Moduli -Induced Axion Problem

1. 2013 Oct.24th@Tohoku Moduli-Induced Axion Problem TetsutaroHigaki (KEK) 1208.3563 and 1304.7987 with K. Nakayamaand F. Takahashi

2. 2013 Oct.24th@Tohoku Moduli-Induced AxionProbefor extra dimensions TetsutaroHigaki (KEK) 1208.3563 and 1304.7987 with K. Nakayamaand F. Takahashi

3. Cosmological test for stringmodels CMB Ex-dim.+ D-branes Axionic dark radiation(= relativistic DM): ΔNeff = O(0.1)

4. Key: Moduli problem in reheating Φ: Moduli/Inflatona: Axion Axionic dark radiation exists even for mΦ >> 100TeV.

5. Dark radiation

6. Dark radiation ΔNeffin ρrad ΔNeff:Dark radiation, Neff: Effective neutrino number, 3.046: The SM value

7. Effective neutrino number Neff • Observations from Planck (95%): [Planck collaborations] (CMB) (CMB+BAO) (CMB+H0)

8. Effective neutrino number Neff • Observations from Planck (95%): Dark radiation is hinted, while tension between H0 measurement and CMB/BAO. See also [Hamann and Hasenkamp]: (CMB+HST+C+BAO+WL) [Planck collaborations] (CMB) (CMB+BAO) (CMB+H0)

9. Axions in string theory: Dark radiation candidates

10. QCD axion: Strong CP and CDM Ultralight . Original motivations: • A solution of strong CP problem: θ < 10-10 • A candidate of CDM

11. Gravity Motivation for string theory Unified theory including quantum gravity! Matter Gauge D-brane

12. Axions in string theory • Axions via compactifications: They can be ultralightand very weak • shift symmetry:aaaaaaaaaaaa; • solution of CP and/or CDMwith Cn: n-form gauge field for strings/branes.

13. Moduli Reheating field: • String moduli: Long lifetime: Light + 1/MPl (if SUSY) • Other possibilities: • Inflaton (also in non-SUSY if coupled toaxions) • Open string state, e.g., SUSY-breaking fields

14. Moduli oscillation [Coughlan et al.] : moduli VEV : Inflaton potential The decay = Reheating + dark radiation. Radiation Radiation Radiation Vinflation Vinflation Vinflation Vmoduli Vmoduli Vmoduli

15. Moduli problems • Non-SUSY moduli: mΦ≦ m3/2 + light axion Moduli-Induced Axion problem: • SUSY moduli: mΦ > m3/2 Moduli-induced gravitino problem: [Cicoli, Conlon, Quevedo], [TH, Takahashi], [TH, Nakayama, Takahashi]. [Endo, Hamaguchi, Takahashi], [Nakamura, Yamaguchi]

16. Moduli-Induced Axion Problem;moduli decay modesWe will use 4D N=1 SUGRA.(MPl = 1)

17. Axion production via the kinetic term Moduli-axions coupling exists in general! Φ: Moduli;K: invariant under δT = iα:

18. The decay fractions of Φ

19. The decay fractions of Φ

20. The decay fractions of Φ

21. The decay fractions of Φ

22. The decay fractions of Φ ∵ 　　　 after moduli decay

23. Constraint on decay widths of Φ [TH, Nakayama, Takahashi] TR ΔNeff >0.84 ruled out: Br(Φ→2a) > O(0.1) or TR < O(1) MeV

24. Two examples:The problem and solution

25. 1. No-scale a la Large Volume Scenario [Balasubramanian, Berglund, Conlon, Quevedo] Φ = Re(T) : Volume modulus; a = Im(T): Axion. The SM Swiss-cheese Calabi-Yau

26. 1. No-scale a la Large Volume Scenario [Blumenhagen, Conlon, Krippendorf, Moster, Quevedo] 1/T3/2; T fixed. Φ = Re(T) : Volume modulus; a = Im(T): Axion.

27. 1. No-scale a la Large Volume Scenario [Blumenhagen, Conlon, Krippendorf, Moster, Quevedo] Φ = Re(T) : Volume modulus; a = Im(T): Axion.

28. 1. No-scale a la Large Volume Scenario Φ = Re(T) : Volume modulus; a = Im(T): Axion.

29. ΔNeff in (mΦ, z) [TH, Takahashi] ΔNeff～ 0.2: z ～3 or Many Higgses (MSSM extension)

30. Mass and momentum • ma～ e-2πT～ 10-100000eV , • Decoupled from the SM: fa≧MPl • Pa～0.1 -1 keV (today)

31. Implication in string theory? ΔNeff～ 0.2 Hd z～3: Strong bulk-brane coupling. (z =1 for a Gauge-Higgs Unification) Hu Many intersections (~ 6-9) among D-branes?

32. 2. Ex-dim with two holes [Choi, Jeong] Calabi-Yau T1 T2 T0 The SM (D7) NP (D7/E3) on T1 + nT2 NP on the bulk

33. 2. Ex-dim with two holes [Choi, Jeong] Calabi-Yau T1 T2 T0 The SM (D7) NP (D7/E3) on T1 + nT2 NP on the bulk

34. 2. Ex-dim with two holes: Stabilization [Choi, Jeong] ・

35. 2. Ex-dim with two holes: Stabilization [Choi, Jeong] ・ ・

36. 2. Ex-dim with two holes: Stabilization [Choi, Jeong] ・ ・ ・

37. 2. Ex-dim with two holes: Decay [TH, Nakayama, Takahashi] • Saxion-decay into QCD axions; can be suppressed! ;

38. 2. Ex-dim with two holes: Decay [TH, Nakayama, Takahashi] • Saxion-decay into QCD axions; can be suppressed! (Ba > 0.12 for TR ~0.1GeV ) ; Ng = 12 for the MSSM.

39. Mass and momentum if exists • ma～ 10-10eV , • fa～ MGUT～1016GeV. • Pa～0.1 -1 keV (today)

40. 2. Ex-dim with two holes: Decay [TH, Nakayama, Takahashi] • Saxion-decay into QCD axions; can be suppressed! (Ba > 0.12 for TR ~0.1GeV ) ; Ng = 12 for the MSSM.

41. Symmetric Ex-dim: T1⇔ T2 ΔNeff <0.1 Calabi-Yau T1 T2 T0

42. Conclusion

43. Cosmological test for stringmodels CMB Ex-dim.+ D-branes Axionic dark radiation(= relativistic DM): ΔNeff = O(0.1)

44. Key: Moduli problem in reheating Φ: Moduli/Inflatona: Axion Axionic dark radiation exists even for mΦ >> 100TeV.

45. Discussions on axion mass Shift symmetry or U(1)PQcan be broken (to ZN) by • Flux compactifications/torsional geometry • Stringy instantons(NOT QCD) • Light axion might appear, e.g., when Adjoint states: S: 4-cycle on CY or Many chiralstates: D: Dirac operator on a D-brane.

46. Thank you!

47. Backup

48. Constraint on axion dark radiation 1306.6518 [TH, Nakayama, Takahashi] • Axion-photon conversion in the early universe Dark radiation = (Non-)QCD axion with large p Primordial