self annihilation change the cooling curves of a neutron star? Main processes: neutrinos emission URCA Photon emission from the surface CK arxiv: CK,Tinyakov arxiv:

26 3. Strongly interacting particles 3. Te Khlopov, CK If UU or ζ are the lightest particles of the TC sector Bound states or/and For a technibaryon of mass ~TeV, the binding energy is ~1.6 MeV

27 Conclusions Technicolor theories are not ruled out by the electroweak measurements. They don t have many of the old problems. They are simple and can be tested at LHC. Technicolor models can provide different dark matter candidates spanning all possibilities, one similar to neutralino and one of SIMP type. Possible explanation of PAMELA results! DAMA data? The dark matter candidates are not ruled out by any observations or direct search dark matter experiments.