Pangenesis in a Baryon-Symmetric Universe: Dark and Visible Matter via the Affleck-Dine Mechanism

Transcription

1 Pangenesis in a Baryon-Symmetric Universe: Dark and Visible Matter via the Affleck-Dine Mechanism Kalliopi Petraki University of Melbourne (in collaboration with: R. Volkas, N. Bell, I. Shoemaker) COSMO 2011, Porto Portugal

2 The Content of our Universe Understanding the relic abundance of all components requires physics beyond the Standard Model.

3 The Visible Matter Stability: conserved baryon number at low energies Relic abundance : asymmetry To make this we need processes which (i) violate at high energies (ii) violate (iii) occur out of thermal equilibrium depends on

4 The Dark Matter Relic abundance: Not too hot: Hints of direct detection from DAMA, CoGeNT: many candidates, different parameters.

5 The Dark Matter One approach Identify a DM candidate within well-motivated extensions of the SM from particle physics, e.g. Hierarchy problem Strong CP problem Neutrino masses Another approach Rely on what we observe about DM itself : and possibly Data may tell us more than just fit model parameters Cosmic coincidence LSP, axion, sterile neutrinos

6 Cosmic Coincidence Why? production mechanisms unrelated relevant parameters different relic abundances expected to vary greatly. Related production mechanisms?

7 Strategy Take coincidence seriously: generate dark and visible matter simultaneously Seek how this can be explained within well-motivated extensions of the SM Pangenesis in supersymmetric models via the Affleck-Dine mechanism [Bell, KP, Shoemaker, Volkas (2011)]

8 Symmetry Structure Stabilizing symmetries at low energies Visible sector : Dark sector : Diagonal symmetries or Symmetry breaking : always unbroken : broken at high energies, restored at low energies high energies

9 Cosmological evolution high energies Early Universe explicit violation generate, while Separation of baryonic antibaryonic charge in visible and dark sectors [Dodelson, Widrow (1990)]. Late Universe and conserved separately to ensure stability of the sectors; asymmetries of the two sectors related.

10 Separation of baryonic antibaryonic charge Generation of asymmetry: standard baryogenesis techniques in models with extended particle content: Decays [Kitano, Low (2006); Davoudiasl et al. (2010)] Asymmetric freeze-out [Farrar, Zaharijas (2004)] Affleck-Dine [Bell, KP, Shoemaker, Volkas (2011)] Others... Each mechanism is operative for different BSM physics and different cosmology.

11 a note on asymmetric DM scenarios Models with an unbroken symmetry (baryon-symmetric) Baryon antibaryon separation: simultaneous DM and VM genesis Possible gauge symmetry pheno in colliders [Dodelson, Widrow (1990); Farrar, Zaharijas (2004); Kitano, Low (2006); Davoudiasl et al. (2010); Bell et al. (2011)] Models with no unbroken symmetry Baryogenesis in either sector independently Sharing of the asymmetry via chemical equilibrium [Nussinov (1985); ; Kaplan, Luty, Zurek (2009);...]

12 The Affleck-Dine Mechanism for generation of an asymmetry Coherent production of a charge from oscillations of a scalar condensate. Ingredients (toy version): Complex scalar field carrying a charge Small & violating terms in the scalar potential complex Large initial field vev

13 Dynamics The Affleck-Dine Mechanism for generation of an asymmetry Initial conditions Oscillations of around the minimum. terms generate a time-dependent complex phase for small, so that charge conserved at low energies (small vevs) effect of quartic terms amplified by large field vev

14 Questions The Affleck-Dine Mechanism and particle-physics models What is the identity of the scalar fields which carry baryon/lepton number? How do they acquire large vevs in the early universe? Why are the B or L violating quartic terms so small? How is the B or L asymmetry transferred to ordinary particles? Answers Supersymmetry

15 The Affleck-Dine Mechanism in supersymmetric models Identity of the scalar fields carrying B or L? squarks, sleptons, and other scalars in extensions of MSSM. Large vevs in the early universe? scalar potential of susy theories has flat directions with vanishing quartic terms, at the renormalizable level. Smallness of B or L violating quartic terms? non-renormalizable interactions along flat directions. Asymmetry transfer into ordinary particles? decay of the scalars, in a B & L preserving way.

16 Pangenesis high energies Pangenesis occurs along flat directions with warranted along flat directions if gauged. Unbroken makes it natural that it be a gauge symmetry.

17 A simple model of Pangenesis Introduce three SM gauge singlet chiral superfields and vector-like partners Baryo/leptonic charge assignments: At the renormalizable level, impose symmetries:

18 A simple model of Pangenesis are flat directions (no quartic terms). Flat directions lifted by non-renormalizable susy and susybreaking operators. -violating interactions included with j = 0,1,2 and k =0,1,2,3. The Affleck-Dine mechanism operates along the flat manifold, generating an asymmetry. The connector fields decay into purely visible and purely dark sector fields, via renorm couplings, preserving Baryonic antibaryonic charge separated.

19 A simple model of Pangenesis Scalar potential along flat directions where Hubble parameter (potential includes: susy non-renormalizable terms; susy-breaking by hidden sector & vacuum energy; thermal corrections)

20 A simple model of Pangenesis Scalar potential along flat directions large field vev after inflation where Hubble parameter (potential includes: susy non-renormalizable terms; susy-breaking by hidden sector & vacuum energy; thermal corrections)

21 A simple model of Pangenesis Scalar potential along flat directions large field vev after inflation where Hubble parameter (potential includes: susy non-renormalizable terms; susy-breaking by hidden sector & vacuum energy; thermal corrections)

22 A simple model of Pangenesis Scalar potential along flat directions large field vev after inflation where Hubble parameter (potential includes: susy non-renormalizable terms; susy-breaking by hidden sector & vacuum energy; thermal corrections)

23 A simple model of Pangenesis X asymmetry generated Asymmetry generation suppressed by thermal effects, but enhanced by multiple flat directions. (δ: effective CP-violating phase, λ: Yukawa couplings of non-renormalizable terms in the superpotential) Visible and Dark sector asymmetries related

24 A simple model of Pangenesis Asymmetry cascade, via preserving operators unlimited possibilities Lightest charged particles

25 Pangenesis Details of the Dark Sector: Annihilation of the symmetric part of dark matter into dark-sector radiation: dark U(1) force, w/ possible kinetic mixing to hypercharge. Prediction of the dark-matter mass (already favoured by DAMA, CoGeNT) Dark-matter direct detection: via

26 Other models of Pangenesis Flat direction fields uncharged under generalised B-L Generalised B-L spontaneously broken along flat directions

27 a note on recent literature Pangenesis or Cogenesis arxiv: [Bell, KP, Shoemaker, Volkas] arxiv: [Cheung, Zurek] Same symmetry structure and asymmetry generation mechanism. Different illustrations of the mechanism.

28 Conclusions Similarity of visible and dark matter abundances hints towards a common origin. This can be explained in a universe with a generalised and unbroken global The separation of baryonic antibaryonic charge can happen via the Affleck-Dine mechanism in extensions of MSSM. Evidence of pangenesis: Supersymmetry, ~ 10 GeV DM, a gauged B-L with invisible decay width not accounted by neutrinos, and a dark U(1) force with kinetic mixing.